INI CET cheat sheet

Brachial plexus roots: C5–T1; Erb palsy (C5–C6) gives waiter's tip, Klumpke (C8–T1) gives claw hand with Horner syndrome.

Coronary arteries arise from aortic sinuses; left main divides into LAD (supplies anterior two-thirds of septum) and circumflex.

Cerebral blood supply: anterior circulation via internal carotid; posterior via vertebrobasilar; circle of Willis links them at the base.

GFR = Kf × net filtration pressure; normal GFR ~125 mL/min; filtration fraction = GFR/renal plasma flow (~0.2).

Oxygen–haemoglobin curve shifts right (↓affinity) with ↑CO2, ↑H+, ↑temperature, ↑2,3-BPG; fetal Hb shifts left.

Cardiac output = heart rate × stroke volume; Fick principle: CO = O2 consumption / arteriovenous O2 difference.

Rate-limiting enzymes: glycolysis phosphofructokinase-1; gluconeogenesis fructose-1,6-bisphosphatase; TCA isocitrate dehydrogenase; cholesterol HMG-CoA reductase.

Urea cycle: carbamoyl phosphate synthetase I is mitochondrial and rate-limiting; arginase deficiency causes hyperargininaemia.

Resting membrane potential depends mainly on K+ permeability; Na+/K+ ATPase pumps 3 Na+ out and 2 K+ in per ATP.

Cell injury: reversible shows swelling and blebs; irreversible shows mitochondrial membrane rupture and membrane integrity loss; apoptosis is caspase-dependent and non-inflammatory.

Virchow's triad: endothelial injury, stasis/turbulence, hypercoagulability - the framework for thrombosis risk.

Tumour suppressor genes: RB (retinoblastoma), TP53 (Li-Fraumeni), APC (FAP), BRCA1/2 (breast-ovarian); oncogenes include RAS, MYC, HER2.

Pharmacokinetics: zero-order elimination = constant amount per time (phenytoin, ethanol, aspirin at high dose); first-order = constant fraction.

Hepatic enzyme inducers: rifampicin, phenytoin, carbamazepine, phenobarbitone, rifabutin; inhibitors: ketoconazole, erythromycin, cimetidine, ritonavir.

Organisms: Gram-positive cocci in clusters = Staphylococcus; in chains = Streptococcus; lancet-shaped diplococci = Streptococcus pneumoniae.

Sterilisation: autoclave 121°C at 15 psi for 15–20 min; hot air oven 160°C for 2 h; ethylene oxide for heat-labile items.

Rigor mortis appears 1–2 h after death, full in 12 h, resolves by 24–48 h; livor mortis fixes by 6–8 h.

Sensitivity = TP/(TP+FN); specificity = TN/(TN+FP); positive predictive value depends on prevalence.

Acute MI: ST elevation in contiguous leads, troponin rise at 3–6 h, peak 12–24 h; aspirin plus primary PCI if within 12 h of symptom onset.

DKA: glucose >250 mg/dL, pH <7.3, bicarbonate <18 mEq/L, ketonaemia; treat with isotonic saline, insulin infusion, potassium replacement.

Cirrhosis complications: portal hypertension → varices, ascites, splenomegaly; spontaneous bacterial peritonitis diagnosed by ascitic PMN >250/mm³.

Acute pancreatitis diagnosis needs 2 of 3: characteristic pain, lipase/amylase >3× upper limit, or imaging findings.

Obstetric haemorrhage: antepartum causes are placenta praevia, abruption, vasa praevia; postpartum atony is the commonest cause of PPH.

Preeclampsia: BP ≥140/90 after 20 weeks plus proteinuria or end-organ dysfunction; magnesium sulphate prevents and treats eclampsia.

Paediatric milestones: social smile 6 weeks, head holding 3 months, sitting without support 6 months, walking 12–15 months.

Neonatal jaundice: physiological appears after 24 h, peaks day 3–5; jaundice within 24 h is always pathological.

Thyroid: primary hypothyroidism shows high TSH with low free T4; subclinical shows high TSH with normal free T4.

Cranial nerves: III, IV, VI, XI, XII are motor; I, II, VIII are sensory; V, VII, IX, X are mixed.

Lung segments: right lung has 10 segments in 3 lobes; left has 8–10 in 2 lobes; lingula is the left counterpart of the middle lobe.

Insulin lowers blood glucose by promoting GLUT4 translocation in muscle and adipose; glucagon raises it via glycogenolysis and gluconeogenesis.

Respiratory quotient: carbohydrate 1.0, protein 0.8, fat 0.7; measured by indirect calorimetry.

Enzyme kinetics: Km is substrate concentration at half Vmax; competitive inhibitors raise Km without changing Vmax.

Vitamin deficiencies: thiamine (beriberi, Wernicke), riboflavin (angular stomatitis), niacin (pellagra), pyridoxine (peripheral neuropathy), cobalamin (subacute combined degeneration).

Cardiac cycle: S1 from mitral and tricuspid closure; S2 from aortic and pulmonary closure; S3 in early diastole; S4 from atrial contraction.

Renal tubule: proximal convoluted tubule reabsorbs ~65% of filtered Na+ and water; thick ascending limb is impermeable to water (diluting segment).

Thyroid hormone synthesis requires iodine uptake by NIS, oxidation by thyroid peroxidase, and coupling of MIT/DIT to T3/T4.

Hypersensitivity types: I IgE (anaphylaxis), II antibody-mediated (haemolysis), III immune complex (SLE, PSGN), IV T-cell mediated (TB, contact dermatitis).

Necrosis types: coagulative (ischaemia except brain), liquefactive (brain, abscess), caseous (TB), fat (pancreatitis), fibrinoid (vasculitis).

Antibiotic mechanisms: β-lactams inhibit cell wall synthesis; aminoglycosides bind 30S; macrolides bind 50S; fluoroquinolones inhibit DNA gyrase.

Antitubercular drugs: isoniazid causes peripheral neuropathy (give pyridoxine) and hepatitis; rifampicin causes orange urine and induces CYP450.

Vaccines: BCG at birth; OPV zero dose at birth; DPT at 6, 10, 14 weeks; measles-rubella at 9–12 months and 16–24 months.

Infection control: standard precautions apply to all patients; N95 respirator for airborne (TB, measles); surgical mask for droplet.

Medicolegal: age of consent for examination in India is 18 years; Section 375 IPC defines rape; POCSO covers children under 18.

Screening tests: lead-time bias inflates apparent survival; length bias favours detection of slow-growing disease.

Biostatistics: sensitivity and specificity are prevalence-independent; PPV and NPV vary with prevalence.

Stroke: thrombolysis with alteplase within 4.5 h of onset if no contraindication; CT excludes haemorrhage before treatment.

Hypertension: stage 1 ≥140/90, stage 2 ≥160/100; first-line agents include ACE inhibitors, ARBs, calcium channel blockers, thiazides.

Fracture healing stages: haematoma, fibrocartilaginous callus, bony callus, remodelling; union typically 6–12 weeks depending on site.

Appendicitis: migration of pain to right iliac fossa, McBurney point tenderness, Alvarado score ≥7 suggests operative management.

Labour stages: first to full dilatation, second to delivery of baby, third to delivery of placenta; active first stage is ≥4 cm with regular contractions.

Gestational diabetes screening: 75 g OGTT at 24–28 weeks; fasting ≥92, 1 h ≥180, 2 h ≥153 mg/dL (IADPSG criteria).

Paediatric dehydration: WHO ORS has 75 mEq/L sodium for rehydration and 45 mEq/L for maintenance; zinc for 14 days in diarrhoea.

Anaphylaxis: intramuscular adrenaline 0.01 mg/kg (max 0.5 mg) of 1:1000 into the anterolateral thigh, repeat every 5–15 min.

Diabetes: HbA1c reflects 8–12 weeks of glycaemia; diagnosis at ≥6.5% (48 mmol/mol) on a standardised assay.

Heart sounds and murmurs: mitral stenosis gives mid-diastolic rumble with opening snap; aortic stenosis gives ejection systolic murmur radiating to carotids.

Muscle contraction: actin–myosin crossbridge cycling requires Ca2+ binding to troponin C; ATP hydrolysis drives the power stroke.

Gut hormones: gastrin from G cells, secretin from S cells, CCK from I cells, GIP from K cells; each responds to specific luminal nutrients.

Lipid transport: chylomicrons carry dietary fat; VLDL carries endogenous triglyceride; LDL delivers cholesterol; HDL performs reverse cholesterol transport.

DNA replication: leading strand synthesised continuously, lagging strand in Okazaki fragments; DNA polymerase reads 3'→5' and synthesises 5'→3'.

Genetic disorders: Down syndrome trisomy 21; Turner 45,X; Klinefelter 47,XXY; Edwards trisomy 18; Patau trisomy 13.

Acid–base: respiratory acidosis shows low pH with high PaCO2; metabolic acidosis shows low pH with low bicarbonate and compensatory hyperventilation.

Action potential: depolarisation by Na+ influx, repolarisation by K+ efflux, hyperpolarisation from slow K+ channels; refractory period prevents tetany in cardiac muscle.

Inflammation: acute mediators include histamine, bradykinin, prostaglandins, leukotrienes; chronic inflammation features macrophages and lymphocytes.

Anaemia classification: microcytic (iron deficiency, thalassaemia), normocytic (chronic disease, haemolysis), macrocytic (B12, folate, alcohol).

Anticoagulants: heparin acts via antithrombin III (monitor aPTT); warfarin inhibits vitamin K epoxide reductase (monitor INR); DOACs inhibit factor Xa or thrombin.

Antihypertensives in pregnancy: labetalol, nifedipine, methyldopa are safe; ACE inhibitors and ARBs are contraindicated.

Culture media: MacConkey for Gram-negative bacilli, blood agar for fastidious organisms, Löwenstein-Jensen for Mycobacterium tuberculosis.

Notifiable diseases in India include cholera, plague, yellow fever, dengue, polio; immediate notification required for outbreak control.

Asphyxial deaths: petechial haemorrhages, cyanosis, congestion; hanging shows a ligature mark above the thyroid cartilage.

Relative risk and odds ratio: RR used in cohort studies, OR in case–control; OR approximates RR when disease is rare.

Heart failure: reduced ejection fraction ≤40%; treat with ACE inhibitor/ARNI, beta-blocker, mineralocorticoid antagonist, SGLT2 inhibitor.

COPD: post-bronchodilator FEV1/FVC <0.70 confirms airflow obstruction; GOLD stages use FEV1 percentage predicted.

Thyroid surgery: recurrent laryngeal nerve injury causes hoarseness; external branch of superior laryngeal nerve injury affects high pitch.

Breast cancer: staging uses TNM; sentinel node biopsy for clinically node-negative axilla; triple-negative lacks ER, PR, HER2.

Menopause: diagnosis clinical after 12 months amenorrhoea; FSH >30 IU/L supports diagnosis; hormone therapy for vasomotor symptoms.

Paediatric growth: weight doubles by 5 months, triples by 1 year; birth length ~50 cm, adult height predicted from mid-parental formula.

Neonatal resuscitation: warm, dry, stimulate; positive pressure ventilation if apnoeic or heart rate <100/min; chest compressions if heart rate <60/min.

Fever in children: antipyretics are paracetamol 15 mg/kg/dose or ibuprofen 10 mg/kg/dose; avoid aspirin due to Reye syndrome.

Autonomic nervous system: sympathetic preganglionic fibres are short and release acetylcholine; postganglionic release noradrenaline (except sweat glands, which use acetylcholine).

Limbic system: hippocampus consolidates memory; amygdala mediates fear; hypothalamus regulates temperature, hunger, and circadian rhythm.

Bone remodelling: osteoclasts resorb bone, osteoblasts form bone; PTH increases resorption, calcitonin inhibits it, vitamin D increases calcium absorption.

Glycogen storage diseases: von Gierke (glucose-6-phosphatase), Pompe (lysosomal acid maltase), McArdle (muscle phosphorylase), Cori (debranching enzyme).

Electrolyte disturbances: hyperkalaemia shows tall peaked T waves; hypokalaemia shows flattened T waves and U waves.

Thyroid function tests: total T4 affected by binding proteins; free T4 and TSH are the preferred initial tests.

Nerve conduction: A-alpha fibres are fastest and myelinated; C fibres are slow, unmyelinated, and carry pain and temperature.

Body fluid compartments: total body water ~60% of body weight; intracellular ~40%, extracellular ~20% (interstitial 15%, plasma 5%).

Glasgow Coma Scale: eye 4, verbal 5, motor 6; total 3–15; score ≤8 indicates need for airway protection.

Poisoning: organophosphate causes SLUDGE and miosis; treat with atropine and pralidoxime; opioid overdose responds to naloxone.

Tumour markers: AFP (hepatocellular carcinoma, yolk sac), CEA (colorectal), CA-125 (ovarian), PSA (prostate), hCG (trophoblastic).

Antibiotic resistance mechanisms: β-lactamase production, efflux pumps, altered penicillin-binding proteins, ribosomal methylation.

Sensitivity testing: disc diffusion (Kirby–Bauer) interpreted by zone diameter; MIC determined by broth dilution or E-test.

Community medicine: incidence measures new cases; prevalence measures existing cases; both expressed per 1,000 or 100,000 population.

Epidemiological study designs: cohort gives incidence and relative risk; case–control is cheaper and suited to rare diseases.

Vitreous humour and cerebrospinal fluid are useful for postmortem biochemistry, including glucose and electrolyte estimation.

Cirrhosis: Child–Pugh score uses bilirubin, albumin, INR, ascites, encephalopathy; MELD uses bilirubin, INR, creatinine.

Chronic kidney disease: eGFR <60 for ≥3 months; stage 5 is <15; treat with blood pressure control, ACE inhibitor/ARB, and SGLT2 inhibitor.

Sepsis: qSOFA uses respiratory rate ≥22, altered mentation, systolic BP ≤100; sepsis-3 defines organ dysfunction by SOFA score.

Trauma: ATLS primary survey is airway with cervical spine protection, breathing, circulation, disability, exposure; FAST detects free intraperitoneal fluid.

Obstetric ultrasound: gestational sac visible at 4–5 weeks, fetal pole at 6 weeks, cardiac activity at 6–7 weeks.

Contraception: combined oral pills contraindicated in migraine with aura, smoking over 35, and history of venous thromboembolism.

Immunisation: live vaccines (MMR, varicella, oral polio) are contraindicated in immunocompromised patients and pregnancy.

Otitis media: common organisms are Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis; first-line amoxicillin.

Lung volumes: tidal volume ~500 mL; vital capacity = inspiratory reserve + tidal + expiratory reserve; residual volume cannot be measured by spirometry.

Cardiac output distribution: kidneys receive ~20% of cardiac output, liver ~25%, brain ~15%, coronary circulation ~5%.

Haemoglobin: adult HbA is α2β2; HbF is α2γ2 with higher oxygen affinity; HbA2 is α2δ2.

Protein structure: primary is amino acid sequence; secondary is α-helix and β-sheet; tertiary is 3D folding; quaternary is multiple subunits.

Vitamins: fat-soluble vitamins A, D, E, K are stored in liver; water-soluble vitamins are excreted and require regular intake.

Cellular respiration: glycolysis yields 2 ATP and 2 NADH; TCA cycle yields 3 NADH, 1 FADH2, 1 GTP per acetyl-CoA.

Renal clearance: clearance = (urine concentration × urine flow) / plasma concentration; inulin clearance measures GFR.

Thermoregulation: hypothalamus anterior centre dissipates heat; posterior centre conserves heat; shivering is mediated by posterior hypothalamus.

Apoptosis pathways: intrinsic via mitochondria and cytochrome c; extrinsic via death receptors such as Fas; both activate caspases.

Shock types: hypovolaemic, cardiogenic, distributive (septic, anaphylactic), obstructive; septic shock is characterised by vasodilation and warm skin.

Pharmacology of diabetes: metformin reduces hepatic gluconeogenesis; sulfonylureas stimulate insulin release; SGLT2 inhibitors cause glycosuria.

Antimalarials: chloroquine for sensitive Plasmodium vivax; artemisinin-based combination therapy for falciparum; primaquine for hypnozoites after G6PD testing.

Sterilisation monitoring: physical (autoclave tape), chemical (Bowie–Dick), biological (Geobacillus stearothermophilus spores).

Forensic entomology: blowfly eggs appear within hours; larval stages estimate postmortem interval in warm climates.

Community medicine: herd immunity threshold depends on basic reproduction number; measles needs very high coverage (~95%).

Biostatistics: type I error is false positive, type II error is false negative; power = 1 − type II error.

Asthma: reversible airflow obstruction, FEV1 improves ≥12% and 200 mL after bronchodilator; inhaled corticosteroid is controller therapy.

Pneumonia: CURB-65 uses confusion, urea >7 mmol/L, respiratory rate ≥30, BP <90/60, age ≥65; score ≥2 suggests admission.

Hernia: indirect inguinal passes through deep ring lateral to inferior epigastric vessels; direct passes through Hesselbach triangle medial to them.

Burns: Parkland formula gives 4 mL/kg/% burn of Ringer lactate in 24 h; half in first 8 h from injury.

Pregnancy: estimated date of delivery by Naegele rule - first day of last menstrual period plus 7 days minus 3 months.

Ectopic pregnancy: risk factors include previous ectopic, tubal surgery, pelvic inflammatory disease; diagnose with transvaginal ultrasound and hCG.

Paediatric asthma: inhaled corticosteroid plus short-acting beta-2 agonist as reliever; spacer improves delivery in young children.

Osteoporosis: T-score ≤ −2.5 on DXA; treat with bisphosphonates, calcium, vitamin D, and weight-bearing exercise.

Spinal cord tracts: dorsal columns carry vibration and proprioception; spinothalamic carries pain and temperature; corticospinal carries motor.

Cerebellum: midline vermis controls axial posture; lateral hemispheres control limb coordination; lesions cause intention tremor and ataxia.

Pituitary: anterior lobe secretes GH, TSH, ACTH, FSH, LH, prolactin; posterior lobe stores ADH and oxytocin.

Membrane transport: simple diffusion, facilitated diffusion (GLUT), primary active transport (Na+/K+ ATPase), secondary active transport (SGLT).

Hormone action: steroid hormones enter cells and act on nuclear receptors; peptide hormones act via surface receptors and second messengers.

Metabolic pathways: HMP shunt generates NADPH and ribose-5-phosphate; deficiency of G6PD causes haemolysis after oxidative stress.

Blood coagulation: intrinsic pathway uses factors VIII, IX, XI, XII; extrinsic uses tissue factor and VII; both converge at factor X.

Amino acid metabolism: phenylalanine hydroxylase deficiency causes phenylketonuria; homocystinuria from cystathionine beta-synthase deficiency.

Autoimmune diseases: SLE shows anti-dsDNA and anti-Sm; rheumatoid arthritis shows anti-CCP; Sjögren shows anti-Ro/La.

Renal pathology: nephrotic syndrome shows heavy proteinuria >3.5 g/day, hypoalbuminaemia, oedema, hyperlipidaemia; minimal change is commonest in children.

Antiepileptic drugs: sodium valproate causes hepatotoxicity and teratogenicity; phenytoin causes gingival hyperplasia and hirsutism.

Antiviral therapy: HIV uses combination antiretroviral therapy; hepatitis B treated with tenofovir or entecavir; hepatitis C with direct-acting antivirals.

Bacterial toxins: diphtheria toxin inhibits protein synthesis via ADP-ribosylation of EF-2; cholera toxin increases cAMP.

Drowning: freshwater causes haemodilution and hyperkalaemia; saltwater causes haemoconcentration and pulmonary oedema.

Community medicine: infant mortality rate = infant deaths under 1 year per 1,000 live births in the same year.

Screening: Wilson–Jungner criteria include important disease, accepted treatment, suitable test, and cost-effectiveness.

Arrhythmias: atrial fibrillation shows irregularly irregular rhythm with absent P waves; rate control with beta-blocker or calcium channel blocker.

Valvular disease: mitral regurgitation gives pansystolic murmur at apex radiating to axilla; aortic regurgitation gives early diastolic murmur.

Intestinal obstruction: features are colicky pain, vomiting, distension, absolute constipation; erect abdominal X-ray shows air–fluid levels.

Uterine fibroids: commonest benign pelvic tumour; menorrhagia and pressure symptoms; treatment options include myomectomy and hysterectomy.

Polycystic ovary syndrome: Rotterdam criteria require two of oligo/anovulation, hyperandrogenism, and polycystic ovaries on ultrasound.

Paediatric pneumonia: tachypnoea is the most sensitive sign; WHO thresholds are ≥60/min under 2 months, ≥50/min for 2–12 months, ≥40/min for 1–5 years.

Diabetic foot: assess pulses, sensation, and infection; offloading and debridement are essential; avoid tight dressings.

Meningitis: lumbar puncture after CT if focal signs, seizures, or immunocompromise; empirical ceftriaxone plus vancomycin for adults.

Skull foramina: foramen ovale transmits mandibular nerve; foramen rotundum maxillary nerve; foramen spinosum middle meningeal artery.

Cardiac conduction: SA node is the pacemaker, AV node delays conduction, bundle of His and Purkinje fibres distribute impulses to ventricles.

Pulmonary circulation: low pressure and low resistance; hypoxia causes hypoxic pulmonary vasoconstriction, unlike systemic circulation.

Enzyme regulation: allosteric modulation, covalent modification (phosphorylation), and induction/repression of gene expression.

Nucleotide metabolism: purines synthesised de novo from PRPP; salvage via HGPRT; deficiency causes Lesch–Nyhan syndrome.

Gastrointestinal secretion: parietal cells secrete HCl via H+/K+ ATPase; intrinsic factor is required for vitamin B12 absorption.

Skeletal muscle types: type I fibres are slow, oxidative, fatigue-resistant; type II fibres are fast, glycolytic, fatiguable.

Fetal circulation: ductus arteriosus shunts pulmonary artery to aorta; foramen ovale shunts right to left atrium; ductus venosus bypasses liver.

Amyloidosis: Congo red stain shows apple-green birefringence under polarised light; types include AL, AA, and Aβ.

Granulomas: caseating in tuberculosis; non-caseating in sarcoidosis and Crohn disease; foreign-body type around sutures.

Drug interactions: warfarin potentiated by amiodarone, metronidazole, and fluconazole; antagonised by rifampicin.

Immunisation schedule: hepatitis B birth dose within 24 h; rotavirus at 6, 10, 14 weeks; pneumococcal conjugate in infancy.

Microscopy: Ziehl–Neelsen stain for acid-fast bacilli; Gram stain differentiates Gram-positive (purple) and Gram-negative (pink).

Postmortem changes: algor mortis (cooling), livor mortis (lividity), rigor mortis (stiffening), putrefaction; each has a characteristic timeline.

Community medicine: crude birth rate = live births per 1,000 population per year; crude death rate = deaths per 1,000 population per year.

Randomised controlled trial: randomisation reduces selection bias; blinding reduces measurement bias; intention-to-treat analysis preserves randomisation.

Tuberculosis: sputum smear and GeneXpert for diagnosis; regimen is 2 months intensive with HRZE followed by 4 months continuation with HRE.

Malaria: falciparum shows ring forms and banana-shaped gametocytes; severe malaria treated with intravenous artesunate.

Dengue: warning signs include abdominal pain, persistent vomiting, fluid accumulation, bleeding, lethargy; monitor haematocrit and platelets.

Thyroid nodules: fine-needle aspiration cytology is first-line; Bethesda categories guide surgery; papillary carcinoma spreads via lymphatics.

Colorectal cancer: right-sided lesions cause anaemia; left-sided cause obstruction; screen with colonoscopy or faecal occult blood.

Pre-eclampsia: severe features include BP ≥160/110, platelets <100,000, liver enzymes elevated, renal insufficiency, pulmonary oedema.

Neonatal sepsis: early-onset within 72 h from maternal flora; late-onset from environment; empirical ampicillin plus gentamicin.

Rheumatic fever: Jones criteria include carditis, arthritis, chorea, erythema marginatum, subcutaneous nodules; treat with penicillin.

Joint types: synovial joints have a cavity and hyaline cartilage; symphyses are cartilaginous; sutures are fibrous.

Nerve injuries: neurapraxia is reversible conduction block; axonotmesis preserves the sheath; neurotmesis requires surgical repair.

Hormonal feedback: negative feedback maintains thyroid and adrenal hormones; positive feedback occurs in ovulation and labour.

Protein digestion: pepsin in stomach, pancreatic trypsin and chymotrypsin in duodenum; absorbed as amino acids and dipeptides.

Cholesterol synthesis: HMG-CoA reductase is rate-limiting; statins inhibit it; bile acids are the major excretion route.

Acid–base compensation: respiratory compensation for metabolic acidosis is rapid hyperventilation; renal compensation for respiratory acidosis takes days.

Cardiac output measurement: thermodilution, Fick principle, and echocardiography; stroke volume depends on preload, afterload, and contractility.

Cranial nerve lesions: facial nerve palsy causes ipsilateral facial weakness; hypoglossal lesion causes tongue deviation to the affected side.

Chemotherapy: alkylating agents cross-link DNA; antimetabolites such as methotrexate inhibit dihydrofolate reductase; vinca alkaloids inhibit microtubules.

Adverse drug reactions: type A are dose-dependent and predictable; type B are idiosyncratic; type C are chronic; type D are delayed.

Viral hepatitis: hepatitis A and E spread faeco-orally; B, C, D spread parenterally; hepatitis B has a vaccine.

Fungal infections: Candida treated with fluconazole; Aspergillus with voriconazole; Cryptococcus with amphotericin B plus flucytosine.

Medicolegal autopsy: types include clinical, pathological, and medicolegal; consent required except in medicolegal cases ordered by magistrate.

Community medicine: specificity and sensitivity of a test are used to calculate predictive values; prevalence affects PPV and NPV.

Bias in research: selection bias, information bias, confounding; randomisation and adjustment reduce confounding.

Antisepsis: alcohol-based hand rub is preferred for routine hand hygiene; soap and water when hands are visibly soiled.

Upper GI bleeding: variceal bleed treated with terlipressin and endoscopic band ligation; peptic ulcer bleed with proton pump inhibitor and endoscopic therapy.

Gallstone disease: biliary colic, cholecystitis, cholangitis; Charcot triad is fever, jaundice, right upper quadrant pain; ERCP for choledocholithiasis.

Obstructed labour: diagnosed by poor progress with moulding and caput; manage with caesarean section or instrumental delivery depending on station.

Antepartum haemorrhage: placenta praevia presents with painless bleeding; abruption with painful bleeding and uterine tenderness.

Paediatric seizures: febrile seizures are common between 6 months and 5 years; simple febrile seizure lasts <15 min and does not recur in 24 h.

Diabetes in pregnancy: insulin is preferred when oral agents insufficient; target fasting <95 mg/dL and 2-h postprandial <120 mg/dL.

Fractures: open fractures need antibiotics and debridement; compartment syndrome shows pain out of proportion and passive stretch pain.

Chronic obstructive pulmonary disease: smoking cessation is the only intervention that slows decline; influenza and pneumococcal vaccination recommended.

Cranial fossae: anterior contains frontal lobe; middle contains temporal lobe and pituitary; posterior contains cerebellum and brainstem.

Respiratory mechanics: inspiration is active via diaphragm and external intercostals; expiration is passive at rest.

Cardiac action potential: phase 0 Na+ influx, phase 1 transient K+ efflux, phase 2 Ca2+ influx plateau, phase 3 K+ efflux, phase 4 resting.

Amino acid derivatives: tyrosine gives thyroid hormones and catecholamines; tryptophan gives serotonin and niacin; histidine gives histamine.

Glycolysis regulation: hexokinase, phosphofructokinase-1, and pyruvate kinase are key regulatory enzymes.

Renal handling: glucose reabsorbed in proximal tubule via SGLT2; amino acids via cotransport; hydrogen ions secreted for acid–base balance.

Lung compliance: surfactant from type II pneumocytes reduces surface tension; deficiency causes respiratory distress syndrome in preterm infants.

Neurotransmitters: acetylcholine at neuromuscular junction; dopamine in substantia nigra; GABA is inhibitory; glutamate is excitatory.

Haematology: iron deficiency shows microcytic hypochromic anaemia with low ferritin and high TIBC; thalassaemia shows normal ferritin.

Leukaemia: acute lymphoblastic commonest in children; acute myeloid in adults; chronic myeloid shows Philadelphia chromosome t(9;22).

Diuretics: loop diuretics inhibit Na+/K+/2Cl− cotransporter in thick ascending limb; thiazides act on distal convoluted tubule.

Antihypertensives: ACE inhibitors cause dry cough due to bradykinin; ARBs avoid cough; calcium channel blockers cause ankle oedema.

Sterilisation and disinfection: glutaraldehyde for endoscopes; chlorhexidine for skin antisepsis; sodium hypochlorite for surfaces.

Poisoning: methanol causes metabolic acidosis and visual loss; treat with fomepizole or ethanol and haemodialysis.

Community medicine: case fatality rate = deaths from disease / diagnosed cases × 100; attack rate used in outbreaks.

Forensic ballistics: entry wound shows inverted margins and tattooing; exit wound is larger with everted margins.

Myocardial infarction: inferior leads II, III, aVF; anterior V1–V4; lateral I, aVL, V5–V6; posterior shows reciprocal ST depression in V1–V3.

Heart failure: pulmonary oedema treated with oxygen, diuretic, nitrate, and non-invasive ventilation; morphine no longer routine.

Thyroidectomy complications: hypocalcaemia from parathyroid injury; haematoma causing airway obstruction; thyroid storm from manipulation.

Breast abscess: common in lactating women; treat with ultrasound-guided aspiration and antibiotics; continue breastfeeding.

Ovarian torsion: sudden severe unilateral pain with nausea; ultrasound shows enlarged ovary with reduced Doppler flow; surgical detorsion.

Paediatric diarrhoea: assess dehydration; ORS for some dehydration; intravenous fluids for severe dehydration; continue feeding.

Hypertensive emergency: reduce mean arterial pressure by no more than 25% in first hour; use intravenous labetalol or nicardipine.

Prostate: benign hyperplasia causes lower urinary tract symptoms; PSA not specific; biopsy guided by MRI and transrectal ultrasound.

Brachial artery: runs medial to biceps, palpable at cubital fossa; radial artery used for pulse; ulnar artery forms superficial palmar arch.

Physiology of pain: nociceptors transmit via A-delta (fast, sharp) and C fibres (slow, dull); gate control theory modulates pain at dorsal horn.

Energy metabolism: basal metabolic rate highest in infancy; thyroid hormones increase BMR; brown fat generates heat via uncoupling protein.

Lipoproteins: LDL receptor deficiency causes familial hypercholesterolaemia; HDL inversely related to cardiovascular risk.

DNA repair: nucleotide excision repair for UV damage; mismatch repair defects cause Lynch syndrome; BRCA mutations impair homologous recombination.

Muscle contraction: excitation–contraction coupling requires calcium release from sarcoplasmic reticulum via ryanodine receptors.

Respiratory control: medulla sets rhythm; peripheral chemoreceptors respond to low PaO2; central respond to high PaCO2.

Hormones of pregnancy: hCG maintains corpus luteum; progesterone maintains endometrium; human placental lactogen alters maternal metabolism.

Nephrotic vs nephritic: nephritic shows haematuria, hypertension, oliguria; nephrotic shows heavy proteinuria and oedema.

Cirrhosis: portal hypertension leads to varices, ascites, hepatic encephalopathy; treat encephalopathy with lactulose and rifaximin.

Antidepressants: SSRIs first-line; serotonin syndrome from excess serotonergic activity; MAO inhibitors require dietary tyramine restriction.

Antipsychotics: typical cause extrapyramidal symptoms; atypical cause metabolic syndrome; clozapine requires blood count monitoring.

Hospital-acquired infection: common organisms include MRSA, Clostridioides difficile, and multidrug-resistant Gram-negative bacteria.

Medicolegal identification: fingerprints, DNA, dental records, and scars; age estimation from ossification centres and teeth.

Community medicine: maternal mortality ratio = maternal deaths per 100,000 live births; India targets reduction under SDG 3.

Meta-analysis: combines studies with effect sizes; heterogeneity assessed by I² statistic; publication bias assessed by funnel plot.

Chronic kidney disease: anaemia from erythropoietin deficiency; metabolic acidosis from reduced acid excretion; hyperphosphataemia with hypocalcaemia.

Liver disease: ascites treated with salt restriction, spironolactone and furosemide; paracentesis for tense ascites.

Surgery: wound classification clean, clean-contaminated, contaminated, dirty; prophylactic antibiotic given within 60 min before incision.

Obstetrics: shoulder dystocia managed with McRoberts manoeuvre and suprapubic pressure; avoid fundal pressure.

Preterm labour: corticosteroids (dexamethasone) given between 24 and 34 weeks for fetal lung maturity; magnesium sulphate for neuroprotection.

Paediatric congenital heart disease: ventricular septal defect is commonest; cyanotic lesions include tetralogy of Fallot and transposition.

Gout: monosodium urate crystals are needle-shaped and negatively birefringent; acute attack treated with NSAIDs or colchicine.

Osteoarthritis: weight-bearing joint pain worse with activity; joint space narrowing and osteophytes on X-ray.

Upper limb nerves: radial nerve supplies extensors; median nerve supplies thenar muscles; ulnar nerve supplies intrinsic hand muscles.

Physiology of vision: rods for dim light, cones for colour; vitamin A deficiency causes night blindness; optic nerve carries visual signals.

Protein-energy malnutrition: marasmus shows severe wasting; kwashiorkor shows oedema and hypoalbuminaemia.

Enzyme deficiency diseases: phenylketonuria (phenylalanine hydroxylase), alkaptonuria (homogentisate oxidase), maple syrup urine disease (branched-chain ketoacid dehydrogenase).

Cardiac cycle timings: systole ~0.3 s, diastole ~0.5 s; isovolumetric contraction and relaxation are valve-closed phases.

Glomerular filtration: filtration barrier consists of fenestrated endothelium, basement membrane, and podocyte foot processes.

Vitamin D metabolism: skin synthesis, hepatic 25-hydroxylation, renal 1α-hydroxylation; deficiency causes rickets and osteomalacia.

Neuroanatomy: basal ganglia control movement; substantia nigra degeneration causes Parkinson disease; thalamus relays sensory input.

Transfusion medicine: ABO compatibility; crossmatch before transfusion; febrile reaction commonest; anaphylaxis from IgA deficiency.

Tumour grading vs staging: grade describes differentiation; stage describes extent and determines prognosis.

Antifungal drugs: amphotericin B causes nephrotoxicity and hypokalaemia; azoles inhibit ergosterol synthesis; echinocandins inhibit cell wall.

Vaccine types: live attenuated (MMR, BCG), killed (IPV), toxoid (tetanus), subunit (hepatitis B), mRNA (COVID-19).

Postmortem examination: external examination, internal examination, histopathology, toxicology; cause, manner, and mechanism of death documented.

Community medicine: DALY combines years of life lost and years lived with disability; used to measure disease burden.

Outbreak investigation: verify diagnosis, define cases, find source, implement control, communicate findings.

Ethics: informed consent, confidentiality, and institutional ethics committee approval are required for research on human participants.

Stroke: ischaemic stroke treated with antiplatelet and statin; haemorrhagic stroke managed with blood pressure control and neurosurgical review.

Epilepsy: first-line for focal seizures is carbamazepine or lamotrigine; for generalised tonic-clonic is sodium valproate or lamotrigine.

Appendicectomy: laparoscopic preferred; complications include wound infection, abscess, and ileus; Alvarado score guides diagnosis.

Caesarean section: indications include fetal distress, obstructed labour, placenta praevia, previous classical section; complications include haemorrhage and infection.

Gestational trophoblastic disease: complete mole shows snowstorm appearance and high hCG; follow hCG to zero; chemotherapy for persistent disease.

Paediatric asthma: diagnosis clinical; spirometry in older children; avoid beta-blockers; manage exacerbations with oxygen and salbutamol.

Hypothyroidism: treat with levothyroxine; start low in elderly and cardiac disease; monitor TSH after 6–8 weeks.

Fracture management: reduction, immobilisation, rehabilitation; open reduction internal fixation for unstable or intra-articular fractures.

Thoracic anatomy: right main bronchus is wider and more vertical; left lung has cardiac notch; diaphragm has aortic, oesophageal, and caval openings.

Physiology of hearing: sound waves vibrate tympanic membrane, ossicles, and cochlea; organ of Corti transduces signals to auditory nerve.

Carbohydrate metabolism: insulin promotes glycogen synthesis; glucagon promotes glycogenolysis; cortisol promotes gluconeogenesis.

Fatty acid oxidation: carnitine shuttle transports fatty acids into mitochondria; deficiency causes hypoketotic hypoglycaemia.

Blood pressure regulation: baroreceptors in carotid sinus and aortic arch; renin–angiotensin–aldosterone system raises blood pressure.

Lung function tests: obstructive shows reduced FEV1/FVC; restrictive shows reduced FVC with normal or increased ratio.

Neurotransmitter receptors: nicotinic receptors are ligand-gated ion channels; muscarinic are G-protein coupled; adrenergic are G-protein coupled.

Cell cycle: G1, S, G2, M; p53 arrests cycle at G1 for DNA repair; cyclins and CDKs drive progression.

Inflammation mediators: prostaglandins cause pain and fever; leukotrienes cause bronchoconstriction; histamine causes vasodilation.

Anaemia: iron deficiency commonest worldwide; vitamin B12 deficiency causes macrocytic anaemia with neurological signs; folate deficiency without neurological signs.

Antibiotics: penicillin G for Streptococcus; ceftriaxone for meningitis; vancomycin for MRSA; metronidazole for anaerobes.

HIV: diagnosis by ELISA screening and Western blot or nucleic acid test; CD4 count guides prophylaxis; antiretroviral therapy for all.

Sterilisation: autoclave fails if air not removed; Bowie–Dick test checks vacuum; biological indicator confirms spore kill.

Forensic toxicology: alcohol estimated by gas chromatography; carbon monoxide by spectrophotometry; organophosphates by cholinesterase assay.

Community medicine: immunisation coverage assessed by cluster sampling; 30-cluster survey used for vaccination coverage.

Screening programme: lead-time bias and length bias affect survival; randomised trials reduce bias.

Acute coronary syndrome: aspirin, P2Y12 inhibitor, anticoagulation, and reperfusion; STEMI needs primary PCI within 90 min of first medical contact.

Hypertension: lifestyle modification plus medication; target <140/90 generally; <130/80 in diabetes and chronic kidney disease.

Trauma: secondary survey includes head-to-toe examination; FAST and CT for internal injury; damage control surgery for unstable patients.

Obstetrics: partograph monitors labour progress; alert line and action line guide intervention for prolonged labour.

Menstrual disorders: heavy menstrual bleeding evaluated with ultrasound and endometrial biopsy if over 45 years.

Paediatric growth: failure to thrive evaluated with weight, height, head circumference; coeliac disease and cystic fibrosis are causes.

Diabetes: metformin first-line; add SGLT2 inhibitor or GLP-1 receptor agonist in cardiovascular or renal disease.

Pneumothorax: tension pneumothorax treated with needle decompression in second intercostal space midclavicular line, then chest drain.

Abdominal anatomy: foregut supplied by coeliac trunk, midgut by superior mesenteric artery, hindgut by inferior mesenteric artery.

Physiology of digestion: gastric acid kills bacteria and activates pepsin; bile emulsifies fat; pancreatic enzymes digest protein, fat, and carbohydrate.

Metabolic response to injury: cortisol and catecholamines raise glucose; insulin resistance occurs; protein catabolism increases.

Lipid profile: total cholesterol, LDL, HDL, triglycerides; LDL calculated by Friedewald formula when triglycerides <400 mg/dL.

Acid–base disorders: anion gap = Na+ − (Cl− + HCO3−); high gap in ketoacidosis, lactic acidosis, renal failure, toxins.

Neurotransmission: dopamine pathways include nigrostriatal, mesolimbic, mesocortical, and tuberoinfundibular.

Renal physiology: countercurrent multiplier in loop of Henle creates medullary concentration gradient; ADH increases water permeability.

Genetic inheritance: autosomal dominant appears in every generation; autosomal recessive affects siblings; X-linked affects males.

Necrosis vs apoptosis: necrosis causes inflammation and cell swelling; apoptosis is programmed, energy-dependent, and non-inflammatory.

Tumour spread: direct invasion, lymphatic spread, haematogenous spread, transcoelomic spread; carcinomas spread via lymphatics, sarcomas via blood.

Pharmacology: bioavailability is fraction of dose reaching systemic circulation; first-pass metabolism reduces oral bioavailability.

Antibiotic prophylaxis: indicated for surgery, rheumatic fever, meningococcal contacts, and asplenia; choice depends on organism.

Viral structure: DNA or RNA genome, capsid, envelope; influenza has segmented RNA and antigenic shift.

Autopsy: cause of death is disease or injury; manner is natural, accidental, suicidal, or homicidal; mechanism is pathophysiological process.

Community medicine: incidence density uses person-time; cumulative incidence uses population at risk.

Biostatistics: mean, median, mode; standard deviation measures spread; normal distribution covers 95% within 1.96 SD.

Chronic obstructive pulmonary disease: inhaled bronchodilators are mainstay; pulmonary rehabilitation improves symptoms; long-term oxygen for severe hypoxaemia.

Cirrhosis: hepatocellular carcinoma surveillance with ultrasound every 6 months; alpha-fetoprotein adjunct; liver transplant for decompensated disease.

Hernia: inguinal hernia repair with mesh; femoral hernia higher risk of strangulation; urgent surgery for strangulation.

Obstetrics: postpartum haemorrhage treated with uterine massage, oxytocin, tranexamic acid, and balloon tamponade if needed.

Endometriosis: presents with dysmenorrhoea and infertility; diagnosis by laparoscopy; treat with hormonal therapy or surgery.

Paediatric meningitis: lumbar puncture if stable; empirical ceftriaxone plus vancomycin; dexamethasone before or with first antibiotic.

Rheumatoid arthritis: anti-CCP and rheumatoid factor; treat with methotrexate; biologics for inadequate response.

Fracture complications: fat embolism after long bone fracture; deep vein thrombosis; malunion and non-union.

Head and neck anatomy: facial nerve exits stylomastoid foramen; trigeminal has ophthalmic, maxillary, mandibular divisions; internal jugular vein drains brain.

Physiology of exercise: cardiac output increases, muscle blood flow rises, oxygen extraction increases; anaerobic threshold marks lactate rise.

Protein synthesis: transcription in nucleus, translation on ribosomes; post-translational modification in endoplasmic reticulum and Golgi.

Cholesterol transport: LDL receptor-mediated endocytosis; HDL reverse transport; statins reduce synthesis and upregulate LDL receptors.

Endocrine pancreas: beta cells secrete insulin; alpha cells glucagon; delta cells somatostatin; PP cells pancreatic polypeptide.

Respiratory gas transport: oxygen bound to haemoglobin and dissolved; carbon dioxide as bicarbonate, carbamino compounds, and dissolved.

Nerve conduction: myelinated fibres saltatory conduction; demyelination slows conduction; local anaesthetics block sodium channels.

Body temperature: fever from pyrogens raises hypothalamic set point; hyperthermia is failure of thermoregulation.

Haemostasis: platelet adhesion via von Willebrand factor, activation, aggregation via glycoprotein IIb/IIIa; anticoagulants target coagulation cascade.

Thrombosis: arterial thrombi are platelet-rich; venous thrombi are fibrin-rich; treat arterial with antiplatelets, venous with anticoagulants.

Pharmacology of asthma: short-acting beta-2 agonists for relief; inhaled corticosteroids for control; leukotriene antagonists as add-on.

Tuberculosis drugs: isoniazid, rifampicin, pyrazinamide, ethambutol; monitor liver function; ethambutol causes optic neuritis.

Bacterial culture: blood agar for Streptococcus, chocolate agar for Haemophilus, MacConkey for Enterobacteriaceae.

Forensic medicine: consent for autopsy in medicolegal cases is not required from relatives; police request required.

Community medicine: under-five mortality rate = deaths under 5 per 1,000 live births; reflects child health and nutrition.

Epidemiology: outbreak investigation uses case definition, line listing, and epidemic curve to identify source and mode of spread.

Acute kidney injury: prerenal from hypovolaemia; renal from acute tubular necrosis; postrenal from obstruction; urine sodium helps differentiate.

Hyperkalaemia: ECG shows peaked T waves, widened QRS; treat with calcium gluconate, insulin–dextrose, salbutamol, and dialysis if severe.

Surgery: acute abdomen requires prompt assessment; perforation shows free gas under diaphragm; peritonitis needs laparotomy.

Obstetrics: placenta accreta spectrum risk with previous caesarean and placenta praevia; manage with multidisciplinary team and hysterectomy if needed.

Infertility: evaluate both partners; semen analysis, ovulation assessment, tubal patency; IVF for tubal factor and unexplained infertility.

Paediatric jaundice: phototherapy for significant hyperbilirubinaemia; exchange transfusion for severe cases; kernicterus is a complication.

Thyroid storm: fever, tachycardia, agitation, altered consciousness; treat with propylthiouracil, beta-blocker, iodine, and steroids.

Osteomyelitis: Staphylococcus aureus commonest; MRI for early diagnosis; antibiotics and surgical debridement.

Pelvic anatomy: ureter crosses pelvic brim anterior to common iliac artery; internal iliac artery supplies pelvic organs; pudendal nerve supplies perineum.

Physiology of micturition: detrusor muscle contracts, internal sphincter relaxes; pontine micturition centre coordinates; parasympathetic drives voiding.

Hormonal regulation of calcium: PTH raises serum calcium; calcitonin lowers it; vitamin D increases intestinal absorption.

Purine metabolism: uric acid is end product in humans; gout from urate crystal deposition; allopurinol inhibits xanthine oxidase.

Cardiac output: preload from venous return; afterload from vascular resistance; contractility from sympathetic stimulation.

Enzyme inhibitors: statins inhibit HMG-CoA reductase; methotrexate inhibits dihydrofolate reductase; allopurinol inhibits xanthine oxidase.

Respiratory regulation: chemoreceptors respond to PaCO2, pH, and PaO2; central chemoreceptors respond to CSF pH.

DNA mutations: point mutation, insertion, deletion, frameshift; tumour suppressor loss requires two hits (Knudson hypothesis).

Cell cycle and cancer: oncogenes promote growth; tumour suppressors inhibit; apoptosis evasion is a hallmark of cancer.

Anaemia: sickle cell disease shows sickle-shaped cells and target cells; thalassaemia shows microcytosis with normal iron.

Antibiotics: aminoglycosides cause nephrotoxicity and ototoxicity; vancomycin causes red man syndrome if infused rapidly.

Vaccines: live vaccines provide long-lasting immunity; killed vaccines require boosters; adjuvants enhance immune response.

Infection control: isolation precautions for tuberculosis, measles, and varicella are airborne; hand hygiene prevents cross-infection.

Medicolegal: Section 174 CrPC deals with police inquest; Section 176 CrPC with magistrate inquest; consent for medical examination.

Community medicine: primary health centre covers about 30,000 population in plains and 20,000 in hilly areas.

Screening: sensitivity and specificity trade-off; lowering cutoff increases sensitivity but reduces specificity.

Pneumonia: community-acquired commonest organism Streptococcus pneumoniae; hospital-acquired includes Pseudomonas and MRSA.

Heart failure: ejection fraction measured by echocardiography; BNP elevated in heart failure; treat congestion with diuretics.

Surgery: thyroid swelling evaluated with ultrasound and FNAC; papillary carcinoma commonest; total thyroidectomy for bilateral disease.

Obstetrics: fetal heart monitoring with cardiotocography; late decelerations suggest placental insufficiency; variable decelerations suggest cord compression.

Menopause: hormone replacement therapy for vasomotor symptoms; risk of venous thromboembolism and breast cancer; use lowest effective dose.

Paediatric immunisation: BCG, hepatitis B, OPV at birth; DPT, Hib, rotavirus, pneumococcal at 6, 10, 14 weeks.

Diabetes: diabetic ketoacidosis treated with intravenous fluids, insulin, and potassium; monitor glucose and ketones.

Fracture: Colles fracture shows dinner-fork deformity; scaphoid fracture risk of avascular necrosis; immobilise and follow up.

Upper limb anatomy: rotator cuff muscles supraspinatus, infraspinatus, teres minor, subscapularis; supraspinatus initiates abduction.

Physiology of sleep: REM sleep shows rapid eye movements and dreaming; non-REM stages include slow-wave sleep; sleep cycle ~90 min.

Carbohydrate digestion: salivary amylase in mouth; pancreatic amylase in duodenum; brush border enzymes convert disaccharides to monosaccharides.

Lipid metabolism: beta-oxidation in mitochondria; ketogenesis in liver; ketone bodies used by brain and muscle.

Acid–base: metabolic alkalosis shows high bicarbonate and low chloride in vomiting; treat with saline and potassium.

Cardiac electrophysiology: SA node has highest automaticity; AV node slows conduction; Purkinje fibres rapidly conduct to ventricles.

Renal regulation: juxtaglomerular apparatus secretes renin; macula densa senses sodium chloride; angiotensin II raises blood pressure.

Neuroanatomy: cerebral cortex lobes frontal, parietal, temporal, occipital; motor cortex in precentral gyrus; sensory in postcentral gyrus.

Tumour markers: AFP, CEA, CA-125, PSA, hCG; used for monitoring, not diagnosis; false positives occur in benign conditions.

Inflammation: acute phase reactants include C-reactive protein, ferritin, fibrinogen; ESR raised in inflammation.

Pharmacology: half-life determines dosing frequency; steady state after 4–5 half-lives; loading dose achieves rapid therapeutic level.

Antibiotic resistance: MRSA resistance via altered penicillin-binding protein; ESBLs hydrolyse cephalosporins; carbapenems reserved for resistant organisms.

Microbiology: Gram stain, culture, biochemical tests, and molecular methods; PCR for rapid detection of pathogens.

Forensic medicine: injury classification includes abrasion, contusion, laceration, incised wound, stab wound, firearm wound.

Community medicine: epidemiological triad is agent, host, environment; disease control targets one or more components.

Biostatistics: chi-square test for categorical data; t-test for continuous data; ANOVA for more than two groups.

Stroke: transient ischaemic attack is a warning; urgent assessment and antiplatelet therapy; carotid endarterectomy for symptomatic stenosis.

Hypertension: secondary causes include renal disease, primary aldosteronism, phaeochromocytoma, Cushing syndrome, coarctation of aorta.

Surgery: wound healing by primary intention, secondary intention, and tertiary intention; factors delaying healing include infection, diabetes, steroids.

Obstetrics: multiple pregnancy risk of preterm labour, pre-eclampsia, gestational diabetes; monitor with ultrasound and fetal surveillance.

Endometrial cancer: postmenopausal bleeding is the classic presentation; diagnosis by endometrial biopsy; treat with surgery.

Paediatric nephrotic syndrome: minimal change disease commonest; treat with corticosteroids; relapses common.

Diabetes: hypoglycaemia treated with oral glucose or intravenous dextrose; glucagon for severe cases; monitor blood glucose.

Osteoporosis: fragility fracture of hip, wrist, vertebra; DXA scan; treat with bisphosphonates and calcium/vitamin D.

Lower limb anatomy: femoral nerve supplies quadriceps; sciatic nerve supplies hamstrings and leg muscles; tibial nerve supplies sole.

Physiology of urine formation: filtration, reabsorption, secretion; proximal tubule reabsorbs most filtered solutes; loop of Henle creates gradient.

Metabolic pathways: glycolysis in cytoplasm; TCA cycle in mitochondria; oxidative phosphorylation in inner mitochondrial membrane.

Hormones: insulin, glucagon, cortisol, thyroid hormones regulate metabolism; growth hormone promotes growth via IGF-1.

Cardiac cycle: S1 and S2 heart sounds; murmurs from turbulent flow; valvular stenosis and regurgitation cause different murmurs.

Respiratory physiology: ventilation–perfusion ratio highest at apex, lowest at base; hypoxia causes vasoconstriction in lungs.

Genetics: autosomal dominant, autosomal recessive, X-linked; mitochondrial inheritance from mother; trinucleotide repeat disorders.

Neurotransmitters: acetylcholine, dopamine, noradrenaline, serotonin, GABA, glutamate; each has specific receptors and functions.

Cell injury: reversible cell injury shows swelling; irreversible shows membrane damage and mitochondrial dysfunction; apoptosis is programmed.

Inflammation: acute inflammation shows vasodilation, increased permeability, neutrophil infiltration; chronic shows macrophages and lymphocytes.

Pharmacology: agonists activate receptors; antagonists block; partial agonists produce submaximal response; inverse agonists reduce constitutive activity.

Antibiotics: beta-lactams inhibit cell wall; aminoglycosides inhibit protein synthesis; fluoroquinolones inhibit DNA gyrase; macrolides inhibit 50S.

Microbiology: bacteria classified by Gram stain, shape, oxygen requirement; viruses by genome and envelope; fungi by morphology.

Forensic medicine: autopsy findings in drowning include froth at mouth, water in stomach, diatoms in tissues.

Community medicine: health indicators include life expectancy, infant mortality rate, maternal mortality ratio, literacy rate.

Biostatistics: sensitivity, specificity, predictive values; prevalence affects predictive values; likelihood ratios summarise test performance.

Myocardial infarction: complications include arrhythmia, heart failure, cardiogenic shock, papillary muscle rupture, ventricular septal defect.

Heart failure: NYHA classification I–IV based on symptoms; treat with diuretics, ACE inhibitors, beta-blockers, mineralocorticoid antagonists.

Surgery: appendicitis commonest cause of acute abdomen; McBurney point tenderness; Alvarado score guides management.

Obstetrics: pre-eclampsia treated with antihypertensives and magnesium sulphate; delivery is definitive treatment.

Ovarian cancer: CA-125 for monitoring; surgery and chemotherapy; BRCA mutations increase risk.

Paediatric asthma: inhaled corticosteroids for control; short-acting beta-2 agonists for relief; avoid triggers.

Thyroid disease: hyperthyroidism treated with antithyroid drugs, radioiodine, or surgery; hypothyroidism with levothyroxine.

Fracture: open fracture requires antibiotics, tetanus prophylaxis, debridement, and fixation.

Anatomy of heart: right atrium receives superior and inferior vena cava; right ventricle pumps to lungs; left atrium receives pulmonary veins; left ventricle pumps to aorta.

Physiology of respiration: inspiration active, expiration passive; surfactant reduces surface tension; compliance measures lung expandability.

Biochemistry of blood: haemoglobin carries oxygen; plasma proteins include albumin, globulins, fibrinogen; albumin maintains oncotic pressure.

Enzyme kinetics: Michaelis–Menten equation; Lineweaver–Burk plot; competitive inhibition raises Km, non-competitive lowers Vmax.

Metabolism: glycolysis, TCA cycle, oxidative phosphorylation; fatty acid oxidation; amino acid metabolism; urea cycle.

Endocrinology: hypothalamus–pituitary axis; negative feedback; hormone receptors; second messengers.

Renal physiology: glomerular filtration, tubular reabsorption, secretion; countercurrent mechanism; acid–base balance.

Neuroanatomy: brainstem, cerebellum, basal ganglia, thalamus, hypothalamus; cranial nerves; spinal cord tracts.

Pathology: cell injury, inflammation, repair, neoplasia, haemodynamic disorders, genetic diseases, immunopathology.

Pharmacology: pharmacokinetics, pharmacodynamics, drug interactions, adverse reactions, therapeutic uses.

Microbiology: bacteriology, virology, mycology, parasitology, immunology, sterilisation, infection control.

Forensic medicine: medicolegal aspects, autopsy, injury classification, poisoning, identification, asphyxia.

Community medicine: epidemiology, biostatistics, health programmes, maternal and child health, environmental health.

Pathology: tumour grading and staging; benign vs malignant; metastasis routes.

Pharmacology: antibiotics, antivirals, antifungals, antitubercular drugs, antimalarials.

Microbiology: culture media, staining techniques, biochemical tests, molecular diagnostics.

Medicine: cardiovascular, respiratory, gastrointestinal, endocrine, renal, neurological disorders; diagnosis and management.

Surgery: general surgery, orthopaedics, urology, neurosurgery, plastic surgery; operative principles and complications.

Obstetrics and gynaecology: antenatal care, labour, delivery, postpartum care, gynaecological disorders.

Paediatrics: growth and development, immunisation, common childhood illnesses, neonatal care.

Allied specialties: dermatology, psychiatry, ophthalmology, ENT, anaesthesiology, radiology.

Clinical examination: history, general examination, systemic examination, investigations.

Emergency management: ABCDE approach, resuscitation, trauma care, poisoning.

Preventive medicine: screening, vaccination, health education, lifestyle modification.

Anatomy: gross anatomy, histology, embryology, neuroanatomy; regional and systemic approaches.

Physiology: cardiovascular, respiratory, renal, gastrointestinal, endocrine, nervous, reproductive systems.

Biochemistry: biomolecules, enzymes, metabolism, molecular biology, genetics, nutrition.

Anatomy: upper limb, lower limb, thorax, abdomen, pelvis, head and neck, brain.

Physiology: homeostasis, cell physiology, blood, muscle, digestion, metabolism, temperature regulation.

Biochemistry: carbohydrate, lipid, protein, nucleotide metabolism; vitamins, minerals, hormones.

Anatomy: clinical correlations, surface anatomy, radiological anatomy.

Physiology: clinical physiology, pathophysiology, diagnostic tests.

Biochemistry: clinical biochemistry, metabolic disorders, genetic diseases.

Pathology: general pathology, systemic pathology, haematology, cytology, histopathology.

Pharmacology: general pharmacology, systemic pharmacology, chemotherapy, toxicology.

Microbiology: general microbiology, systemic microbiology, immunology, parasitology.

Forensic medicine: forensic pathology, clinical forensic medicine, toxicology, medical jurisprudence.

Community medicine: epidemiology, biostatistics, health administration, health education, environmental health.

Pathology: inflammation, repair, neoplasia, haemodynamic disorders, immunopathology, genetic diseases.

Pharmacology: pharmacokinetics, pharmacodynamics, drug interactions, adverse drug reactions, therapeutic drug monitoring.

Microbiology: sterilisation, disinfection, culture media, staining, biochemical reactions, serology, molecular methods.

Medicine: history taking, physical examination, investigations, diagnosis, treatment, follow-up.

Surgery: preoperative assessment, operative technique, postoperative care, complications.

Obstetrics: antenatal care, intrapartum care, postpartum care, family planning.

Gynaecology: menstrual disorders, infertility, infections, tumours, menopause.

Paediatrics: growth, development, nutrition, immunisation, common diseases, emergencies.

Allied specialties: dermatology, psychiatry, ophthalmology, ENT, orthopaedics, anaesthesiology.

Clinical skills: communication, counselling, ethical practice, evidence-based medicine.

Emergency: resuscitation, trauma, poisoning, obstetric emergencies, paediatric emergencies.

Anatomy: bones, joints, muscles, nerves, blood vessels; regional anatomy with clinical correlations.

Physiology: cell membrane transport, action potential, muscle contraction, synaptic transmission.

Biochemistry: enzyme kinetics, metabolic pathways, energy production, molecular biology.

Anatomy: thorax, abdomen, pelvis, perineum, upper and lower limbs, head and neck.

Physiology: cardiovascular system, respiratory system, renal system, gastrointestinal system, endocrine system.

Biochemistry: carbohydrate metabolism, lipid metabolism, protein metabolism, nucleotide metabolism.

Anatomy: embryology, histology, neuroanatomy.

Physiology: blood, immunity, temperature regulation, exercise physiology, environmental physiology.

Biochemistry: vitamins, minerals, nutrition, clinical biochemistry, genetic disorders.

Pathology: cell injury, inflammation, repair, neoplasia, haemodynamic disorders, immunopathology.

Pharmacology: pharmacokinetics, pharmacodynamics, drug interactions, adverse reactions, therapeutic uses.

Microbiology: bacteriology, virology, mycology, parasitology, immunology, sterilisation.

Forensic medicine: autopsy, injury classification, poisoning, identification, asphyxia, medicolegal aspects.

Community medicine: epidemiology, biostatistics, health programmes, maternal and child health, environmental health.

Pathology: haematology, cytology, histopathology, laboratory medicine.

Pharmacology: antibiotics, antivirals, antifungals, antitubercular, antimalarial, anticancer drugs.

Microbiology: culture media, staining, biochemical tests, serology, molecular diagnostics.

Medicine: cardiovascular, respiratory, gastrointestinal, endocrine, renal, neurological disorders.

Surgery: general surgery, orthopaedics, urology, neurosurgery, plastic surgery.

Obstetrics and gynaecology: antenatal care, labour, delivery, postpartum care, gynaecological disorders.

Paediatrics: growth and development, immunisation, common childhood illnesses, neonatal care.

Allied specialties: dermatology, psychiatry, ophthalmology, ENT, anaesthesiology, radiology.

Clinical examination: history, general examination, systemic examination, investigations.

Emergency management: ABCDE approach, resuscitation, trauma care, poisoning.

Preventive medicine: screening, vaccination, health education, lifestyle modification.