Phase I HM-A Integrated Medical Sciences Flashcards

Vocabulary flashcards covering key concepts in anatomy, pharmacology, biochemistry, microbiology, pathology, physiology, public health, and biostatistics from the Phase I HM-A lecture notes.

Physical Activity Guidelines (Moderate Intensity)

Recommended physical activity target of 150-300 minutes of moderate intensity physical activity per week for adults.

Physical Activity Guidelines (Vigorous Intensity)

Recommended physical activity target of 75-150 minutes of vigorous intensity physical activity per week for adults.

Superior Mediastinum

The compartment bounded inferiorly by the transverse plane extending from the manubriosternal joint to the inferior margin of T4 vertebra, containing the trachea, oesophagus, thymus, aortic arch, brachiocephalic trunk, left common carotid artery, subclavian artery, superior vena cava, and brachiocephalic veins.

Transverse Pericardial Sinus

A pericardial passage formed by the bending of the embryonic heart tube, situated with the aorta and pulmonary trunk anteriorly, and the atria and great veins posteriorly.

Crista Terminalis

A smooth internal muscular ridge in the right atrium separating the smooth-walled sinus venarum from the pectinate muscles of the atrium proper, which contains the sinoatrial (SA) node.

Right Coronary Artery (RCA)

A coronary artery originating from the right aortic sinus that supplies the right atrium, most of the right ventricle, part of the left ventricle, the posterior third of the interventricular septum, the SA node in approximately 60% of people, and the AV node in approximately 80% of people.

Cardiac Referred Pain

Pain originating from myocardial ischemia that is perceived as arising from superficial somatic structures, typically the skin of the left upper limb, sharing spinal cord entry segments T1-T4/5.

Thoracolumbar Outflow

The structural origin of the sympathetic nervous system, consisting of preganglionic neuron cell bodies located in the lateral horns of spinal cord segments T1-L2.

Craniosacral Outflow

The structural origin of the parasympathetic nervous system, consisting of preganglionic neurons in brainstem nuclei (Cranial Nerves III, VII, IX, X) and spinal cord segments S2-S4.

Chylomicrons

Large lipoprotein particles synthesized in intestinal enterocytes that transport dietary (exogenous) triglycerides and cholesterol from the gut via the lymphatic system into the bloodstream.

HMG-CoA Reductase

The rate-limiting enzyme in cholesterol biosynthesis that converts HMG-CoA to mevalonate, which serves as the primary target for statin class medications.

Corneal Arcus

A lipid ring of opacity deposited in the peripheral corneal stroma and anterior sclera, serving as a clinical sign of hypercholesterolaemia.

Naloxone

A short-acting competitive opioid receptor antagonist used clinically to rapidly reverse opioid toxicity and respiratory depression.

Disulfiram

An aversion therapy agent for alcohol dependence that inhibits aldehyde dehydrogenase, causing toxic accumulation of acetaldehyde upon ethanol ingestion.

Methadone

A long-acting synthetic full mu-opioid receptor agonist with a half-life of 20-35 hours used in Opioid Substitution Treatment (OST).

Dissociative Anaesthesia

An anaesthetic state produced by ketamine, characterized by NMDA receptor blockade leading to sensory loss, profound analgesia, amnesia, and immobility without complete loss of consciousness.

Blood:Gas Partition Coefficient

A measure of an inhalational anaesthetic's solubility in blood relative to gas, where a lower value indicates faster induction and recovery rates.

Vasa Vasorum

A network of small blood vessels located within the adventitia and outer media of large arteries and veins that provides metabolic support to vessel wall layers.

Continuous Capillaries

Capillaries featuring uninterrupted endothelial linings connected by tight occluding junctions and surrounded by a continuous basement membrane, typical of muscle, lungs, and central nervous tissue.

Bullous Impetigo

A contagious bacterial skin infection caused by Staphylococcus aureus strains producing exfoliative toxin A, characterized by fluid-filled bullae up to $2\,cm$ in diameter that rupture leaving a peripheral collarette.

ESKAPE Pathogens

A group of multi-drug resistant bacterial species responsible for major hospital-acquired infections, comprising Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species.

Minimal Inhibitory Concentration (MIC)

The lowest concentration of an antimicrobial agent required to prevent visible growth of a microorganism in vitro over a specified period, typically 24 hours.

Vulnerable Plaque

An atherosclerotic plaque at high risk of rupture, characterized by a thin fibrous cap ($<65\,\mu m$), a large lipid-rich necrotic core, and dense macrophage infiltration.

Virchow's Triad

The three primary pathophysiological factors contributing to thrombosis: endothelial injury/activation, abnormal blood flow (stasis or turbulence), and hypercoagulability.

Lines of Zahn

Alternating macroscopic and microscopic laminations composed of pale layers of platelets and fibrin interspersed with dark layers of erythrocytes, characteristic of thrombi formed in flowing blood.

Aschoff Bodies

Pathognomonic granulomatous interstitial lesions containing T-lymphocytes, plasma cells, and Anitschkow cells (caterpillar macrophages) found in acute rheumatic carditis.

Enalapril

An oral angiotensin-converting enzyme (ACE) inhibitor that reduces total peripheral resistance, afterload, and aldosterone secretion.

Ivabradine

A selective inhibitor of the hyperpolarization-activated cyclic nucleotide-gated funny current ($I_f$) in the sinoatrial node, used to reduce heart rate without affecting inotropy.

Frank-Starling Mechanism

The intrinsic mechanical principle of cardiac muscle wherein an increase in end-diastolic volume (preload) stretches muscle fibers, increasing the force of subsequent ventricular contraction and stroke volume.

Baroreceptor Reflex

An autonomic homeostatic reflex mediated by stretch-sensitive mechanoreceptors in the carotid sinus and aortic arch that regulates short-term arterial blood pressure.

Fahraeus-Lindqvist Effect

The physiological reduction in apparent blood viscosity observed as blood flows through microvessels with internal diameters smaller than $300\,\mu m$.

Non-Shivering Thermogenesis

Heat production occurring in brown adipose tissue driven by noradrenaline-stimulated upregulation of uncoupling protein 1 (UCP1/thermogenin), which dissipates the mitochondrial proton gradient as heat.

Disability-Adjusted Life Year (DALY)

A quantitative public health metric representing the loss of the equivalent of one year of full health, calculated as the sum of Years of Life Lost (YLL) and Years Lived with Disability (YLD).

Central Limit Theorem

A fundamental statistical principle stating that the distribution of sample means approaches a normal distribution as the sample size increases, regardless of the underlying population distribution shape.

Null Hypothesis ($H_0$)

A foundational statement in statistical hypothesis testing proposing that no true difference or effect exists between variables, and any observed divergence is due to random chance.