2,701 articles
Generalised lymph node enlargement
Generalised lymph node enlargement (generalized lymphadenopathy) is enlarged lymph nodes in two or more noncontiguous body regions, ICD-11 MA01.1, usually signaling systemic infection, malignancy, or autoimmune disease.
Generalized lymphatic anomaly
Generalized lymphatic anomaly (GLA), formerly diffuse systemic lymphangiomatosis, is a rare non-inherited disorder of multifocal dilated lymphatic vessels in multiple organs, distinguished from Gorham-Stout disease by stable medullary bone lesions and treated with sirolimus.
Genetic susceptibility to coronary artery disease
Genetic susceptibility to coronary artery disease is inherited heart-attack risk from many common DNA variants, each with a small effect, distinct from rare single-gene diseases like familial hypercholesterolaemia.
Genetically encoded voltage indicators
Genetically encoded voltage indicators (GEVIs) are engineered fluorescent protein sensors that report membrane voltage optically, allowing noninvasive, cell-type-specific recording with millisecond resolution, mostly in neurons.
Genetics of amyotrophic lateral sclerosis
Genetics of ALS: 5–10% familial, 90–95% sporadic; C9orf72, SOD1, TARDBP, FUS are major genes; 2023 guidelines recommend universal testing; tofersen treats SOD1-ALS.
Genetics of cardiomyopathy
The genetics of cardiomyopathy concerns inherited gene variants that cause heart muscle disease, mainly sarcomere genes like MYBPC3 and MYH7 in hypertrophic cardiomyopathy, usually autosomal dominant with incomplete penetrance.
Get With The Guidelines
Get With The Guidelines (GWTG) is a voluntary hospital quality-improvement registry run by the American Heart Association, with over 2,800 participating US hospitals and 13 million patient records.
Ghrelin
Ghrelin is a 28-amino-acid acylated stomach peptide hormone, the endogenous GHS-R1a ligand discovered by Kojima in 1999, named from Proto-Indo-European "ghre" (grow); it stimulates growth hormone release and hunger.
Giant papillary conjunctivitis
Giant papillary conjunctivitis (GPC), also called contact lens-associated papillary conjunctivitis (CLAPC), is an inflammation of the upper tarsal conjunctiva with giant papillae, mainly in contact lens wearers, causing itching, mucus, and lens intolerance.
Gland
Gland: organized cell aggregation secreting hormones, sweat, saliva, milk, or mucus. Exocrine glands use ducts; endocrine glands release into blood. Covers merocrine/apocrine/holocrine secretion, major glands, disorders, and organoid research.
Glans penis
Glans penis: the conical, bulbous head of the penis, the distal expansion of the corpus spongiosum bearing the external urethral meatus; richly innervated by the dorsal nerve of the penis (S2–S4), supplied by the dorsal and bulb arteries, and central to sexual sensation.
Glasgow Coma Scale
Glasgow Coma Scale (GCS), by Teasdale and Jennett (Lancet 1974): rates eye, verbal, and motor responses; sum score 3–15; severity bands mild 13–15, moderate 9–12, severe <8; standard consciousness assessment in head injury.
Glaucoma
Glaucoma is a group of eye diseases damaging the optic nerve and causing irreversible vision loss; types include open-angle (9 in 10 US cases), angle-closure, congenital, and normal-tension glaucoma, treated by pressure-lowering drops, laser, and surgery.
Glaucoma Drainage Implants
Glaucoma drainage implants (aqueous shunts, tube shunts; Molteno, Baerveldt, Ahmed) are silicone tube-and-plate devices that drain aqueous humor to lower eye pressure in refractory glaucoma, in valved and non-valved designs.
Glaucoma suspect
Glaucoma suspect (borderline glaucoma; ICD-11 9C60, ICD-10 H40.0): a person with elevated IOP, suspicious optic nerve, visual field, or angle findings, or family history, at risk of future glaucoma but not yet glaucomatous.
Glaucoma-ectopia lentis-microspherophakia-stiff joints-short stature syndrome
GEMSS syndrome (glaucoma-ectopia lentis-microspherophakia-stiff joints-short stature), also called Weill-Marchesani syndrome 2, is a rare autosomal dominant FBN1-related disorder with lens dislocation, glaucoma, short stature, and progressive joint stiffness.
Glaucomatous optic neuropathy
Glaucomatous optic neuropathy is the characteristic optic nerve damage in glaucoma, marked by progressive retinal ganglion cell death, optic nerve head excavation, and visual field loss.
Glenoid labrum
Glenoid labrum: fibrocartilaginous rim around the shoulder's glenoid socket, deepening it up to 50% and anchoring biceps tendon and stabilizing ligaments; tears include SLAP, Bankart, and posterior labral lesions.
Glia
Glia (neuroglia) are the non-neuronal cells of the nervous system: astrocytes, oligodendrocytes, microglia, ependymal cells, and Schwann cells. Named by Virchow (1856), they myelinate axons, form the blood-brain barrier, and outnumber neurons only about 1:1.
Glioblastoma
Glioblastoma (GBM, glioblastoma multiforme, grade IV astrocytoma): the most common and aggressive primary adult brain tumor, a fast-growing glial CNS neoplasm treated with surgery, radiotherapy, and temozolomide; median survival about 15 months.
Global Programme to Eliminate Lymphatic Filariasis
Global Programme to Eliminate Lymphatic Filariasis (GPELF), WHO programme launched in 2000 after WHA 50.29; uses annual mass drug administration and morbidity care; 10.3 billion treatments delivered, 23 countries validated, 361 million still requiring MDA in 2025.
Glomerulus (kidney)
The glomerulus, also called the renal glomerulus, is a knot of capillaries in the kidney where blood is filtered to begin forming urine; with Bowman's capsule it forms the renal corpuscle.
Glomus tumor
Glomus tumor (glomangioma): rare benign painful tumor of glomus cells of the Sucquet-Hoyer canal, usually subungual, 1-5% of hand tumors, first described by Masson 1924; distinct from glomus tympanicum paraganglioma.
Glossopharyngeal nerve
Glossopharyngeal nerve (CN IX, nervus glossopharyngeus): ninth cranial nerve from the medulla exiting via the jugular foramen; supplies stylopharyngeus, parotid gland, posterior third of tongue taste, carotid sinus and body; linked to glossopharyngeal neuralgia.
Glucagon
Glucagon: 29-amino-acid pancreatic α-cell peptide hormone raising blood glucose via hepatic GCGR glycogenolysis; rescue drug for severe hypoglycemia (1 mg injectable, 3 mg nasal, dasiglucagon) and target of GLP-1 co-agonists like survodutide.
Glucagon-like peptide-1
Glucagon-like peptide-1 (GLP-1) is an incretin gut hormone from intestinal L-cells that boosts insulin, suppresses glucagon, slows gastric emptying, and curbs appetite; DPP4 gives it a 1–2 minute half-life, spawning agonist drugs like exenatide, liraglutide, and semaglutide.
Glutamate receptor
Glutamate receptor (GluR), ionotropic (AMPA, kainate, NMDA, GluD) and metabotropic families, receptors for glutamate, the brain's main excitatory neurotransmitter; 18 iGluR genes, tetrameric channels, central to synaptic plasticity and neuropsychiatric disease.
Gluteal muscles
The gluteal muscles, or glutei, are a group of four muscles in the buttock that act on the hip joint to extend, abduct, and stabilize the thigh.
Gluteus maximus
Gluteus maximus: the largest gluteal muscle, a quadrangular hip extensor innervated by the inferior gluteal nerve (L5-S2). About 60% larger in humans than apes; central to bipedal running and sitting control.
Glycogen storage disease type II
Glycogen storage disease type II, or Pompe disease, acid maltase deficiency, GAA deficiency: autosomal recessive lysosomal glycogen buildup from acid alpha-glucosidase deficiency, causing infantile cardiomyopathy or late-onset muscle weakness, treated with enzyme replacement therapy.