All articles starting with G
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Gastric bypass surgery
Gastric bypass surgery, chiefly the Roux-en-Y gastric bypass (RYGB), is a bariatric operation creating a small stomach pouch joined to the small intestine; introduced by Edward Mason in the 1960s, it yields about 31.5% body-weight loss at 3 years and diabetes remission, distinct from sleeve gastrectomy.
Gastric dilatation volvulus
Gastric dilatation volvulus (GDV, bloat, gastric torsion) is a life-threatening canine emergency in which the gas-distended stomach twists on its mesenteric axis, causing shock; it mainly affects large deep-chested breeds and requires decompression, surgery, and gastropexy.
Gastric diverticulum
Gastric diverticulum (stomach diverticulum) is a rare outpouching of the gastric wall, usually congenital, in the posterior fundus. Mostly asymptomatic and incidental; symptomatic GD is a diagnosis of exclusion, treated with PPIs or laparoscopic resection.
Gastric electrical stimulation
Gastric electrical stimulation is an implanted treatment delivering electrical pulses to the stomach wall to reduce nausea and vomiting in drug-refractory gastroparesis, FDA-approved since 2000.
Gastric Emptying
Gastric emptying, the evacuation of food from the stomach into the duodenum, normally takes about 4 hours for 90% of a meal. Measured by scintigraphy (reference standard), 13C breath test, or wireless motility capsule to diagnose gastroparesis or dumping syndrome.
Gastric erosion
Gastric erosion (erosion of stomach, ICD-11 DA60.0) is a superficial mucosal breach not penetrating the muscularis mucosae, usually caused by NSAIDs, aspirin, alcohol, or H. pylori, diagnosed at endoscopy and treated with acid suppression.
Gastric Hypothermia
Gastric hypothermia, or cold gastric lavage, lowers core body temperature by filling the stomach with chilled fluids; studied for heat stroke and GI bleeding, fast in dogs but slow and complication-prone in humans.
Gastric inhibitory polypeptide
Gastric inhibitory polypeptide (GIP), also glucose-dependent insulinotropic polypeptide, is a 42-amino-acid incretin hormone from intestinal K cells that potentiates glucose-dependent insulin secretion; basis of tirzepatide.
Gastric lavage
Gastric lavage, or stomach washout, is a gastrointestinal decontamination procedure for acute oral poisoning using a large-bore orogastric tube. AACT/EAPCCT guidelines say it should not be routine; efficacy falls sharply after 60 minutes.
Gastric linitis plastica
Gastric linitis plastica, also called leather-bottle stomach or Borrmann type 4 gastric cancer, is a diffuse infiltrative gastric adenocarcinoma with signet ring cells and fibrosis, notorious for false-negative superficial biopsies and poor survival.
Gastric lymph nodes
Gastric lymph nodes drain the stomach and are numbered as stations 1–16+ in the Japanese Classification of Gastric Carcinoma, defining D1/D2 lymphadenectomy levels and N staging for gastric cancer.
Gastric phlegmon
Gastric phlegmon, or phlegmonous gastritis (ICD-11 DA42.9), is a rare, rapidly progressive purulent bacterial infection of the stomach wall, usually Streptococcus, with high mortality treated by antibiotics and sometimes gastrectomy.
Gastric polyp
Gastric polyp (stomach polyp), ICD-11 DA44: mucosal or submucosal growth projecting into the stomach lumen, found in about 2% of people and 6% of endoscopies; fundic gland, hyperplastic, and adenomatous types differ in cancer risk.
Gastric ulcer
Gastric ulcer (stomach ulcer, ICD-11 DA60): an acid-and-pepsin breach of the stomach lining over 5 mm deep, mainly caused by Helicobacter pylori or NSAIDs; diagnosed by endoscopy with biopsy, treated with PPIs and eradication therapy.
Gastric varices
Gastric varices are dilated submucosal stomach veins acting as portosystemic collaterals in portal hypertension, classified by Sarin as GOV1, GOV2, IGV1, IGV2; treated with cyanoacrylate, BRTO, or TIPS.
Gastric volvulus
Gastric volvulus: abnormal rotation of the stomach over 180 degrees, organoaxial or mesenteroaxial, causing closed-loop obstruction; Borchardt triad, CT diagnosis, surgical reduction and gastropexy or fundoplication.
Gastrin
Gastrin is a peptide hormone, the second hormone discovered (Edkins, 1905), produced by gastric antrum G cells. It stimulates gastric acid via the CCK2 receptor and ECL-cell histamine; elevated in Zollinger-Ellison syndrome, H. pylori infection, and PPI use.
Gastrin receptor
Gastrin receptor, formally the cholecystokinin B or CCK2 receptor (CCKBR gene, CCK2R), a GPCR binding gastrin and CCK equally; mediates gastric acid secretion, ECL cell growth, and is a theranostic target in tumors.
Gastrin-Releasing Peptide
Gastrin-releasing peptide (GRP) is a 27-amino-acid neuropeptide of the bombesin family, isolated from porcine stomach tissue in 1978, that stimulates gastrin release and transmits itch signals.
Gastrin-releasing peptide receptor
Gastrin-releasing peptide receptor (GRPR, BB2), a class A GPCR binding GRP and bombesin; 384 amino acids, Xp22 gene, Gq/PLC signaling; central itch transmitter and overexpressed target for PET imaging and 177Lu radioligand therapy in prostate, breast, and lung cancers.
Gastrioceras
Gastrioceras, an extinct goniatitid ammonoid genus (family Gastrioceratidae) from the late Bashkirian-Moscovian Carboniferous; index fossil marking the base of the Westphalian (G2/Langsettian zone), with broad, nodose shells found across Europe, North Africa, Asia, and North America.
Gastritis
Gastritis, inflammation of the stomach lining (mucosa), distinct from gastropathy; most often caused by Helicobacter pylori infection, which affects about half the world's population and can lead to ulcers, atrophic gastritis, and stomach cancer.
Gastro-oesophageal reflux disease
Gastro-oesophageal reflux disease (GERD, GORD): chronic condition in which stomach contents reflux into the esophagus causing heartburn, regurgitation, or complications; diagnosed by symptoms, endoscopy, and pH monitoring; treated with PPIs, P-CABs, and antireflux surgery.
Gastrocnemius muscle
Gastrocnemius (musculus gastrocnemius), the superficial two-headed calf muscle; with soleus and plantaris forms the triceps surae. Plantar flexes the ankle, flexes the knee, inserts via the Achilles tendon, innervated by the tibial nerve (S1, S2).
Gastrocnemius recession
Gastrocnemius recession is an orthopedic surgical procedure that lengthens the gastrocnemius aponeurosis to improve ankle dorsiflexion in isolated gastrocnemius tightness, sparing the soleus and Achilles tendon to preserve strength.
Gastrodia
Gastrodia R.Br. is a genus of about 113 accepted leafless, mycoheterotrophic orchids (Orchidaceae, tribe Gastrodieae) native from tropical Africa to Asia, Australia, and New Zealand; G. elata (Tianma) is a traditional Chinese medicine, and some species bear only closed, self-pollinating flowers.
Gastrodia elata
Gastrodia elata (Tianma, 天麻), a fully mycoheterotrophic orchid of Orchidaceae, depends on Mycena and Armillaria fungi, yields the medicinal tuber Gastrodiae Rhizoma, and is used in Chinese medicine and food.
Gastroenteritis
Gastroenteritis, also called stomach flu, is inflammation of the stomach and intestinal lining causing vomiting and diarrhea. Main causes are viruses (norovirus, rotavirus), bacteria, and parasites; the chief danger is dehydration, treated with oral rehydration salts and zinc.
Gastroenteritis due to Rotavirus
Gastroenteritis due to Rotavirus (ICD-11 1A22), rotavirus infection causing severe watery diarrhea and vomiting in infants and young children; fecal-oral spread, oral rehydration treatment, prevented by oral vaccines RotaTeq and Rotarix.
Gastroenterologists
Gastroenterologists, also called GI doctors, are internal medicine subspecialists treating digestive disorders from esophagus to rectum, performing endoscopy and colonoscopy, with hepatology as a liver-focused subspecialty.