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Related to gaster: gastritis


the curved, muscular, saclike structure that is an enlargement of the alimentary canal (see digestive system) and lies between the esophagus and the small intestine; called also gaster. (See also Plates.) adj., adj gas´tric.

The wall of the stomach consists of four coats: an outer serous coat; a muscular coat, made up of longitudinal, circular, and oblique muscle fibers; a submucous coat; and a mucous coat or membrane forming the inner lining. The muscles account for the stomach's ability to expand when food enters it. The muscle fibers slide over one another, reducing the thickness of the wall while increasing its area. When empty, the stomach has practically no cavity at all, since its walls are pressed tightly together; when full it holds about 1.4 liters.

The stomach muscles perform another function. When food enters the stomach, they contract in rhythm and their combined action sends a series of wavelike contractions from the upper end of the stomach to the lower end. These contractions, known as peristalsis, mix the partially digested food with the stomach secretions and ingested liquid until it has the consistency of a thick soup; the contractions then push it gradually by small aliquots into the small intestine.

The stomach is usually emptied of its digested contents in 1 to 4 hours; the time may be longer, however, depending on the amount and type of food eaten. Foods rich in carbohydrates leave it more rapidly than proteins, and proteins more rapidly than fats. The stomach may continue to contract after it is empty; such contractions stimulate nerves in its wall and may cause hunger pangs.

The mucous membrane lining the stomach contains innumerable gastric glands; their secretion, gastric juice, contains enzymes, mucin, and hydrochloric acid. Enzymes help to split the food molecules into smaller parts during digestion. The physiologic action of mucin is not fully understood. Hydrochloric acid aids in dissolving the food before the enzymes begin working on it.

The diagnosis and treatment of stomach disorders has changed markedly with the development of endoscopy. This benign procedure permits direct examination and biopsy of the stomach and has sharply increased the accuracy of diagnosis and, as a result, the effectiveness of medical therapy. In addition, the development of whole new families of medications that reduce gastric acid secretion (such as cimetidine) and increase gastric motility (such as metoclopramide) have decreased the need for surgery for peptic ulcer disease.

Surgery of the stomach has become increasingly conservative with a better understanding of that organ's physiology. Instead of the resections that were once done routinely for peptic ulcer disease, sophisticated procedures, such as the supraselective vagotomy, that can decrease acid secretion without resection of the stomach are available. Even so, resection may still be needed for more severe cases of ulcer disease, for such complex entities as Zollinger-Ellison syndrome, and for malignancies.
Anatomy of the stomach. From Ignatavicius and Workman, 2002.
cascade stomach an atypical form of hourglass stomach, characterized radiologically by a drawing up of the posterior wall; an opaque medium first fills the upper sac and then cascades into the lower sac.
hourglass stomach one shaped somewhat like an hourglass.
leather bottle stomach linitis plastica.
stomach pump an apparatus used to remove material from the stomach, consisting of a stomach tube to which a bulb syringe is attached. The tube is inserted into the mouth or nose and passed down the esophagus into the stomach. Suction from the syringe brings the contents of the stomach up through the tube. This can be used either to remove material from the stomach in an emergency (such as when a person has swallowed poison) or to obtain a specimen for chemical analysis (such as in diagnosis of peptic ulcer or other stomach disorders).
stomach tube a flexible tube used for introducing food, medication, or other material directly into the stomach. It can be passed into the stomach by way of either the nose or the mouth. See also tube feeding. Called also esophageal tube.


(gas'tĕr), [TA]
1. Synonym(s): stomach
2. Prominent part of wasp or ant abdomen, separated from the other body parts by a thin connecting segment.
[G. gastēr, belly]


/gas·ter/ (gas´ter) [Gr.] stomach.


(stŭm'ăk) [TA]
A large, irregularly piriform sac between the esophagus and the small intestine, lying just beneath the diaphragm. Its wall has four coats or tunics: mucous, submucous, muscular, and peritoneal; the muscular coat is composed of three layers, the fibers running longitudinally in the outer, circularly in the middle, and obliquely in the inner layer.
Synonym(s): gaster [TA] , ventriculus (1) .
[G. stomachos, L. stomachus]


[Gr.] see stomach.

Patient discussion about gaster

Q. Stomach ulcer or bad heartburn? hi. i am not sure if this is just heartburn or maybe i have an ulcer. for the last 7 months i have been getting really severe pains in my stomach (between my chest and my belly button). my upper back gets sharp pains and my stomach bloats out like I’m 8 months pregnant!!!. i have tried to take antacids for this but nothing works. i don’t know what else to do. it scares me sometimes because i have no idea what it is. My mom thinks it could be an ulcer. the pain lasts for a good 4 to 5 hours and i cant even sit down because the pain hurts so bad. can anyone tell me what this might be?????

A. After 7 months with an ulcer you’d be vomiting blood and may have blood in your feces. Anti acid would have helped. So what you say doesn’t sound anything like it. I think a good idea will be going the next morning to see a Dr. – looking for a diagnosis on the web is not a very good idea. And even if you know for certain that you have an ulcer- it is curable. Why wait 7 months?

Q. 10 weeks pregnant, stomach pain. My sister is 10 weeks pregnant and she is suffering from stomach pain from week 5 until now. I am Just wondering is it normal to have stomach pain when pregnant? and dose it go away after 12 weeks? This is her first pregnancy so please educate us.

A. wife also felt pain during those weeks (5th..? maybe 4th...? up to the 11th- not sure) but it was not constant and not very painful. she went to her gyno who checked her out and told her it's the uterus stretching but it's good that she comes to check it out cause who knows.. don't take a chance.

Q. Ive been having problems with my stomach bloating and it is very tender and sore what could it be?

A. It could be many things, depending on other symptoms you may have. Is the pain relieved by eating and appears again several hours later? If so, it might be related to peptic ulcer disease (see:

Is the pain relieved by defecation? Do you have also diarrhea or constipation? If so, these features may suggest IBS (

Anyway, stomach problems can also result from serious, albeit usually rare, conditions, so consulting a doctor may be wise in this situation.

Take care,

More discussions about gaster
References in periodicals archive ?
Another version of this same story and a related story appear in a Jewish text translated by Moses Gaster.
OWEN GASTER, a favourite of Kylie Minogue, sells at exclusive boutiques where his trousers start at around pounds 270 and jackets start at pounds 400.
1 mm; head black, except mandibles testaceous; antenna testaceous; mesosoma black; gaster brown; legs testaceous.
Head black, except mandibles testaceous and clypeus ferruginous; antennae testaceous; mesosoma black, except distal apex of propodeum reddish; petiole black; gaster ferruginous; legs testaceous.
Head black, except mandibles, clypeus and part of genae near antennal toruli testaceous-whitish; antennae brown; mesosoma black; gaster brown; legs testaceous, except mid coxae basally black and hind coxae almost totally black.
Tomorrow, Owen Gaster launches his first capsule collection for Bhs, which will be mixed in with his own sharply-tailored, favoured by likes of Kylie Minogue.
Claire's parents have no problem about her touring, as managers Barry Gaster and Jackie Johnson will be acting as chaperones.
To set-up in-person or phone interviews, contact Jenni Gaster Sopko at 312-691-6201.
xyloni, with bicolored major workers having a lighter, brown-reddish head and mesosoma, and uniformly dark gaster lacking light reddish or brown areas, in a pattern very similar to that of U.
I've got some great Dolce e Gabbana clothes, and I also like Owen Gaster.
its Business Continuity Assurance Plan and the live test on Friday, August 11, 2006 contact, Bruce Gaster at 561-547-1207 and or http://www.