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Related to duodenum: pancreas, duodenitis


see intestineintestine,
muscular hoselike portion of the gastrointestinal tract extending from the lower end of the stomach (pylorus) to the anal opening. In humans this fairly narrow (about 1 in./2.
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; pancreaspancreas
, glandular organ that secretes digestive enzymes and hormones. In humans, the pancreas is a yellowish organ about 7 in. (17.8 cm) long and 1.5 in. (3.8 cm) wide. It lies beneath the stomach and is connected to the small intestine at the duodenum (see digestive system).
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The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved. www.cc.columbia.edu/cu/cup/
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



the first section (individually distinct in man, mammals, and birds) of the small intestine, from the pylorus to the jejunum.

The length of the duodenum in man is approximately 25–30 cm (the width of about 12 fingers—hence the name); its volume is 150–250 ml. The wall of the duodenum consists of three layers: the inner layer of mucous membrane, the middle layer of muscular membrane, and the external layer of serous membrane. The mucous membrane forms numerous transverse folds, its surface studded with villi; it contains cells that manufacture an intestinal juice containing enzymes that break down proteins, fats, and carbohydrates; it also contains enterokinase, which converts trypsinogen, the inactive enzyme of pancreatic juice, to the active trypsin. In the wall of the upper portion of the duodenum are the so-called Brun-ner’s glands, which, in structure and in the composition of the juice they secrete, are closely related to the glands of the pyloric portion of the stomach. The effluent ducts of the pancreas and liver open into the duodenal cavity through a common aperture. The acidic, gruel-like food mass (chyme) passing from the stomach continues to be digested in the duodenum under the influence of enzymes of the alkaline pancreatic and intestinal juices. Proteins are broken down into amino acids, carbohydrates into monosaccharides, and fats into glycerol and fatty acids. Bile promotes the digestion and absorption of fats. Through the walls of the villi the products of proteolysis and glycolysis enter the blood; the products of lypolysis enter the lymph. In the walls of the duodenum an inactive substance is formed (prosecretin) which, under the action of hydrochloric acid entering from the stomach, is converted to the biologically active secretin. Upon entering the blood secretin, acting along with the sympathetic nervous system, stimulates the secretion of pancreatic juice. Ulcer is the most common disease of the duodenum.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


[dü′äd·ən·əm or dü·ə′dē·nəm]
The first section of the small intestine of mammals, extending from the pylorus to the jejunum.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


the first part of the small intestine, between the stomach and the jejunum
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
References in periodicals archive ?
He said he was also told that if the duodenum was already torn a postmortem examination could have fully split it.
Brunner gland cysts are very rare polypoid or nodular lesions of the duodenum characterized by a submucosal cystic dilation of the Brunner gland ducts.
Thus, we performed upper endoscopy, and the polyp was resected from the fourth part of the duodenum.
This results supported by Bartell and Batal [11] and Soltan [9], who observed that consumption of 1.0% Gln in broilers, resulted in longer villi height and higher relative weights of duodenum and jejunum, and consequently higher BWG.
Firstly, it produces digestive juices which pass through the pancreatic duct into the duodenum. These contain enzymes that break down protein, fats and carbohydrates in your food.
Abdominal contrast-enhanced computed tomography (CT) showed a tumor (1.8 cm x 1.8 cm) in the posterior wall of the stomach and another mass (3.9 cm x 3.4 cm) in the descending part of the duodenum. The CT and endoscopic ultrasound images suggested that the lesions in both stomach and duodenum were likely to be GISTs.
On the radiograph, it was found that the stomach and the 1st and 2nd part of the duodenum were markedly enlarged, the gastric outlet was not obstructed, the horizontal part of the duodenum had an appearance compatible with SMA compression, and passage in this part was delayed.
These tumors may originate from any location in the entire gastrointestinal tract, and the most susceptible sites are the stomach (40%-60%), small intestine (30%-40%), colon and rectum (5%), and esophagus (5%), whereas only 3%-5% of GISTs occur in the duodenum (4-6).
Sites of involvement included duodenum (three cases), jejunum (one), both duodenum and jejunum (one), ileum (one), cecum (one), and stomach (one).
Despite its similarity to the general mammal small intestine microstructure, the present results indicated that the hedgehog duodenum contained fewer Brunner's glands, and that the Paneth cells were lacking in the crypt.
We are reporting a case of accidental nail ingestion in a 10-year-old child which led to a sealed perforation of duodenum. Operative management included primary duodenal repair after removal of nail.