The special pathology and treatment of the organic diseases of the stomach : in two parts / by John C. Hemmeter.

  • Hemmeter, John C. (John Conrad), 1863-1931.
Date:
1897
Catalogue details

Licence: Public Domain Mark

Credit: The special pathology and treatment of the organic diseases of the stomach : in two parts / by John C. Hemmeter. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    so that the upper end of the jejunum can readily be distinguished from the lower part of the ileum. STRUCTURE OF THE SMALL INTESTINE. The small intestine, like the stomach, is composed of four coats, viz., the serous or peritoneal, muscular, areolar, and mucous. The external or serous coat almost entirely surrounds the intes- tinal tube in the whole extent of jejunum and ileum leaving only a narrow interval behind, where it passes off and becomes continous with the two layers of the mesentery. The line at which this takes place is named the attached or mesenteric border of the intestine. The duodenum, on the other hand, is but partially covered by the peritoneum. The muscular coat censists of two layers of fibers; an outer longitudinal, and an inner or circular set. The longitudinal fibers constitute an entire but comparatively thin layer, and are most obvious along the free border of the intestine. The circular layer is thicker and more distinct. The muscular tunic becomes gradually thinner towards the lower part of the. small intestine. It is pale in color, and is composed of plain muscular tissue, the cells of which are of considerable length. The progressive contraction of these fibers, commencing at any part of the intestine, and advancing in a downward direction, pro- duces the peculiar vermicular or peristaltic movement by which the contents are forced onwards through the canal. In the narrowing of the tube the circular fibers are mainly concerned, the longitudinal fibres tending to produce dilatation (Exner); and those found along the free border of the intestine may have the effect of straightening or unfolding its successive convolutions. There is a gangliated plex- us of nerve-fibres and a network of lymphatic vessels between the two muscular layers. The submucous coat of the small intestine is a layer of areolar tissue of a loose texture, which is connected more firmly with the mucous than with the muscular coat. Within it the blood-vessels ramify before passing to the mucous membrane, and there is a gan- gliated plexus of nerve-fibers and a network of large lymphatic vessels in it. The internal coat or mucous membrane is characterised by the finely flocculent or shaggy apearance of its inner surface resembling