The Mechanics Of The Digestive Tract

Author : Walter C. Alvarez
Publisher :
ISBN 13 : 9781332238712
Total Pages : 208 pages
Book Rating : 4.2/5 (387 download)

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Download or read book The Mechanics of the Digestive Tract (Classic Reprint) written by Walter C. Alvarez and published by . This book was released on 2015-08-05 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from The Mechanics of the Digestive Tract In 1913, while doing some work on the absorption of gases injected into loops of intestine, I noticed differences in irritability in different parts of the bowel; that is, the jejunum reacted actively to distention, while the ileum generally responded but little. It promptly occurred to me that this graded difference in irritability might account for the downward progress of food in the bowel, because it seemed reasonable to suppose that material would have to move from the more irritable and active regions to the less irritable and active ones. While attempting to show these differences in irritability with excised segments of intestine, I found that the rate of rhythmic contraction of the muscle is graded downwards from the pylorus to the ileocecal sphincter. Remembering how much the heart specialist has profited by the careful study of conduction along a similar rhythmic gradient from the sinus node to the ventricle, I was filled with the hope that a careful analysis of the gradient found in the bowel might throw light on the mechanism of peristalsis and might put more system into the science of gastro-enterology. As time goes on that hope seems more and more likely to be realized. During 1915, gradients of rhythmicity, irritability and latent period were found in the stomach; and a sort of pacemaker was located on the lesser curvature near the cardia. Later, my assistants and I showed that in addition to the rhythmic gradients in the stomach and intestine, and probably underlying them, there are gradients in metabolism. Ways were found in which these chemical gradients can theoretically be upset; and actually they were found upset in many of the sickly or distempered animals studied. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.