Human physiology . ve Yanases observa-tions on the intestinal movements of embryo rabbits and thehuman foetus in premature abortion. He found that the period 1 In all curves recorded by Bayliss and Starling with the balloon method,contraction causes an upward movement of the lever. In the curves obtained bymeans of the enterograph, contraction is signified by a ilownicurd to be read from left to right.—TRANSLATOR. iv DIGESTION IN THE INTESTINE 243 at which the first intestinal movements appeared, both in theguinea-pig (26-27th day) and in man (77th day), is always laterthan the
Human physiology . ve Yanases observa-tions on the intestinal movements of embryo rabbits and thehuman foetus in premature abortion. He found that the period 1 In all curves recorded by Bayliss and Starling with the balloon method,contraction causes an upward movement of the lever. In the curves obtained bymeans of the enterograph, contraction is signified by a ilownicurd to be read from left to right.—TRANSLATOR. iv DIGESTION IN THE INTESTINE 243 at which the first intestinal movements appeared, both in theguinea-pig (26-27th day) and in man (77th day), is always laterthan the appearance of nerve cells and nerve fibrils in themuscular coat; hence he upholds the neurogenic interpretation ofthe intestinal movements. The peristaltic movements are true co-ordinated reflex acts,which depend on the mechanical (and chemical ?) stimuli operatingin the intestine. They are propagated by the local nervousmechanisms (Auerbachs plexus), independent of the central orextra-intestinal nervous FIG. 81.—To show rate of propagated contractions. (Bayliss and Starling.) Two balloons 10 in a loop of intestine, cut at both ends. Uli = upper and LB = lower balloon. Timemarking = 6 seconds. Rate of propagation = 5 cm. per second, as shown by the delay in thesystoles 1, 2, 3, 4, 5, of the lower in respect of the upper tracing-. (Ascending direction ofarrows shows direction of contraction.) According to Bayliss and Starling, the production of thetrue peristaltic wave is dependent on the unvarying response ofthe intestinal nervous mechanism to local stimulation. Theyformulated the law of the intestine (which might better betermed law of intestinal peristalsis) as follows: Localstimulation of the gut produces excitation above and inhibitionbelow the excited spot. This confirms the observations of Colinand van Braam-Houckgeest, from simple inspection, to the effectthat intestinal peristalsis always consists in a ring of constric-tion preceded by a wave of r
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectphysiology, bookyear1
