A manual of human physiology, including histology and microscopical anatomy, with special reference to the requirements of practical medicine . surface of theauriculo-ventricular valves, whose curved margins are opposed to eachother like teeth, and are pressed hermetically against each other (Sand-borg and Worm Miiller). It is impossible for the blood to push thecusps backwards into the auricle, as the chordce tendinice hold fast theirmargins and surfaces like a taut sail. The margins of the neighbouring cusps are also kept in apposition by thechordre tendinise from one papillary musclealways
A manual of human physiology, including histology and microscopical anatomy, with special reference to the requirements of practical medicine . surface of theauriculo-ventricular valves, whose curved margins are opposed to eachother like teeth, and are pressed hermetically against each other (Sand-borg and Worm Miiller). It is impossible for the blood to push thecusps backwards into the auricle, as the chordce tendinice hold fast theirmargins and surfaces like a taut sail. The margins of the neighbouring cusps are also kept in apposition by thechordre tendinise from one papillary musclealways passing to the adjoining edges oftwo cusps (John Eeid). The extent towhich the ventricular wall is shortened iscompensated by the contraction of thepapillary muscle, and also of the largemuscular chordte, so that the cusps cannotbe pushed into the auricle. 24 When the valves are closed their surfaces The closed semi-lunar are horizontal, so that even when thevalves of the pulmonary ventricles are contracted to their greatestartery seen from below. extentj ft gmall amount of Uood remains, which is not expelled (Sandborg and Worm Miiller).. PATHOLOGICAL DISTURBANCES OF CARDIAC ACTION. 79 (3.) Opening of the Semi-lunar Valves.—When the pressure withinthe ventricle exceeds that in the arteries, the semi-lunar valves areforced open and stretched like a sail across the pocket-like sinus,without, however, being firmly or directly applied to the wall of thearteries (pulmonary and aorta), and thus the blood enters the arteries. Negative Pressure in the Ventricle.—Goltz and Gaule found that there wasa negative pressure of 235 mm. Hg. (dog) in the interior of the ventricle during acertain phase of the hearts action. They surmised that that phase coincided withthe diastolic dilatation, for which they assumed a considerable power of observed a similar condition and called it vacuite postsystolique, butthought that it coincided with the end of the systole; while Moens is
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectphysiology, bookyear1
