File:A manual of human physiology, including histology and microscopical anatomy, with special reference to the requirements of practical medicine (1885) (14594747718).jpg

Identifier: manualofhumanphy01land (find matches)
Title: A manual of human physiology, including histology and microscopical anatomy, with special reference to the requirements of practical medicine
Year: 1885 (1880s)
Authors: Landois, L. (Leonard), 1837-1902 Stirling, William, 1851-1932
Subjects: Physiology Histology
Publisher: Philadelphia, P. Blakiston, Son, and Company
Contributing Library: MBLWHOI Library
Digitizing Sponsor: MBLWHOI Library

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
r,so that while^diminished tension favours the production of the dicroticwave, it acts in the opposite way with reference to the elasticelevations. ,- ((3.) In diseases of the arterial walls affecting theirelasticity, these elevations are either greatly diminished or entirelyabolished. (4.) The farther the arteries are distant from the heart,the higher are their elevations. (5.) When the mean pressure withinthe arteries is increased by preventing the outflow of blood fromthem, the elastic vibrations are higher and nearer the apex of thecurve. (6.) They vary in number and length in the pulse-curvesobtained from different arteries of the body. When the arm is held in an upright position, after rive minutes the blood-vesselsempty themselves, and collapse, while the elasticity of the arteries is diminished. 69. Dicrotic Pulse. Sometimes during fever, especially when the temperature is high, a dicrotic pulsemay be felt, each pulse-beat, as it were, being composed of two beats (Fig. 58, X),
Text Appearing After Image:
Fig. 59.Pulsus dicrotus—P. caprizans; P. monocrotus. one beat being large and the other small, and more like an after-beat. Bothbeats correspond to one beat of the heart. The two beats are quite distinguishableby the touch. The phenomenon is only an exaggerated condition of what occurs CHARACTERS OF THE PULSE. 141 in a normal pulse. The sensible second beat is nothing more than the greatlyincreased dicrotic elevation, which, under ordinary conditions, is not felt by thefinger. Conditions.—The occurrence of a dicrotic pulse is favoured (1) by a shortprimary pulse-wave, as in fevers, where the heart beats rapidly; (2) by adiminished tension within the arterial system. A short systole and diminishedarterial blood-pressure are the most favourable conditions for causing a dicroticpulse. The double-beat may be felt only at certain parts of the arterial system,whilst at other parts only a single beat is felt. A favourite site is the radialartery of one or the other side, where conditions

Note About Images