A manual of practical medical electricity - the Röntgen rays and Finsen light (1902) (14597172927)

Identifier: manualofpractica00turn (find matches)

Title: A manual of practical medical electricity : the Röntgen rays and Finsen light

Year: 1902 (1900s)

Authors: Turner, Dawson

Subjects: X-Rays Electrophysiology Electrosurgery Electric Stimulation Therapy Electrotherapeutics X-rays Electrophysiology Electrosurgery

Publisher: New York : William Wood & Company

Contributing Library: Francis A. Countway Library of Medicine

Digitizing Sponsor: Open Knowledge Commons and Harvard Medical School

Text Appearing Before Image:

e regularlydecreased in amplitude so long as the current was main-tained in one direction, but that they could be restoredto their original vigour by reversing the direction. Werethe diminution in the amplitude of the contractions duemerely to fatigue, rest should suffice to restore them ; butthis it does not do. These facts support the view that,during the passage of a current, chemical changes occurin the interior of the muscle ; that these are of the natureof polarization changes, which are increased by the passage-of the original current, and which can be swept away andnullified by a reversal of the current. Let a current of two or three milliamperes be passed fora few minutes through the leg-muscles of a healthyuninjured frog. A week later examine the contractionsof these muscles, and they will be found to have lost agreat part of their excitability, not only for currents inthe same direction as the previous one, but also for those 12 178 A Manual of Practical Medical Electricity

Text Appearing After Image:

Electro-Physiology 179 in the opposite direction. The muscles of the leg whichwas not electrolyzed will contract very much better. But the microscope can also be used. Submit a frogtwo or three times to a continuous current, and thenpermit it to live ; a month later examine its muscles :they will be found to exhibit marked microscopicalchanges. M. Weiss has found that a single five minutesseance with a current-strength of one to two milliamperesso alters the muscular structure that evidences of it canbe seen for several days afterwards. (Weiss, Electro-physiologic, p. 127.) It may fairly be held to be probable that the strongcurrents (200 m.a.) passed by Apostoli through uterinefibroids exercise the same effect, and that their diminutionin size is at any rate partly due to the retrogressive anddisintegrating changes set up in them by interpolarchemical changes. Evidence of the electrolytic action ofa continuous current upon the tissues is to be found inthe circumstance that the body w

a manual of practical medical electricity book illustrations medicine medical illustrations medical history history of technology electric power electricity x ray röntgen medical therapy electrotherapeutics images from internet archive

1902

Open Knowledge Commons and Harvard Medical School

http://commons.wikimedia.org/

public domain