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pacemaker, artificial

(Encyclopedia)pacemaker, artificial, device used to stimulate a rhythmic heartbeat by means of electrical impulses. Implanted in the body when the heart's own electrical conduction system (natural pacemaker) does n...

Kantrowitz, Adrian

(Encyclopedia)Kantrowitz, Adrian kănˈtrəwĭtsˌ [key], 1918–2008, American surgeon, b. New York City, grad. New York Univ. (1940). The son of a physician, Kantrowitz received his M.D. from the Long Island Coll...

heart, in anatomy

(Encyclopedia) CE5 Cross section of heart, with arrows indicating direction of blood flow heart, muscular organ that pumps blood to all parts of the body. The rhythmic beating of the heart is a ceaseless activit...

arrhythmia

(Encyclopedia)arrhythmia ārĭᵺˈmēə [key], disturbance in the rate or rhythm of the heartbeat. Various arrhythmias can be symptoms of serious heart disorders; however, they are usually of no medical significan...

artificial limb

(Encyclopedia)artificial limb, mechanical replacement for a missing limb. An artificial limb, called a prosthesis, must be light and flexible to permit easy movement, but must also be sufficiently sturdy to support...

plutonium

(Encyclopedia)plutonium plo͞otōˈnēəm [key], radioactive chemical element; symbol Pu; at. no. 94; mass no. of most stable isotope 244; m.p. 641℃; b.p. 3,232℃; sp. gr. 19.84 at 20℃; valence +3, +4, +5, or ...

defibrillator

(Encyclopedia)defibrillator, device that delivers an electrical shock to the heart in order to stop certain forms of rapid heart rhythm disturbances (arrhythmias). The shock changes a fibrillation to an organized r...
 

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