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circulatory system

(Encyclopedia)CE5 Circulatory system circulatory system, group of organs that transport blood and the substances it carries to and from all parts of the body. The circulatory system can be considered as compose...

bloodletting

(Encyclopedia)bloodletting, also called bleeding, practice of drawing blood from the body in the treatment of disease. General bloodletting consists of the abstraction of blood by incision into an artery (arterioto...

shock

(Encyclopedia)shock, any condition in which the circulatory system is unable to provide adequate circulation to the body tissues, also called circulatory failure or circulatory collapse. Shock results in the slowin...

polycythemia

(Encyclopedia)polycythemia pŏlˌēsīthēˈmēə [key], condition characterized by an increase in the production of red blood cells, or erythrocytes, in the blood. Primary polycythemia, also called erythremia, or ...

hemolysis

(Encyclopedia)hemolysis hĭmŏlˈĭsĭs [key], destruction of red blood cells in the bloodstream. Although new red blood cells, or erythrocytes, are continuously created and old ones destroyed, an excessive rate of...

vein

(Encyclopedia)CE5 Cross section of vein showing valves vein, blood vessel that returns blood to the heart. Except for the pulmonary vein, which carries oxygenated blood from the lungs to the heart, veins carry ...

kidney, artificial

(Encyclopedia)kidney, artificial, mechanical device capable of assuming the functions ordinarily performed by the kidneys. In treating cases of kidney failure a tube is inserted into an artery in the patient's arm ...

blister

(Encyclopedia)blister, puffy swelling of the outer skin (epidermis) caused by burn, friction, or irritants like poison ivy. A response of the body to protect deeper tissue, blisters generally contain serum, the liq...

spleen

(Encyclopedia)spleen, soft, purplish-red organ that lies under the diaphragm on the left side of the abdominal cavity. The spleen acts as a filter against foreign organisms that infect the bloodstream, and also fil...

papaverine

(Encyclopedia)papaverine pəpăvˈərēn [key], alkaloid found in opium that acts as a muscle relaxant and vasodilator. The drug relaxes the smooth muscle of the larger blood vessels and is used to increase the blo...