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blood

(Encyclopedia)blood, fluid pumped by the heart that circulates throughout the body via the arteries, veins, and capillaries (see circulatory system; heart). An adult male of average size normally has about 6 quarts...

dragon's blood

(Encyclopedia)dragon's blood, name for a red resin obtained from a number of different plants. It was held by early Greeks, Romans, and Arabs to have medicinal properties; Dioscorides and other early writers descri...

blood bank

(Encyclopedia)blood bank, site or mobile unit for collecting, processing, typing, and storing whole blood, blood plasma and other blood constituents. Most hospitals maintain their own blood reserves, and the Americ...

blood clotting

(Encyclopedia)blood clotting, process by which the blood coagulates to form solid masses, or clots. In minor injuries, small oval bodies called platelets, or thrombocytes, tend to collect and form plugs in blood ve...

blood count

(Encyclopedia)blood count, method for determining the number of red (erythrocytes) and white (leukocytes) blood cells in a certain volume of blood. This test can be used as a preliminary step in diagnosing some dis...

blood groups

(Encyclopedia)blood groups, differentiation of blood by type, classified according to immunological (antigenic) properties, which are determined by specific substances on the surface of red blood cells. Blood group...

blood pressure

(Encyclopedia)blood pressure, force exerted by the blood upon the walls of the arteries. The pressure in the arteries originates in the pumping action of the heart, and pressure waves can be felt at the wrist and a...

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