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urinary system

(Encyclopedia)CE5 Urinary system urinary system, group of organs of the body concerned with excretion of urine, that is, water and the waste products of metabolism. In humans, the kidneys are two small organs s...

thrombolytic drug

(Encyclopedia)thrombolytic drug thrŏmˌbəlĭtˈĭk [key] or clot-dissolving drug, substance, such as streptokinase or tissue plasminogen activator (tPA), that causes the breakdown of blood clots (see thrombosis) ...

liver

(Encyclopedia)liver, largest glandular organ of the body, weighing about 3 lb (1.36 kg). It is reddish brown in color and is divided into four lobes of unequal size and shape. The liver lies on the right side of th...

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...

Furies

(Encyclopedia)Furies or Erinyes ērĭnˈē-ēz [key], in Greek and Roman religion and mythology, three daughters of Mother Earth, conceived from the blood of Uranus, when Kronos castrated him. They were powerful di...

calcium-channel blocker

(Encyclopedia)calcium-channel blocker, any of a class of drugs used in treating hypertension, angina pectoris, and certain arrhythmias. They prevent the calcium ions needed for muscle contraction from entering the ...

anticoagulant

(Encyclopedia)anticoagulant ănˌtēkōăgˈyələnt [key], any of several substances that inhibit blood clot formation (see blood clotting). Some anticoagulants, such as the coumarin derivatives bishydroxycoumarin...

aorta

(Encyclopedia)CE5 Aorta aorta āôrˈtə [key], primary artery of the circulatory system in mammals, delivering oxygenated blood to all other arteries except those of the lungs. The human aorta, c.1 in. (2.54 c...

pulse, in anatomy

(Encyclopedia)pulse, alternate expansion and contraction of artery walls as heart action varies blood volume within the arteries. Artery walls are elastic. Hence they become distended by increased blood volume duri...

hemoglobin

(Encyclopedia)hemoglobin hēˈməglōˌbĭn [key], respiratory protein found in the red blood cells (erythrocytes) of all vertebrates and some invertebrates. A hemoglobin molecule is composed of a protein group, kn...