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stroke,destruction of brain tissue as a result of intracerebral hemorrhage or infarctioninfarction,
blockage of blood circulation to a localized area or organ of the body resulting in tissue death. Infarctions commonly occur in the spleen, kidney, lungs, brain, and heart.
..... Click the link for more information. caused by thrombosisthrombosis
, obstruction of an artery or vein by a blood clot (thrombus). Arterial thrombosis is generally more serious because the supply of oxygen and nutrition to an area of the body is halted.
..... Click the link for more information. (clotting) or embolusembolus
, foreign matter circulating in and obstructing a blood vessel. It may be a portion of a clot that has separated from the wall of a vessel (see thrombosis), a bubble of gas or air (known as an air embolus), a globule of fat, a clump of bacterial matter, or a clump of
..... Click the link for more information. (obstruction in a blood vessel caused by clotted blood or other foreign matter circulating in the bloodstream); formerly called apoplexy. Cerebral hemorrhage or thrombosis occurs most often in elderly persons with constricted arteries (see arteriosclerosisarteriosclerosis
, general term for a condition characterized by thickening, hardening, and loss of elasticity of the walls of the blood vessels. These changes are frequently accompanied by accumulations inside the vessel walls of lipids, e.g.
..... Click the link for more information. ), although either may also be caused by inflammatory or toxic damage to the cerebral blood vessels. Cerebral embolism may occur at any age, even in children.
Symptoms of stroke develop suddenly. In cases of severe brain damage there may be deep coma, paralysis of one side of the body, and loss of speech, followed by death or permanent neurological disturbances after recovery. If the brain damage sustained has been slight, there is usually complete recovery, but most survivors of stroke require extensive rehabilitation. Hypertensionhypertension
or high blood pressure,
elevated blood pressure resulting from an increase in the amount of blood pumped by the heart or from increased resistance to the flow of blood through the small arterial blood vessels (arterioles).
..... Click the link for more information. , which is a major cause of intracranial hemorrhage and stroke, can be treated by preventive measures using diet (e.g., increasing nutrients such as antioxidants and folate), drug therapy, and stress reduction techniques. Other preventive measures for people at high risk include daily aspirin to retard clot formation and surgical correction of the narrowed carotid artery. Sometimes surgical removal of the clot is possible on larger vessels, but it is usually pointless after the stroke or when blockage is widespread. The thrombolytic drugthrombolytic drug
or clot-dissolving drug,
substance, such as streptokinase or tissue plasminogen activator (tPA), that causes the breakdown of blood clots (see thrombosis) that obstruct the flow of blood through the vessels.
..... Click the link for more information. tissue plasminogen activator, widely used to treat heart attacks, has been approved for use within three hours of the onset of strokes caused by clots.
See ASCII for other synonyms.
stroke(1) In printing, the weight, or thickness, of a character. For example, in the LaserJet, one of the specifications of the font description is the stroke weight from lightest to boldest. See stroke weight.
(2) In computer graphics, a pen or brush stroke. The stroke function lets you set the width of the line being drawn.