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aneurysm

(Encyclopedia)aneurysm ănˈyo͝orĭzəm [key], localized dilatation of a blood vessel, particularly an artery, or the heart. Dilatation of an artery, and therefore weakness of that portion of the arterial wall, ma...

buffer

(Encyclopedia)buffer, solution that can keep its relative acidity or alkalinity constant, i.e., keep its pH constant, despite the addition of strong acids or strong bases. Buffer solutions are frequently solutions ...

schistosomiasis

(Encyclopedia)schistosomiasis bĭlˌhärzīˈəsĭs [key], or snail fever, parasitic disease caused by blood flukes, trematode worms of the genus Schistosoma. Three species are human parasites: S. mansoni, S. japon...

inflammation

(Encyclopedia)inflammation, reaction of the body to injury or to infectious, allergic, or chemical irritation. The symptoms are redness, swelling, heat, and pain resulting from dilation of the blood vessels in the ...

ruby

(Encyclopedia)ruby, precious stone, the transparent red variety of corundum, found chiefly in Myanmar, Thailand, and Sri Lanka and classified among the most valuable of gems. The Myanmarese stones are blood red, th...

scalp

(Encyclopedia)scalp, the integument covering the top of the head. It consists of three layers of tissue: the skin, an underlying layer of tissue and blood vessels, and the occipitofrontalis muscle stretching from t...

infarction

(Encyclopedia)infarction, 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. The acute emerg...

respiration

(Encyclopedia)CE5 Respiratory system respiration, process by which an organism exchanges gases with its environment. The term now refers to the overall process by which oxygen is abstracted from air and is tran...

autoimmune disease

(Encyclopedia)autoimmune disease, any of a number of abnormal conditions caused when the body produces antibodies to its own substances. In rheumatoid arthritis, a group of antibody molecules called collectively RF...

urinalysis

(Encyclopedia)urinalysis yo͝orˌənălˈĭsĭs [key], clinical examination of urine for the purpose of medical diagnosis. Urine is initially examined for such characteristics as color, odor, and specific gravity. ...