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hepatitis

(Encyclopedia)hepatitis hĕpˌətīˈtĭs [key], inflammation of the liver. There are many types of hepatitis. Causes include viruses, toxic chemicals, alcohol consumption, parasites and bacteria, and certain drugs...

herpes simplex

(Encyclopedia)herpes simplex hûrˈpēz [key], an acute viral infection of the skin characterized by one or more painful, itching blisters filled with clear fluid. It is caused by either of two herpes simplex virus...

histamine

(Encyclopedia)histamine hĭsˈtəmēnˌ [key], organic compound derived in the body from the amino acid histidine by the removal of a carboxyl group (COOH). Although found in many plant and animal tissues, histamin...

hives

(Encyclopedia)hives (urticaria), rash consisting of blotches or localized swellings (wheals) of the skin, caused by an allergic reaction (see allergy). The swelling is caused by distention of the skin capillaries a...

anthrax

(Encyclopedia)anthrax ănˈthrăks [key], acute infectious disease of animals that can be secondarily transmitted to humans. It is caused by a bacterium (Bacillus anthracis) that primarily affects sheep, horses, ho...

Hong Kong

(Encyclopedia)CE5 Hong Kong hŏng kŏng [key], Mandarin Xianggang, special administrative region of China, formerly a British crown colony (2015 est. pop. 7,246,000), land area 422 sq mi (1,092 sq km), adjacent ...

housing

(Encyclopedia)housing, in general, living accommodations available for the inhabitants of a community. Throughout the 19th cent., with the advent of the Industrial Revolution, housing as a problem worsened as urban...

Huntington's disease

(Encyclopedia)Huntington's disease, hereditary, acute disturbance of the central nervous system usually beginning in middle age and characterized by involuntary muscular movements and progressive intellectual deter...

hypersensitivity

(Encyclopedia)hypersensitivity, heightened response in a body tissue to an antigen or foreign substance. The body normally responds to an antigen by producing specific antibodies against it. The antibodies impart i...

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...