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fluke

(Encyclopedia)fluke, parasitic flatworm of the trematoda class, related to the tapeworm. Instead of the cilia, external sense organs, and epidermis of the free-living flatworms, adult flukes have sucking disks with...

drug poisoning

(Encyclopedia)drug poisoning, toxic effects caused by an administered drug. Worldwide more than 9 million natural and synthetic chemicals have been identified; fewer than 3000 cause more than 95% of acidental and d...

corticosteroid drug

(Encyclopedia)corticosteroid drug kôrˌtəkōstârˈoid [key], any one of several synthetic or naturally occurring substances with the general chemical structure of steroids. They are used therapeutically to mimic...

neural network

(Encyclopedia)neural network or neural computing, computer architecture modeled upon the human brain's interconnected system of neurons. Neural networks imitate the brain's ability to sort out patterns and learn fr...

Zika virus

(Encyclopedia)Zika virus zēˈkə [key], single-stranded RNA virus of the genus flavivirus that infects human and primates and causes a disease known as Zika fever or zika. It is primarily transmitted by the bite o...

photosynthesis

(Encyclopedia)photosynthesis fōˌtōsĭnˈthəsĭs [key], process in which green plants, algae, and cyanobacteria utilize the energy of sunlight to manufacture carbohydrates from carbon dioxide and water in the pr...

public health

(Encyclopedia)public health, field of medicine and hygiene dealing with the prevention of disease and the promotion of health by government agencies. In the United States, public health authorities are engaged in m...

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...

Alzheimer's disease

(Encyclopedia)Alzheimer's disease ălsˈhīˌmərz, ôls– [key], degenerative disease of nerve cells in the cerebral cortex that leads to atrophy of the brain and senile dementia and, ultimately, death. The disea...

teeth

(Encyclopedia)CE5 A. Upper and lower teeth of an adult B. Cross section of a molar teeth, hard, calcified structures embedded in the bone of the jaws of vertebrates that perform the primary function of masticat...