target lesion

lesion

any pathological or traumatic discontinuity of tissue or loss of function of a part. Lesion is a broad term, including wounds, sores, ulcers, tumors, cataracts and any other tissue damage. They range from the skin sores associated with eczema to the changes in lung tissue that occur in tuberculosis.

Terms describing distribution of lesions. By permission from Slauson DO, Cooper BJ, Mechanisms of Disease: A Textbook of Comparative General Pathology, Mosby, 2001

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target lesion

see target lesion.

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target

1. an object or area toward which something is directed, e.g. target animal, population, level or nucleotide sequence.

2. the area of the anode of an x-ray tube where the electron beam collides causing the emission of x-rays.

3. a cell or organ that is affected by a particular agent, e.g. a hormone or drug.

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target cell

see target cell.

target-film distance

the distance from the target of the x-ray tube and the plane of the x-ray film.

target lesion

skin lesion consisting of annular or arciform areas of erythema with central pigmentation. Associated with bacterial hypersensitivity and seborrheic dermatitis. Called also bull's eye lesion.

performance target

in herd health programs target performances are set up in a number of production and health functions in order to provide an incentive and give some measure of performance other than an absolute one. This enables farmers to be rated on their effective performance in spite of the great variations that can occur between them in basic resources.

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target lesion

Dermatology A lesion typical of erythema multiforme–EM in which a vesicle is surrounded by an often hemorrhagic maculopapule; EM is often self-limited, of acute onset, resolves in 3-6 wks, and has a cyclical pattern; EM lesions are 'multiform' and include macules, papules, vesicles, bullae Etiology Idiopathic or follow infections, drug therapy or occur in immunocompromised hosts