position effect

effect /ef·fect/ (ĕ-fekt´) the result produced by an action.

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Anrep effect  abrupt elevation of aortic pressure results in a positive inotropic effect, augmented resistance to outflow in the heart.

Bayliss effect  increased perfusion pressure and subsequent stretch of vascular smooth muscle causes muscle contraction and increased resistance, which returns blood flow to normal in spite of the elevated perfusion pressure.

Bohr effect  increase of carbon dioxide in blood causes decreased affinity of hemoglobin for oxygen.

Doppler effect  the relationship of the apparent frequency of waves, as of sound, light, and radio waves, to the relative motion of the source of the waves and the observer, the frequency increasing as the two approach each other and decreasing as they move apart.

experimenter effects  demand characteristics.

Haldane effect  increased oxygenation of hemoglobin promotes dissociation of carbon dioxide.

position effect  in genetics, the changed effect produced by alteration of the relative positions of various genes on the chromosomes.

pressure effect  the sum of the changes that are due to obstruction of tissue drainage by pressure.

side effect  a consequence other than that for which an agent is used, especially an adverse effect on another organ system.

Somogyi effect  a rebound phenomenon occurring in diabetes: overtreatment with insulin induces hypoglycemia, which initiates the release of epinephrine, ACTH, glucagon, and growth hormone, which stimulate lipolysis, gluconeogenesis, and glycogenolysis, which, in turn, result in a rebound hyperglycemia and ketosis.

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position effect

n.

Variation in the expression of a gene that results from changes in the gene's position along a chromosome.

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effect

a result produced by an action. The relationship between the two can be expressed in linear form. The total association between them may be the sum of a number of effects. The effect may be direct when it is exerted without being transmitted through intervening factors, or indirect when it is. It may also be a spurious effect when the observed changes are due to causes and correlations common to both.

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additive effect

the combined effect produced by the action of two or more agents, being equal to the sum of their separate effects.

Coolidge effect

the stimulation of sexual behavior in a male animal upon exposure to a new female.

cumulative effect

cumulation action.

experimenter e's

demand characteristics; the characteristics supplied by the experimental subject in response to what it perceives are the demands of the experimenter.

effect modifier

a factor which modifies the effect of a causal factor under study. Called also interaction.

position effect

in genetics, the changed effect produced by alteration of the relative positions of various genes on the chromosomes.

pressure effect

the sum of the changes that are due to obstruction of tissue drainage by pressure.

side effect

a consequence other than that for which an agent is used, especially an adverse effect on another organ system.