arc

1. A curved line or segment of a circle. 2. Continuous luminous passage of an electric current in a gas or vacuum between two or more separated carbon or other electrodes. [L. arcus, a bow]

- auricular a., binauricular a. a line carried over the cranium from the center of one external auditory meatus to that of the other. SYN: interauricular a..

- bregmatolambdoid a. the line running along the sagittal suture from the bregma to the apex of the lambdoid suture.

- crater a. an a. of a direct current that forms a pitlike excavation at the positive pole.

- flame a. an a. between two impregnated electrodes that causes volatilization of the core with resultant flame.

- interauricular a. SYN: auricular a..

- longitudinal a. of skull the line carried over the skull in the midline from the nasion to the opisthion.

- mercury a. an electric discharge through mercury vapor between electrodes, one of which is usually mercury; provides a rich source of therapeutic ultraviolet rays; the containing tube is usually quartz; may also be glass with a fluorite window.

- nasobregmatic a. a line running through the midline of the forehead from the nasion to the bregma.

- naso- occipital a. the a. in the midline from the root of the nose to the inferior limit of the external occipital protuberance.

- pulmonary a. radiographically displayed contour of main pulmonary artery on frontal chest radiograph.

- reflex a. the route followed by nerve impulses in the production of a reflex act, from the peripheral receptor organ through the afferent nerve to the central nervous system synapse and then through the efferent nerve to the effector organ.

- Riolan a. 1. SYN: intestinal arterial arcades, under arcade. 2. SYN: marginal artery of colon. SEE ALSO: Riolan anastomosis. 3. SYN: Riolan anastomosis.

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absolute reticulocyte count; accelerating rate calorimetry; Accreditation Review Council; acquired immunodeficiency syndrome-related complex; active renin concentration; AIDS-related complex; American Red Cross; anomalous retinal correspondence; antigen reactive cell; arcuate; Arthritis Rehabilitation Center; arthrogryposis-renal dysfunction-cholestasis [syndrome]; Association for Retarded Children; Association for Retarded Citizens; atypical reparative changes; automatic exposure control

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ARC abbr

1) AIDS-related complex

2) American Red Cross

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AIDS-related complex: see AIDS.

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AIDS-related complex; American Red Cross; anomalous retinal correspondence.