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ambulatory surgery center.


(as″kă-rī′ă-sĭs) [ascaris + -asis] Infestation by Ascaris lumbricoides.


(as′kă-rĭd) [ascar(is) + -id(ae)] A nematode worm of the family Ascaridae. ascarid, adj.


(as′kă-rĭs) [Gr. askaris, pinworm] A genus of worms belonging to the family Ascaridae. They inhabit the intestines of vertebrates.

A. lumbricoides A species of Ascaris that lives in the human intestine; adults may grow to 12 in long. Eggs are passed with the feces and require at least 2 weeks' incubation in the soil before they become infective. After being swallowed, the eggs hatch in the intestinal tract, and the larvae enter the venous circulation and pass to the lungs. From there they migrate up the respiratory passages, are swallowed, and reach their site of continued residence, the jejunum. In a 1- to 2-year life span, the female is capable of producing 200, 000 eggs a day. The eggs are passed with the feces, and a new cycle is started. Children up to the ages of 12 to 14 are likely to be infected. Intestinal obstruction may be a complication in children under 6 years of age.

 TREATMENT: Albendazole and mebendazole are the drugs most commonly used to treat infection with Ascaris.


(ă-skar′ĭ-dēz″) pl. ascarides A worm of the genus Ascaris.

raccoon a. Baylisascaris procyonis.


(ă-send′) [L. ascendere, to climb up] To move from the lower part of the body toward the head. Guillain-Barré syndrome is an example of an ascending paralysis, beginning in the feet and progressing upward to the muscles of the legs, abdomen, and chest.

ascertainment bias

Sampling bias.


An abbreviation for atypical squamous cells. The finding cannot exclude a high-grade squamous intraepithelial lesion, an abnormal finding on a Papanicolaou smear in which a high-grade (precancerous or cancerous) lesion is suspected but not definitively identified cytologically. Patients with ASC-H cell findings are referred for colposcopy.

Aschoff, Ludwig

(ash′of″) German pathologist, 1866–1942.

A. body One of microscopic foci of fibrinoid degeneration and granulomatous inflammation found in the interstitial tissues of the heart in rheumatic fever.

A.'s cell A large cell with basophilic cytoplasm and a large vesicular nucleus, often multinucleated.


(as′(k)ī″, (k)ē″) Pl. of ascus.


(as′(k)ē-ă) [L. ascia, ax] A form of spiral bandage with each turn overlapping the previous one for a third of its width.

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