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athlete's foot

(ath′lēts″) SEE: under foot.

athletic trainer

(ath-let′ik) A person who has completed educational and clinical experiences and is capable of working with athletes and others involved in strenuous physical activity and their environment to help prevent injuries, advise them concerning appropriate equipment, clinically diagnose injuries, administer emergency treatment, determine if specialized medical care is required, and rehabilitate those with injuries. Athletic trainers work under the direction of licensed physicians. In most states, athletic trainers must be licensed to practice.


Angiotensin II.


(at′ĭ-van″) SEE: lorazepam.

Atlanta Classification of Acute Pancreatitis

A clinical risk stratification tool to gauge the severity of disease in patients with acute pancreatitis. It consists of measurements of the patient's blood pressure, serum creatinine level, and oxygenation. These are combined with evidence of hemorrhage, abscess formation, pseudocyst formation, or necrosis along with Ranson criteria, C-reactive protein levels, and APACHE-III scores.


(ăt-lant′ăl) [atlanto- + -al] Pert. to the atlas.


[Gr. atlas, stem atlant-, Atlas] A prefix meaning the atlas.


(ăt-lant″ō-ak′sē-ăl) [atlanto- + axial] Pert. to the atlas and the axis.

atlanto-occipital, atlantooccipital

(ăt-lan″tō-ok-sip′tĭ-ăl) [atlanto- + occipital] Pert. to the atlas and the occipital bones.


(at′lăs) [In Gr. mythology a Titan condemned to support the heavens on his shoulders] 1. The first cervical vertebra by which the spine articulates with the occipital bone of the head. 2. A comprehensive map, e.g., of an anatomical structure, an organ, or a tissue.


advanced trauma life support.


atmosphere; atmosphere, standard.


(at′mŏs-fēr″) [Gr. atmos, vapor + sphere] 1. The gases surrounding the earth. 2. Climatic condition of a locality. 3. In physics, the pressure of the air on the earth at mean sea level, approx. 14.7 lb/sq in (101, 325 pascals or 760 torr). 4. In chemistry, any gaseous medium around a body. atmospheric (at″mŏs-fēr′ik), adj.

standard a. The pressure of air at sea level when the temperature is 0°C (32°F). This is equal to 14.7 lb/sq in., or 760 torr, or 101, 325 pascals.

atmospheric temperature and pressure, saturated

ABBR: ATPS. Ambient temperature and pressure, saturated.


acute tubular necrosis.


asymmetrical tonic neck reflex.



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