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expert system

A computer program using a set of rules that analyzes information and simulates the judgment and behavior of a specialist in a particular field to provide analysis and to possibly recommend a course of action.


(ĕks″pĭ-rā′shŭn) [Gr. ex, out, + L. spirare, to breathe] 1. Expulsion of air from the lungs in breathing. Normally the ratio of the duration of inspiration to expiration is 1:3. Exhalation takes longer than inspiration because exhalation occurs passively. SEE: diaphragm for illus.; inspiration; respiration. 2. Death.

active e. Expiration accomplished as a result of muscular activity, as in forced respiration. The muscles used in forced expiration are those of the abdominal wall (external and internal oblique, rectus, and transversus abdominis), the internal intercostalis, serratus posterior inferior, platysma, and quadratus lumborum.

passive e. Expiration, performed during quiet respiration, that requires no muscular effort. It is brought about by the elasticity of the lungs, and by the ascent of the diaphragm and the weight of the descending chest wall, which compress the lungs.

expiration date

The last day on which a drug or other therapeutic agent is still considered potent.


(ĕks-pī′ră-tor″ē) Pert. to expiration of air from the lungs.

expiratory pause time

ABBR: TEP. The interval between the end of one exhalation and the beginning of the next.

expiratory positive airway pressure

SEE: under pressure.

expiratory trigger sensitivity

The adjustment of a pressure-support breath to the neurally mediated end of expiration. This machine adaptation to the patient’s respiratory efforts is a refinement of mechanical ventilation that decreases patient discomfort and the work of breathing.


(ĕk-spī′ĕr) 1. To breathe out or exhale. 2. To die.


(ĕks-plănt′) [″ + L. planta, sprout] 1. To remove a piece of living tissue from the body and transfer it to an artificial culture medium for growth, as in tissue culture. Opposite of implant. 2. To remove a donor organ for transplantation. 3. An organ removed for transplantation.


(ĕk-splĭs′ĭt) [L. explicare, to unfold, set forth] 1. Clearly and definitively stated. 2. Unequivocal.


(eks-plōd′) [L. explodere, to drive away by clapping the hands] 1. To release energy suddenly, as when a bomb detonates. 2. In epidemiology, to appear suddenly or have rapid onset. 3. To display a powerful emotion in words or deeds.


[L. explorare, to search out] Examination of an organ or part ...

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