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1. position; posterior; postpartum; pressure; pulse; pupil. 2. Symbol for the element phosphorus. 3. Symbol for partial pressure, preferably italicized. 4. Probability. 5. A respirator designation, indicating that an airway protective mask is oil-proof.


page; probability (in statistics); pupil.


Symbol for the isotope of phosphorus with mass number 15; radioactive; atomic mass (weight) 15.


pulmonic second sound.


In chemistry, an abbreviation of para-.


after- or post-.


SEE: under gene.


1-phenyl-2-propanone, a chemical used in the synthesis of amphetamines.

P 0.1

The inspiratory mouth occlusion pressure measured 0.1 seconds after a breath initiates. Higher pressures are found in those mechanically ventilated patients who are more difficult to wean from ventilatory support. A more negative pressure implies a patient with an increased ventilatory demand (shortness of breath) and a less negative pressure means a patient is obtunded or has weak respiratory muscles.


physician assistant; posteroanterior; pulmonary artery.

P& A

percussion and auscultation.


1. Symbol for the element protactinium. 2. Abbreviation of pascal.


physician assistant.


(pon) [Hindi pān] The leaf of the betel tree (Piper betle). Chewing paan is common in the Indian subcontinent, Southeast Asia, and Indonesia. Betel leaf is a stimulant and is associated with the development of oral cancers.


The oxygen pressure gradient between the alveoli and the arterial blood.


(pab′yŭ-lŭm) [L. pabulum, food, nourishment] Food or nourishment; esp. in an absorbable solution.


premature atrial contraction.


(pās) Patient Advise and Consent Encounter.


(pās′māk″ĕr) 1. Anything that influences the rate and rhythm of occurrence of an activity or process. 2. In cardiology, a specialized cell or group of cells that automatically generates impulses that spread to other regions of the heart. The normal cardiac pacemaker is the sinoatrial node, a group of cells in the right atrium near the entrance of the superior vena cava. SYN: pacer. 3. A generally accepted shorthand term for an artificial cardiac pacemaker. SEE: artificial cardiac p.

artificial cardiac p. A device that can trigger mechanical ...

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