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(pū′pĭ-lĕr-ē) [L. pupilla, pupil] Pert. to the pupil.


(pū-pĭl-ŏm′ĕ-tĕr) [″ + Gr. metron, measure] A device for measuring the diameter of a pupil.


(pū-pĭl-lŏm′ĕ-trē) [″ + metron, measure] Measurement of the diameter of the pupil. In sleep medicine research, pupillary measurements are used to determine arousal versus drowsiness.


(pūr) Free from pollution; uncontaminated.


(pŭr-gā′shŭn) [L. purgatio] 1. Cleansing. 2. Evacuation of the bowels by the action of a purgative medicine. SYN: catharsis.


(pŭr′gă-tĭv) [L. purgativus] 1. Cleansing. 2. An agent that will stimulate the production of bowel movements. SEE: catharsis; cathartic.


(pŭrj) [L. purgare, to cleanse] 1. To evacuate the bowels by means of a cathartic. 2. A drug that causes evacuation of the bowels. 3. Removal of malignant or other pathologic cells from bone marrow.


(pŭr′jĭng) In eating disorders, the act of eliminating ingested calories, either by vomiting or by evacuation of the bowels. Purging behaviors may include misuse of emetics, diuretics, laxatives, or enemas.

purified protein derivative

ABBR: PPD. SEE: tuberculin.


(pū′rĭ-form) [L. pus, pus, + forma, shape] Resembling pus. SEE: puruloid.


(pū′rēn″) [L.purum, pure, + uricus, uric acid] The parent compound of nitrogenous bases, including adenine, guanine, xanthine, caffeine, and uric acid. Purines (chemical formula C5H4N4) are the end products of nucleoprotein digestion, and are catabolized to uric acid, which is excreted by the kidneys. Adenine and guanine are synthesized within cells for incorporation into DNA and RNA. SEE: aminopurine; oxypurine; methyl purine.

endogenous p. Purine originating from nucleoproteins within the tissues.

exogenous p. Purine present in, or derived from, foods. SEE: table.

purine base

Any of a group of chemical compounds that have a purine as their base. Such bases include xanthine, hypoxanthine, uric acid, and theobromine.


[L. puruis, clean, pure, unmixed] The state of being free of contamination.

Purkinje, Johannes E. von, Purkinĕ

(poor′kin-ye, -yā) Jan Evangelista Purkinje, Bohemian anatomist and physiologist, 1787–1869.

P. cell A large cerebellar cortex neuron with an ornate, antler-shaped dendritic arbor. Purkinje cells receive inputs (climbing fibers) from the inferior olive, and they send their axons (inhibitory) to the cerebellar and vestibular ...

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