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Repetitive arranging, handling, or sorting of objects. It can occur in patients with Parkinson disease who are treated with dopaminergic drugs (such as levodopa), and in patients who abuse methamphetamines.


(pŭn′jĕn-sē) [L. pungens, prick] The quality of being sharp, strong, or bitter, as an odor or taste.


(pŭn′jĕnt) Acrid or sharp, as applied to an odor or taste.

Punnett square

[Reginald Crundall Punnett, Brit. geneticist, 1875–1967.] In genetics, a rectangular grid showing the gametes of each parent and all their possible offspring, thus indicating all-possible outcomes of a genetic cross.


(pū′pă, pū′pē″, pū′pī″) pl. pupae [L. pupa, girl, doll, puppet] The stage in complete metamorphosis of an insect during which a larva transforms into an imago (adult). The pupa does not feed during this stage and appears to be inactive; the internal activity is not visible. SEE: imago (3); larva (1).


(pū′pē″, pū′ pī″) Plural of pupa.


(pū′pĭl) [L. pupilla, little doll (the reflection in the pupil)] The contractile opening at the center of the iris of the eye. It is constricted when exposed to strong light and when the focus is on a near object; is dilated in the dark and when the focus is on a distant object. Average diameter is 4 to 5 mm. The pupils should be equal. SEE: pupilla; illus.




The upper image shows constriction; the lower, dilation.


 DIFFERENTIAL DIAGNOSIS: Constriction of the pupil occurs, for example, in bright light and after exposure to drugs such as morphine, pilocarpine, physostigmine, eserine, and other miotics.

 Dilation of the pupil is most often observed after treatment with mydriatic drugs (such as atropine, scopolamine, or homatropine), but may also be caused by paralysis of cranial nerve III, intracranial masses or trauma, sympathetic nervous system stimulation, and other pupillary stimuli.

Adie p. SEE: under Adie, William John.

Argyll Robertson p. SEE: Argyll Robertson pupil.

artificial p. A pupil made by iridectomy when the normal pupil is occluded.

bounding p. Rapid dilatation of a pupil, alternating with contraction.

Bumke p. Dilatation of the pupil owing to psychic stimulus.

cat’s-eye p. A pupil that is narrow and slitlike.

cornpicker’s p. Dilated pupils found in agricultural workers who are exposed to dust from jimsonweed. The dust contains stramonium, a mydriatic.

fixed p. A pupil that does not react ...

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