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partial thromboplastin time.


(tī′ă-lĭn) [Gr. ptyallon, saliva + -in] A salivary enzyme that hydrolyzes starch and glycogen to maltose and a small amount of glucose. The optimum pH for ptyalin activity is 6.9. SYN: amylase, salivary. SEE: enzyme; ptyalism; saliva.


(tī′ă-lĭzm) [″ + -ismos, condition] Excessive secretion of saliva. This may be due to pregnancy, stomatitis, rabies, exophthalmic goiter, menstruation, epilepsy, hysteria, nervous conditions, and gastrointestinal disorders and may be induced by mercury, iodides, pilocarpine, and other drugs. SYN: hyperptyalism; hypersalivation; salivation. SEE: xerostomia.


Symbol for the element plutonium.


(pū′bar″kē) [puber + Gr. archē, beginning] 1. The beginning of puberty. 2. Beginning development of pubic hair. SEE: semenarche; thelarche.

premature p. The development of pubic hair on a female child before 8 years of age, or on a male before the age of 9.


(pū′bĕr) [L., grown up] One at the onset of puberty.


(pū′bĕr-ăl) [L. pubertas, puberty] Pubertal.


(pu″bĕr-fō′nē-ă) [puber + phono- + -ia] Persistence of a highpitched, childlike voice in adolescents or young adults who have already achieved puberty.


(pū′bĕr-tăl) Pert. to puberty.


(pu′bĕrt-ē) [Fr. puberté fr. L. pubertas, (age of) manhood, adult] The stage in life during which individuals become capable of reproduction. In human beings puberty typically develops in boys between the ages of 12 and 15, and in girls, between 9 and 16. SEE: onset of puberty.

delayed p. In the U.S., puberty that has not begun by the age of 12 in girls or 14 in boys, i.e., 2 or more standard deviations from the mean age at which puberty is noted in others.

precocious p. The appearance of secondary sex characteristics in girls under 8 and in boys under 9. The pituitary and hypothalamus glands may be involved, or the condition may result from premature secretion of sex hormones not caused by pituitary or hypothalamic action. Gonadotropin-releasing hormone (GnRH) has been used to treat this condition. SYN: isosexual precocity; pubertas praecox; sexual precocity.


(pu′bēz) pl. pubes [L. pubes, of ripe age, grown up, adult] 1. The region just above the genitalia in which pubic hair grows. 2. Pubic hair.


(pū-bĕs′ĕns) [L. pubescens, becoming hairy] 1. Puberty or the approach of puberty. ...

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