English dictionary of medical terms (68)

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[Multilingual]No:1340 - photosensitivity
(photo- + sensitivity) an abnormal cutaneous response involving the interaction between photosensitizing substances and sunlight or filtered or artificial light at wavelengths of 280-400 mm. There are two main types : photoallergy and photoxicity.
[Multilingual]No:1341 - photosensitization
the development of abnormally heightened reactivity of the skin to sunlight.
[Multilingual]No:1342 - physical
pertaining to the body, to material things, or to physics.
[Multilingual]No:1343 - physicochemical
pertaining to physics and chemistry.
[Multilingual]No:1344 - physiologic
normal; not pathologic; characteristic of or conforming to the normal functioning or state of the body or a tissue or organ; physiological.
[Multilingual]No:1345 - pigmentation
1. the deposition of colouring matter; the coloration or discoloration of a part by pigment. 2. coloration, especially abnormally increased coloration, by melanin.
[Multilingual]No:1346 - piloerection
(pilo- + erection) erection of the hair.
[Multilingual]No:1347 - pityriasis
(Gr. pityron bran + -iasis) a name originally applied to a group of skin diseases characterized by the formation of fine, branny scales, but now used only with a modifier.
[Multilingual]No:1348 - placebo
(L. 'I will please') any dummy medical treatment; originally, a medicinal preparation having no specific pharmacological activity against the patient's illness or complaint given solely for the psychophysiological effects of the treatment; more recently, a dummy treatment administered to the control group in a controlled clinical trial in order that the specific and nonspecific effects of the experimental treatment can be distinguished - i.e., the experimental treatment must produce better results than the placebo in order to be considered effective.
[Multilingual]No:1349 - placenta
(L. 'a flat cake') an organ characteristic of true mammals during pregnancy, joining mother and offspring, providing endocrine secretion and selective exchange of soluble, but not particulate, blood-borne substances through an apposition of uterine and trophoblastic vascularized parts. According to species, the area of vascular apposition may be diffuse, cotyledonary, zonary or discoid; the nature of apposition may be labyrinthine or villous; the intimacy of apposition may vary according to what layers are lost of those originally interposed between maternal and fetal blood (maternal endothelium, uterine connective tissue, uterine epithelium, chorion, extraembryonic mesoderm, and endothelium of villous capillary). The chorion may be joined by and receive blood vessels from either the yolk sac or the allantois, and the uterine lining may be largely shed with the chorion at birth (deciduate) or may separate from the chorion and remain (nondeciduate). The human placenta is discoid, villous, haemochorial, chorioallantoic, and deciduate. After birth, it weighs about 600 gm. and is about 16 cm. in diameter and 2 cm. thick, discounting a principal functional part, the maternal blood in the intervillous space (which leaks out at birth) into which the chorionic villi dip. The villi are grouped into adjoining cotyledons making about 20 velvety bumps on the side of the placenta facing outward to the uterus; the inner side of the placenta facing the fetus is smooth, being covered with amnion, a thin avascular layer that continues past the edges of the placenta to line the entire hollow sphere of chorion except where it is reflected to cover the umbilical cord, which joins fetus and placenta. The cord usually joins the placenta near the centre but may insert at the edge, on the nonplacental chorion, or on an accessory placenta.
[Multilingual]No:1350 - plasma expander
artificial plasma extender.
[Multilingual]No:1351 - plasma protein
one of the hundreds of different proteins present in blood plasma, including carrier proteins ( such albumin, transferrin, and haptoglobin), fibrinogen and other coagulation factors, complement components, immunoglobulins, enzyme inhibitors, precursors of substances such as angiotension and bradykinin, and many other types of proteins.
[Multilingual]No:1352 - plasminogen
the inactive precursor of plasmin (=enzyme that catalyses the hydrolysis of peptide bonds at the carbonyl end of lysine or arginine residues).
[Multilingual]No:1353 - pleurisy
(Gr. pleuritis) inflammation of the pleura, with exudation into its cavity and upon its surface. It may occur as either an acute or a chronic process. In acute pleurisy the pleura becomes reddened, then covered with an exudate of lymph, fibrin, and cellular elements (the dry stage); the disease may progress to the second stage, in which a copious exudation of serum occurs (stage of liquid effusion). The inflamed surfaces of the pleura tend to become united by adhesions, which are usually permanent. The symptoms are a stitch in the side, a chill, followed by fever and a dry cough. As effusion occurs there is an onset of dyspnea and a diminution of pain. The patient lies on the affected side.
[Multilingual]No:1354 - plexus
(L. 'braid) a network or tangle; (NA) a general term for a network of lymphatic vessels, nerves, or veins.
[Multilingual]No:1355 - pneumonia
(Gr. pneumonia) inflammation of the lungs with consolidation.
[Multilingual]No:1356 - pneumonopath
(pneumono- + Gr. pathos disease) any disease of the lung.
[Multilingual]No:1357 - poliomyelitis
(polio- + Gr. myelos marrow + -itis) an acute viral disease, occurring sporadically and in epidemics, and characterized clinically by fever, sore throat, headache, and vomiting, often with stiffness of the neck and back. In the minor illness these may be the only symptoms. The major illness, which may or may not be preceded by the minor illness, is characterized by involvement of the central nervous system, stiff neck, pleocytosis in the spinal fluid, and perhaps paralysis. There may be subsequent atrophy of groups of muscles, ending in contraction and permanent deformity. The major illness is called acute anterior p., infantile paralysis and Heine-Medin disease. The disease is now largely controlled by vaccines.
[Multilingual]No:1358 - polyarthritis
(poly- + Gr. arthron joint + -itis) an inflammation of several joints together.
[Multilingual]No:1359 - polydipsia
(poly- + Gr. dipsa thirst + -ia) chronic excessive thirst, as in diabetes mellitus or diabetes insipidus.
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