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(bī-tem′pŏ-răl) [bi- + temporal] Pert. to both temples or temporal bones.

Bitot spots

(bē′tō) [Pierre A. Bitot, Fr. physician, 1822–1888] Triangular shiny gray spots on the conjunctiva seen in vitamin A deficiency.


(bĭt′ĕr) [AS. biter, strong] Having a caustic, sharp, or disagreeable taste. It is one of the five taste senses (bitter, salty, savory, sour, and sweet).

bitter melon

A bitter tropical Asian vegetable (Momordica charantia), having many local names, including balsam apple, balsam pear, bitter gourd, bitter squash, cerasee, karela, ku gua, and squirting cucumber. It is promoted in complementary and alternative medicine for its effects on diabetes mellitus, HIV infection, and obesity.

bitter orange

A citrus tree (Citrus aurantium) whose oils are used in some cultures as an oral remedy for gastrointestinal conditions such as constipation or nausea. Bitter orange is commonly used in dietary supplements as an aid to fat loss and as an appetite suppressant.

image Bitter orange can worsen cardiovascular disease and glaucoma.


(bī″yŭ-ret′, bī′yŭ-ret″) [bi- + urea] NH2CONHCONH2, a crystalline decomposition derivative of urea.

biuret reaction

(bī″yŭ-ret′, bī′yŭ-ret″) A method for detecting or measuring protein in body fluids, e.g., serum or saliva. The presence of biuret can be detected by the addition of sodium hydroxide and copper sulfate solutions to the sample. A rose to violet color indicates the presence of protein, and a pink and finally blue color indicates the presence of urea. SYN: biuret test.

biuret test

(bī″yŭ-ret′, bī′yŭ-ret″) Biuret reaction.


Biventricular assist device.


(bī-vā′lĕnt) [″ + valens, powerful] 1. In chemistry, having an valence of two. 2. In cytology, a structure consisting of two paired homologous chromosomes, each split into two sister chromatids during meiosis.


(bī-văr′ē-ĭt, āt″) [″ + ″] Pertaining to two variables.


(bĭks′ĕl) [Fr. b(eam) + (pi)xel] A beam element or ray in radiation oncology.

Bjerrum, Jannik Petersen

(byer′um) Danish ophthalmologist, 1851–1920.

B.'s screen Tangent screen.

B.'s scotoma A sickle- or comet-shaped blind spot usually found in the central zone of the visual field; seen in glaucoma.

Bjork-Shiley heart valve, Björk-Shiley heart valve

[Viking Olov Björk, Swedish heart surgeon, 1918–2009; Donald Pearce Shiley, U.S. engineer, 1920–2010] A synthetic artificial heart valve that is no ...

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