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Medical Dictionary - Dictionary of Medicine and Human Biology

Medical Dictionary


caruncle (kar′ung-kl) [TA]
A small, fleshy protuberance, or any structure suggesting such a shape. SYN: caruncula (1) [TA] . lacrimal c. [TA] a small reddish body at the medial angle of the eye, containing modified sebaceous and sweat glands. SYN: caruncula lacrimalis [TA] . Morgagni c. SYN: middle lobe of prostate. Santorini major c. SYN: major duodenal papilla. Santorini minor c. SYN: minor duodenal papilla. urethral c. a small, fleshy, sometimes painful protrusion of the mucous membrane at the meatus of the female urethra; it may be telangiectatic, papillomatous, or composed of granulation tissue.

caruncula, pl .carunculae (ka-rung′ku-la, -le) [TA]
1. [TA] SYN: caruncle. 2. In ungulates, one of about 200 specific disklike areas of the uterine endometrium that, in conjunction with the fetal cotyledon, forms a placentome of the placenta; as a site of fetal-maternal contact, the c. remains constant in position but enlarges greatly during pregnancy. [L. a small fleshy mass, fr. caro, flesh] hymenal c. [TA] one of the numerous tabs or projections surrounding the orifice of the vagina. SYN: c. hymenalis [TA] , c. myrtiformis. c. hymenalis, pl .carunculae hymenales [TA] SYN: hymenal c.. c. lacrimalis [TA] SYN: lacrimal caruncle. c. myrtiformis, pl .carunculae myrtiformes SYN: hymenal c.. c. salivaris SYN: sublingual c.. sublingual c. [TA] a papilla on each side of the frenulum of the tongue marking the opening of the submandibular duct. SYN: c. sublingualis [TA] , c. salivaris. c. sublingualis [TA] SYN: sublingual c..

Karl G., German anatomist and zoologist, 1789–1869. See C. circle, C. curve.

carvacrol (kar′va-krol)
An isomer of thymol that occurs in several volatile oils (marjoram, origanum, savory, and thyme), with properties and activity that closely resemble those of thymol; has antiseptic properties, but is used chiefly as a perfume.

See Rivero-C..

carvedilol (kar′ve-dil-ol)
An agent used as an antihypertensive and antianginal, and in congestive heart failure.

carver (kar′ver)
A dental hand instrument, available in a wide variety of end shapes, used for forming and contouring wax, filling materials, etc.

Nucleus. See karyo-. [G. karyon, nut, kernel]

caryophyllus, caryophyllum (kar′e-o-fi′lus, -um)
Clove. [G. karyophyllon, clove tree, fr. karyon, nut, + phyllon, leaf]

caryotheca (kar′e-o-the′ka)
SYN: nuclear envelope. [caryo- + G. theke, sheath, box]

Gasper, Spanish physician, 1691–1759. See C. necklace.

casamino acids (kas′a-me′no)
Trivial term for the mixture of amino acids derived by hydrolysis of casein; used in bacterial and similar growth media.

cascade (kas-kad′)
1. A series of sequential interactions, as of a physiological process, which once initiated continues to the final one; each interaction is activated by the preceding one, sometimes with cumulative effect. 2. To spill over, especially rapidly. [Fr., fr. It. cascare, to fall]

cascara (kas-kar′a)
SYN: c. sagrada. c. amara the dried bark of a species of Picramnia (family Simarubaceae); used as a bitter tonic. SYN: Honduras bark. c. sagrada the dried bark of Rhamnus purshiana (family Rhamnaceae); used as a laxative. SYN: c..

case (kas)
1. An instance of disease with its attendant circumstances. Cf.:patient. 2. A box or container. [L. casus, an occurrence] borderline c. a patient, whose clinical findings are suggestive, but not fully convincing, of a specific diagnosis. index c. SYN: proband. trial c. in refraction, a box containing lenses for testing.

caseation (ka-se-a′shun)
A form of coagulation necrosis in which the necrotic tissue resembles cheese and contains a mixture of protein and fat that is absorbed very slowly; occurs particularly in tuberculosis. SEE ALSO: caseous necrosis. SYN: tyrosis (2) . [L. caseus, cheese]

casein (ca′se-in, ka′sen)
The principal protein of cow's milk and the chief constituent of cheese. It is insoluble in water, soluble in dilute alkaline and salt solutions, forms a hard insoluble plastic with formaldehyde, and is used as a constituent of some glues; various components are designated α-, β-, and κ-caseins. β-C. is converted to γ-c. by milk proteases. There are several isoforms of α-c.. κ-C. is not precipitated by calcium ions. c. iodine, iodinated c. a compound of c. with iodine formed by incubating the protein with the element, which becomes attached to tyrosine groups in the protein. SYN: caseo-iodine. plant c. SYN: avenin.

caseinate (ka′se-in-at)
A salt of casein.

caseinogen (ka-se-in′o-jen)
“Soluble” or κ-casein which, when acted upon by rennin, is converted into paracasein.

caseo-iodine (ka′se-o-i′o-din)
SYN: casein iodine.

caseose (ka′se-os)
Nondescript term for product resulting from the hydrolysis or digestion of casein.

caseous (ka′se-us)
Pertaining to or manifesting the gross and microscopic features of tissue affected by caseation.

Tommaro, Italian physician, 1880–1933. See C. antigen, C. intradermal test, C. skin test.

cassava starch (ka-sah′vah)
SYN: tapioca.

William E., U.S. laryngologist, 1858–1916. See C. position.

Casser, Casserio
Giulio, Italian anatomist, 1556–1616. See C. fontanelle, C. perforated muscle.

casserian (ka-se′re-an)
Relating to or described by Casser.

cassette (ka-set′)
1. A plate, film, or tape holder for use in photography or radiography. A radiographic c. contains two intensifying screens and a sheet of x-ray film. 2. A perforated holder in which tissue blocks are placed for paraffin embedding. [Fr., dim. of casse, box] susceptibility c. a common sequence of amino acids in residues 70–74 in the HLA-DRB1 chains, found in alleles associated with rheumatoid arthritis. It is one of two variations: glutamine[Q]-lysine[K]-arginine[R]-alanine[A]-alanine[A] or QRRAA. These susceptibility cassettes are found in many different DRB1 alleles. The alpha and beta chains that form these antigen-presenting molecules have a configuration not unlike a trough or rain gutter; antigens are bound by sequences of amino acids in a pocket along the bottom and sides of the trough or cavity, and this complex forms a heterotrimer with the T-cell receptor on CD4+ cells. SYN: rheumatoid pocket, shared epitope.

cassia bark (kash′ya)
SYN: cinnamon.

cassia fistula
The dried ripe fruit of C., used as a laxative. SYN: purging cassia.

cassia oil
SYN: cinnamon oil.

cast (kast)
1. An object formed by the solidification of a liquid poured into a mold. 2. Rigid encasement of a part, as with plaster, plastic, or fiberglass, for purposes of immobilization. 3. An elongated or cylindrical mold formed in a tubular structure ( e.g., renal tubule, bronchiole) that may be observed in histologic sections or in material such as urine or sputum; results from inspissation of fluid material secreted or excreted in the tubular structures. 4. Restraint of a large animal, usually a horse, with ropes and harnesses in a recumbent position. 5. In dentistry, a positive reproduction of the form of the tissues of the upper or lower jaw, which is made by the solidification of plaster, metal, etc., poured into an impression, and over which denture bases or other dental restorations may be fabricated. [M.E. kasten, fr. O.Norse kasta] bacterial c. a c. in the urine composed of bacteria. blood c. a c. usually formed in renal tubules, but may occur in bronchioles; consists of inspissated material that includes various elements of blood ( i.e., erythrocytes, leukocytes, fibrin, and so on), resulting from bleeding into the glomerulus or tubule, or into the alveolus or bronchiole. coma c. a renal c. of strongly refracting granules said to be indicative of imminent coma in diabetes. SYN: Külz cylinder. decidual c. a mold of the interior of the uterus formed of the exfoliated mucous membrane in cases of extrauterine gestation. dental c. a positive likeness of a part or parts of the oral cavity. diagnostic c. a positive replica of the form of the teeth and tissues made from an impression. epithelial c. a c. that contains epithelial cells and their remnants; occurs most frequently in renal tubules and urine as a marker for renal tubular necrosis. false c. an elongated, ribbonlike mucous thread with poorly defined edges and pointed or split ends, often confused with a true urinary c.. SYN: cylindroid, mucous c., pseudocast, spurious c.. fatty c. a renal or urinary c. consisting largely of fat globules; those containing doubly refractile bodies (composed of cholesterol) are found in the nephrotic syndrome. fibrinous c. a yellow c. that somewhat resembles a waxy c.; more likely to occur in the urine of certain patients with acute nephritis. granular c. a relatively dark, dense urinary c. of coarsely or finely particulate cellular debris and other proteinaceous material, frequently seen in chronic renal disease but also in the recovery phase of acute renal failure. SEE ALSO: waxy c.. hair c. a c. composed of parakeratotic scales attached to scalp hair but freely movable up and down the hair shaft; found in scaling dermatitis of the scalp, including dandruff, psoriasis, and seborrheic dermatitis. SYN: pseudonit. halo c. a c. applied to the shoulders in which metal bars are set that extend over the head to a halo, from which traction may be applied to the head by means of tongs or a halter. hyaline c. a relatively transparent renal c. seen in the urine and composed of proteinaceous material derived from disintegration of cells; seen in patients with renal disease or transiently with exercise, fever, congestive heart failure, and diuretic therapy. investment c. SYN: refractory c.. master c. a replica of the prepared tooth surfaces, residual ridge areas, and/or other parts of the dental arch as reproduced from an impression. mucous c. SYN: false c.. red blood cell c. a urinary c. composed of a matrix containing red cells in various stages of degeneration and visibility, characteristic of glomerular disease or renal parenchymal bleeding. SYN: red cell c.. red cell c. SYN: red blood cell c.. refractory c. a c. made of material that will withstand the high temperatures of metal casting or soldering without disintegrating. SYN: investment c.. renal c. any type of c. formed in a renal tubule, and found in the urine consisting of various materials, e.g., albumin, cells, blood. SYN: tube c.. spica c. a c. of layers overlapping in a V pattern, covering two body parts greatly different in size, as the hip and waist, thumb and wrist, etc. spurious c. SYN: false c.. tube c. SYN: renal c.. urinary casts casts discharged in the urine. waxy c. a form of urinary c. consisting of homogeneous proteinaceous material that has a high refractive index, in contrast to the low refractive index of hyaline casts; waxy casts probably represent an advanced stage of the disintegrative process that results in coarsely and finely granular casts, and are usually indicative of advanced renal disease. white blood cell c. a urinary c. composed of polymorphonuclear leukocytes, characteristic of tubulointerstitial disease, especially pyelonephritis. white cell c. a c. in the urine composed of white blood cells.

cast brace (kast bras)
A specially designed plaster or plastic cast incorporating hinges and other brace components; used in the treatment of fractures to provide immobilization and to promote early activity and early joint motion.

Sir Aldo, Italian physician, 1877–1971. See C. bronchitis, C. paint.

casting (kas′ting)
1. A metallic object formed in a mold. 2. The act of forming a c. in a mold. centrifugal c. c. molten metal into a mold by spinning the metal from a crucible at the end of a revolving arm. ceramo-metal c. a c. made of alloys containing or excluding precious metals, to which dental porcelain can be fused. gold c. a c. made of gold, usually formed to represent and replace lost tooth structure. vacuum c. the c. of a metal in the presence of a vacuum.

William B., U.S. physician, 1897–1991. See C. intrinsic factor.

Benjamin, U.S. pathologist, 1906–1982. See C. disease.

castor bean (kas′ter ben)
SYN: Ricinus.

castor oil
A fixed oil expressed from the seeds of Ricinus communis (family Euphorbiaceae); a purgative. aromatic c. contains cinnamon oil 3, clove oil 1, vanillin 1, saccharin 0.5, alcohol 30, in c. to make 1000; a cathartic.

castrate (kas′trat)
To remove the testicles or the ovaries. [L. castro, pp. -atus, to deprive of generative power (male or female)]

castration (kas-tra′shun)
1. Removal of the testicles or ovaries. 2. See c. complex, castrate. functional c. gonadal atrophy produced by prolonged treatment with sex hormones.

casualty (kazh′oo-al-te)
An injury, or the victim of an accident.

Abbreviation for chloramphenicol acetyl transferase; obsolete abbreviation for computerized axial tomography (CT).

Down; opposite of ana-. SEE ALSO: kata-. Cf.:de-. [G. kata, down]

catabasial (kat-a-ba′se-al)
Denoting a skull in which the basion is lower than the opisthion. [cata- + Mod. L. basion]

catabiotic (kat′a-bi-ot′ik)
Used up in the carrying on of the vital processes other than growth, or in the performance of function, referring to the energy derived from food. [cata- + G. biotikos, relating to life]

catabolic (kat-a-bol′ik)
Relating to or promoting catabolism.

catabolism (ka-tab′o-lizm)
1. The breaking down in the body of complex chemical compounds into simpler ones ( e.g., glycogen to CO2 and H2O), often accompanied by the liberation of energy. 2. The sum of all degradative processes. SYN: dissimilation (2) . Cf.:anabolism, metabolism. [G. katabole, a casting down]

catabolite (ka-tab′o-lit)
Any product of catabolism.

catachronobiology (kat′a-kron′o-bi-ol′o-je)
The study of the deleterious effects of time on a living system. [cata- + G. chronos, time, + biology]

catacrotic (kat-a-krot′ik)
Denoting a pulse tracing in which the downstroke is interrupted by one or more upward waves.

catacrotism (ka-tak′ro-tizm)
A condition of the pulse in which there are one or more secondary expansions of the artery following the main beat, producing secondary upward waves on the downstroke of the pulse tracing. [cata- + G. krotos, beat]

catadicrotic (kat′a-di-krot′ik)
Denoting a pulse tracing in which there are two minor elevations interrupting the downstroke.

catadicrotism (kat-a-di′kro-tizm)
A condition of the pulse marked by two minor expansions of the artery following the main beat, producing two secondary upward waves on the downstroke of the pulse tracing. [cata + G. di-, two, + krotos, beat]

catadidymus (kat-a-did′i-mus)
SYN: duplicitas anterior. [cata- + G. didymus, twin]

catadioptric (kat-a-di-op′trik)
Employing both reflecting and refractive optical systems.

catadromous (kat-a-dro′mus)
Migrating from fresh water to the ocean to spawn. SEE ALSO: anadromous.

catagen (kat′a-jen)
A regressing phase of the hair growth cycle during which cell proliferation ceases, the hair follicle shortens, and an anchored club hair is produced.

catagenesis (kat-a-jen′e-sis)
SYN: involution. [cata- + G. genesis, origin]

catalase (kat′a-las)
A hemoprotein catalyzing the decomposition of hydrogen peroxide to water and oxygen (2H2O2 → O2 + 2H2O); a deficiency of c. is associated with acatalasemia.

catalepsy (kat′a-lep-se)
A condition characterized by waxy rigidity of the limbs, which may be placed in various positions that are maintained for a time, lack of response to stimuli, mutism and inactivity; occurs with some psychoses, especially catatonic schizophrenia. [G. katalepsis, a seizing, c., fr. kata, down, + lepsis, a seizure]

cataleptic (kat-a-lep′tik)
Relating to, or suffering from, catalepsy.

cataleptoid (kat-a-lep′toyd)
Simulating or resembling catalepsy.

catalysis (ka-tal′i-sis)
The effect that a catalyst exerts upon a chemical reaction. [G. katalysis, dissolution] contact c. a process wherein the catalyst is a solid and the catalyzed reaction is produced after the reactants (usually gases) have made contact with the solid. surface c. c. at the surface of a solid particle or interface, or of a macromolecule.


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