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Medical Dictionary


clitoridectomy (klit′o-ri-dek′to-me)
Removal of the clitoris. [clitoris + G. ektome, excision]

clitoriditis (klit′o-ri-di′tis)
Inflammation of the clitoris. SYN: clitoritis. [clitoris + G. -itis, inflammation]

clitoris, pl .clitorides (klit′o-ris, -tor′i-dez; kli′to-ris) [TA]
A cylindric, erectile body, rarely exceeding 2 cm in length, situated at the most anterior portion of the vulva and projecting between the branched limbs or laminae of the labia minora, which form its prepuce and frenulum. It consists of a glans, a corpus, and two crura, and is the homolog of the penis in the male, except that it is not perforated by the urethra and does not possess a corpus spongiosum. [G. kleitoris]

clitorism (klit′o-rizm)
Prolonged and usually painful erection of the clitoris; the analogue of priapism.

clitoritis (klit-o-ri′tis)
SYN: clitoriditis.

clitoromegaly (klit′or-o-meg′a-le)
An enlarged clitoris. [clitoris + G. megas, great]

clitoroplasty (klit′o-ro-plas′te)
Any plastic surgery procedure on the clitoris. [clitoris + G. plastos, formed]

clival (kli′val)
Pertaining to the clivus.

clivus, pl .clivi (kli′vus, -ve) [TA]
1. A downward sloping surface. 2. [TA] The sloping surface from the dorsum sellae to the foramen magnum composed of part of the body of the sphenoid and part of the basal part of the occipital bone. SYN: Blumenbach c.. [L. slope] Blumenbach c. SYN: c. (2) . c. ocularis the sloping walls of the fovea leading to the foveola.

cloaca (klo-a′ka)
1. In early embryos, the endodermally lined chamber into which the hindgut and allantois empty. 2. In birds and monotremes, the common chamber into which open the hindgut, bladder, and genital ducts. [L. sewer] ectodermal c. the proctodeum of the embryo. endodermal c. terminal portion of the hindgut internal to the cloacal membrane of the embryo. persistent c. a condition in which the urorectal fold has failed to divide the c. of the embryo into rectal and urogenital portions. SYN: sinus urogenitalis, urogenital sinus (2) .

cloacal (klo-a′kal)
Pertaining to the cloaca.

clobazam (klo-ba-zam)
A novel benzodiazepine psychotherapeutic agent in which the nitrogens in the heterocyclic ring are in the 1,5- rather than in the more usual 1,4- positions; an anxiolytic.

clobetasol propionate (klo-ba′ta-sol)
An anti-inflammatory corticosteroid usually used in topical preparations.

clocortolone (klo-kor′to-lon)
An anti-inflammatory corticosteroid usually used in topical preparations; available as the acetate and the pivalate.

clofazimine (klo-faz′i-men)
A tuberculostatic and leprostatic agent.

clofenamide (klo-fen′a-mid)
A diuretic. SYN: monochlorphenamide.

clofibrate (klo′fi-brat)
An antilipemic agent that reduces plasma levels of cholesterol, triglycerides, and uric acid; used in the treatment of hypercholesterolemia and atherosclerosis.

clogestone acetate (klo-jes′ton)
A progestational agent.

clomacran phosphate (klo′ma-kran)
A tranquilizer.

clomegestone acetate (klo-me-jes′ton)
A progestational drug.

clomiphene citrate (klo′mi-fen)
An analog of the nonsteroid estrogen, chlorotrianisene; a pituitary gonadotropin stimulant used therapeutically to induce ovulation; it competes with estrogen at the hypothalamic level, interrupting the negative feedback system and resulting in increased gonadotropin secretion; use often results in multiple births. SYN: chloramiphene.

clomipramine hydrochloride (klo-mip′ra-men)
An antidepressant.

clonal (klo′nal)
Pertaining to a clone.

clonazepam (klo-na′ze-pam)
An anticonvulsant drug in the benzodiazepine class.

clone (klon)
1. A colony or group of organisms (or an individual organism), or a colony of cells derived from a single organism or cell by asexual reproduction, all having identical genetic constitutions. 2. To produce such a colony or individual. 3. A short section of DNA that has been copied by means of gene cloning. See cloning. 4. A homogeneous population of DNA molecules. [G. klon, slip, cutting used for propagation] cDNA c. a duplex DNA, representing an mRNA, carried in a cloning vector. genomic c. a cell with a vector containing a fragment of DNA from a different organism.

clonic (klon′ik)
Relating to or characterized by clonus.

clonicity (klon-is′i-te)
The state of being clonic.

clonicotonic (klon′i-ko-ton′ik)
Both clonic and tonic; said of certain forms of muscular spasm.

clonidine hydrochloride (klo′ni-den)
An antihypertensive agent with central and peripheral actions; it stimulates adrenergic receptors in the brain leading to reduced sympathetic nervous system output; used as an adjunct to lessen drug withdrawal symptoms.

cloning (klon′ing)
1. Growing a colony of genetically identical cells or organisms in vitro. 2. Transplantation of a nucleus from a somatic cell to an ovum, which then develops into an embryo; many identical embryos can thus be generated by asexual reproduction. 3. With blastocysts, dividing a cluster of cells through microsurgery and transferring one-half of the cells to a zona pellucida that has been emptied of its contents. The resulting embryos, genetically identical, may be implanted in an animal for gestation. 4. A recombinant DNA technique used to produce millions of copies of a DNA fragment. The fragment is spliced into a c. vehicle ( i.e., plasmid, bacteriophage, or animal virus). The c. vehicle penetrates a bacterial cell or yeast (the host), which is then grown in vitro or in an animal host. In some cases, as in the production of genetically engineered drugs, the inserted DNA becomes activated and alters the chemical functioning of the host cell.The successful c. of an apparently normal and fertile sheep has shown the possibilities of the technique, but announcement of a proposal to clone a human being has generated controversy and threats of legal prohibition. Opponents of human c. object to the experimental creation of human embryos that would never have the opportunity for implantation and whose eventual destruction would be tantamount to abortion. Many bioethics authorities object even to implantation of an artificially created human embryo into a human uterus. Supporters of c. research fear that legal prohibition will impede needed investigations into human reproduction and infertility. In 1997 the National Bioethics Advisory Commission, after considering the scientific and ethical dimensions of c., recommended a 5-year ban on all human c. research. Nineteen European nations have signed an agreement prohibiting the artificial genetic replication of human beings. A/T c. c. of fragments where the only overhanging (or uncomplemented) ends are the A or T bases; occurs often in use of specific enzymes to cut or make DNA fragments. positional c. SYN: reverse genetics.

clonism (klon′izm)
A long continued state of clonic spasms.

clonogenic (klo-no-jen′ik)
Arising from or consisting of a clone.

clonograph (klon′o-graf)
An instrument for registering the movements in clonic spasm. [G. klonos, tumult, + grapho, to write]

clonorchiasis (klo-nor-ki′a-sis)
A disease caused by the fluke Clonorchis sinensis, affecting the distal bile ducts of humans and other fish-eating animals after ingestion of raw, smoked, or undercooked fish or raw crayfish; initial infection may be benign, but repeated or chronic infection induces an intense proliferative and granulomatous condition. SYN: clonorchiosis.

clonorchiosis (klo-nor-ke-o′sis)
SYN: clonorchiasis.

Clonorchis sinensis (klo-nor′kis si-nen′sis)
The Asiatic liver fluke, a species of trematodes (family Opisthorchiidae) that in the Far East infects the bile passages of humans and other fish-eating animals; cyprinoid fish serve as chief second intermediate hosts, and various operculate snails serve as the first intermediate hosts. SYN: Opisthorchis sinensis.

clonus (klo′nus)
A form of movement marked by contractions and relaxations of a muscle, occurring in rapid succession seen with, among other conditions, spasticity and some seizure disorders. SEE ALSO: contraction. [G. klonos, a tumult] ankle c. a rhythmic contraction of the calf muscles following a sudden passive dorsiflexion of the foot, the leg being semiflexed. toe c. alternating movements of flexion and extension of the great toe following forcible extension at the metatarsophalangeal joint. wrist c. rhythmical contractions and relaxations of the muscles of the forearm excited by a forcible passive extension of the hand.

clopamide (klo-pam′id)
A diuretic and antihypertensive agent.

Hippolyte, French anatomist, 1787–1840. See C. space.

Jules G., French anatomist, 1790–1883. See C. canal, C. hernia, C. septum, proximal deep inguinal lymph node.

clorazepate (klor-az′e-pat)
The mono- or dipotassium salt is used as an anti-anxiety agent; a benzodiazepine prodrug for nordiazepam.

clorprenaline hydrochloride (klor-pren′a-len)
A bronchodilator. SYN: isoprophenamine hydrochloride.

clostridia (klos-trid′e-a)
Plural of clostridium.

clostridial (klos-trid′e-al)
Relating to any bacterium of the genus Clostridium.

clostridiopeptidase A (klos-trid′e-o-pep′ti-das)
SYN: Clostridium histolyticum collagenase.

clostridiopeptidase B
SYN: clostripain.

Clostridium (klos-trid′e-um)
A genus of anaerobic (or anaerobic, aerotolerant), spore-forming, motile (occasionally nonmotile) bacteria (family Bacillaceae) containing Gram-positive rods; motile cells are peritrichous. Many of the species are saccharolytic and fermentative, producing various acids and gases and variable amounts of neutral products; other species are proteolytic, some attacking proteins with putrefaction or more complete proteolysis. Some species fix free nitrogen. These organisms sometimes produce exotoxins; they are generally found in soil and in the mammalian intestinal tract, where they may cause disease. The type species is C. butyricum. [G. kloster, a spindle] C. bifermentans a bacterial species found in putrid meat and gaseous gangrene; also commonly found in soil, feces, and sewage. Its pathogenicity (largely due to an edema-producing toxin) varies from strain to strain. C. botulinum a bacterial species that occurs widely in nature and is a frequent cause of food poisoning (botulism) from preserved meats, fruits, or vegetables that have not been properly sterilized before canning. The main types, A to F, are characterized by antigenically distinct, but pharmacologically similar, very potent neurotoxins, each of which can be neutralized only by the specific antitoxin; group C toxin contains at least two components; the recorded cases of human botulism have been due mainly to types A, B, E, and F; infant botulism occurs when colonization of the gastrointestinal tract with C. botulinum results in absorption of the toxin through the gastrointestinal wall; type Cα causes botulism in domestic and wild water fowl; Cβ and D are associated with intoxications in cattle. Type E is usually associated with improperly processed fish products. C. butyricum a bacterial species that occurs in naturally soured milk, in naturally fermented starchy plant substances, and in soil; formerly considered nonpathogenic, it is now known to include neurotoxin-producing strains; the type species of the genus C.. C. cadaveris a bacterial species found in a human feces and in the pleural fluid of a sheep; it is not pathogenic for guinea pigs or rabbits, but has been a rare cause of gas gangrene in humans. C. carnis a bacterial species found in a rabbit inoculated with soil; it is pathogenic for laboratory animals, in which an exotoxin produces edema, necrosis, and death. C. chauvoei a bacterial species that causes blackleg, black quarter, or symptomatic anthrax in cattle and other animals and that produces an exotoxin. C. cochlearium a bacterial species found in human war wounds and septic infections; it is not pathogenic for guinea pigs. C. difficile (di-fi′-sel) a bacterial species found in feces of humans and animals. It colonizes newborn infants, who are spared from toxin induced diarrheal disease. Pathogenic for human beings, guinea pigs, and rabbits; frequent cause of colitis and diarrhea following antibiotic use. Found to be a cause of pseudomembranous colitis and associated with a number of intestinal diseases that are linked to antibiotic therapy; also the chief cause of nosocomial diarrhea. [L. difficult] C. fallax a bacterial species found in war wounds, appendicitis, and black leg of sheep; it produces a weak exotoxin. C. haemolyticum a bacterial species found in cattle dying of icterohemoglobinuria; it is pathogenic and toxic for guinea pigs and rabbits and produces an unstable, hemolytic toxin. C. histolyticum a bacterial species found in war wounds, where it induces necrosis of tissue; it produces cytolytic exotoxins that cause local necrosis and sloughing on injection; it is not toxic on feeding; it is pathogenic for small laboratory animals. C. innominatum a bacterial species found in septic and gangrenous war wounds. C. nigrificans former name for Desulfotomaculum nigrificans. C. novyi a bacterial species consisting of three types, A, B, and C; type A, from a case of gaseous gangrene and from human necrotic hepatitis, produces γ-toxin (a hemolytic lecithinase); B, from black disease (infectious necrotic hepatitis) of sheep, produces β-toxin (a hemolytic lecithinase); and C, found in bacillary osteomyelitis of water buffaloes, does not produce toxin. SYN: C. oedematiens. C. oedematiens SYN: C. novyi. C. parabotulinum a bacterial species containing formerly referred to as C. botulinum types A and B; the types are identified by protection tests with known type antitoxin; it produces a powerful exotoxin and is pathogenic for humans and other animals. C. paraputrificum a bacterial species found in feces (especially of infants), gaseous gangrene, and postmortem fluid and tissue cultures; it is not pathogenic for rabbits or guinea pigs. C. perfringens a bacterial species that is the chief causative agent of gas gangrene in humans and a cause of gas gangrene in other animals, especially sheep; it may also be involved in causing enteritis, appendicitis, and puerperal fever; it is one of the most common causes of food poisoning in the U. S. This organism is found in soil, water, milk, dust, sewage, and the intestinal tract of humans and other animals. SYN: C. welchii, gas bacillus, Welch bacillus. C. ramosum a bacterial species found in the natural cavities of humans and other animals as well as in seawater and in feces; it is also found in association with mastoiditis, otitis, pulmonary gangrene, putrid pleurisy, appendicitis, intestinal infections, balanitis, liver abscess, osteomyelitis, septicemia, and urinary infections. It was formerly the type species of the obsolete genus Ramibacterium. C. septicum a bacterial species found in malignant edema of animals, in human war wounds, and in cases of appendicitis; it is pathogenic for guinea pigs, rabbits, mice, and pigeons and produces an exotoxin that is lethal and hemolytic. SYN: Vibrion septique. C. sordellii a bacterial strain that produces multiple toxins including a lecithinase, hemolysin, and a fibrinolysin, which result in edema and potentially fatal hypotension, and necrotic infections in humans. It is especially associated with abdominal and gynecologic posttraumatic and postoperative wound infection; also causes big head in rams. C. sphenoides a bacterial species found in gangrenous war wounds; it is not pathogenic for guinea pigs or rabbits. C. sporogenes a bacterial species found in intestinal contents, gaseous gangrene, and soil; it is not pathogenic for guinea pigs or rabbits, but does produce a slight, temporary, local tumefaction. C. tertium a bacterial species found in wounds, but that is nonpathogenic for laboratory animals. C. tetani the bacterial species that causes tetanus; it produces a potent exotoxin (neurotoxin) that is intensely toxic for humans and other animals when formed in tissues or injected, but not when ingested. C. thermosaccharolyticum a bacterial species of thermophilic bacteria found in “hard swell” of canned goods; it is not pathogenic to laboratory animals. C. welchii SYN: C. perfringens.

clostridium, pl .clostridia (klos-trid′e-um, -a)
A vernacular term used to refer to any member of the genus C..

Clostridium histolyticum collagenase
An enzyme that catalyzes the hydrolysis of collagen, preferentially at peptide bonds on the amino side of a glycylprolyl sequence. SYN: clostridiopeptidase A, collagenase A, collagenase I, microbial collagenase.

Clostridium histolyticum proteinase B
SYN: clostripain.

clostripain (klos′tri-pan)
A cysteine proteinase cleaving preferentially at the carboxyl side of arginyl and lysyl residues. It also has an esterase activity. SYN: clostridiopeptidase B, Clostridium histolyticum proteinase B.

closure (klo′zhur)
1. The completion of a reflex pathway. 2. The place of coupling between stimuli in the establishment of conditioned learning. 3. To achieve or experience a sense of completion in a mental task. flask c. in dentistry, the procedure of bringing the two halves or parts of a flask together; trial flask closures are preliminary closures made to eliminate excess denture-base material and to ensure that the mold is completely filled; the final flask c. is the last c. of a flask before curing, following trial packing of the mold with denture-base material. velopharyngeal c. the apposition of the velum (soft palate) and the upper pharyngeal walls as in deglutition and in some speech sounds.

closylate (klo′si-lat)
USAN-approved contraction for p-chlorobenzenesulfonate.

clot (klot)
1. To coagulate, said especially of blood. 2. A soft, nonrigid, insoluble mass formed when a liquid ( e.g., blood or lymph) gels. [O.E. klott, lump] agonal c. intravascular thrombosis ascribed to the process of dying. antemortem c. a blood c., found at autopsy, formed in any of the heart cavities or the great vessels before death. blood c. the coagulated phase of blood; the soft, coherent, jelly-like red mass resulting from the conversion of fibrinogen to fibrin, thereby entrapping the red blood cells (and other formed elements) within the coagulated plasma. chicken fat c. c. formed in vitro or postmortem from leukocytes and plasma of sedimented blood. currant jelly c. a jellylike mass of red blood cells and fibrin formed by the in vitro or postmortem clotting of whole or sedimented blood. laminated c. a c. formed in a succession of layers such as occurs in the natural course of an aneurysm. passive c. a c. formed in an aneurysmal sac consequent to the cessation or slowing of circulation through the aneurysm. postmortem c. a c. formed in the heart or great vessels after death.

clotrimazole (klo-trim′a-zol)
An antifungal agent used topically to treat a variety of fungal and yeast infections.

clottage (klot′ij)
Obsolete term for blocking of any canal or duct by a blood clot.

Arthur M., U.S. zoologist and pathologist, *1901. See C. melanoma.

clove oil (klov)
SYN: oil of clove.

cloxacillin sodium (klok-sa-sil′in)
A penicillinase-resistant penicillin.

clozapine (klo′za-pen)
A sedative and antipsychotic tricyclic dibenzodiazepine regarded as atypical because of low central antidopaminergic activity.

Abbreviation for cognitive laterality quotient.

clubbing (klub′ing)
A condition affecting the fingers and toes in which proliferation of distal soft tissues, especially the nail beds, results in thickening and widening of the extremities of the digits; the nails are abnormally curved nail beds excessively compressible, and skin over them red and shiny. See Hippocratic nails, under nail. hereditary c. [MIM*119900] simple hereditary c. of the digits without associated pulmonary or other progressive disease, often more severe in males; most common in black patients; autosomal dominant inheritance. SYN: acropachy.

clubfoot (klub′fut)
SYN: talipes equinovarus.

clubhand (klub′hand)
Congenital or acquired angulation deformity of the hand associated with partial or complete absence of radius or ulna; usually with intrinsic deformities in the hand in congenital variants. radial c. c. with angular deviation toward radial side of limb associated with partial or complete absence of the radius. ulnar c. c. with angular deviation toward ulnar side of limb associated with partial or complete absence of the ulna.


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