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Medical Dictionary


duction (duk′shun)
1. The act of leading, bringing, conducting. 2. In ophthalmology, ocular rotations with reference to one eye; usually additionally designating direction of movement of the eye; e.g., rotation toward the nose, adduction; toward the temple, abduction; upward, supra- or sursumduction; downward, deorsumduction; of the upper pole of one cornea, cycloduction; of the upper pole of one cornea outward, excycloduction; of the upper pole of one cornea inward, incycloduction. [L. duco, to lead] forced d. a maneuver to determine whether a mechanical obstruction is present in the eye; with forceps grasping an eye muscle, an attempt is made to passively move the eyeball in the direction of restricted rotation. SYN: passive d.. passive d. SYN: forced d..

ductless (dukt′les)
Having no duct; denoting certain glands having only an internal secretion.

ductular (duk′too-lar)
Relating to a ductule.

ductule (duk′tool)
A minute duct. SYN: ductulus. aberrant ductules [TA] the superior or inferior diverticula of the epididymis. SYN: ductuli aberrantes [TA] , aberrant ducts, ductus aberrantes, vasa aberrantia. biliary ductules the excretory ducts of the liver that connect the interlobular ductules to the right (or left) hepatic duct. SYN: canalicular ducts (2) , ductuli biliferi, ductus biliferi, tubuli biliferi. efferent ductules of testis [TA] 12–14 small seminal ducts leading from the testis to the head of the epididymis. SYN: ductuli efferentes testis [TA] , efferent duct, vas efferens (3) . excretory ductules of lacrimal gland SYN: excretory ducts of lacrimal gland, under duct. inferior aberrant d. [TA] a narrow, coiled tubule frequently connected to the first part of the ductus deferens or to the lower part of the ductus epididymitis. SYN: ductulus aberrans inferior [TA] , Haller vas aberrans. interlobular ductules bile ductules occupying portal canals between hepatic lobules that open into the ductuli biliferi. SYN: ductuli interlobulares. prostatic ductules [TA] about 20 minute canals that receive the prostatic secretion from the glandular tubules and discharge it through openings on either side of the urethral crest in the posterior wall of the urethra. SYN: ductuli prostatici [TA] , ductus prostatici, prostatic ducts. superior aberrant d. [TA] a diverticulum from the head of the epididymis. SYN: ductulus aberrans superior [TA] . transverse ductules of epoöphoron [TA] a series of 10–15 short tubules that open into the longitudinal duct of the epoöphoron and represent vestiges of the mesonephric duct. SYN: ductuli transversi epoöphori [TA] , tubuli epoöphori.

ductulus, pl .ductuli (duk′too-lus, -too-li)
SYN: ductule. [Mod. L. dim. of L. ductus, duct] d. aberrans inferior [TA] SYN: inferior aberrant ductule. d. aberrans superior [TA] SYN: superior aberrant ductule. ductuli aberrantes [TA] SYN: aberrant ductules, under ductule. d. alveolaris, pl .ductuli alveolares SYN: alveolar duct. ductuli biliferi SYN: biliary ductules, under ductule. ductuli efferentes testis [TA] SYN: efferent ductules of testis, under ductule. ductuli excretorii glandulae lacrimalis SYN: excretory ducts of lacrimal gland, under duct. ductuli interlobulares SYN: interlobular ductules, under ductule. ductuli paroöphori tubular remnants of the embryonic mesonephros forming the paroöphoron. SYN: tubuli paroöphori. ductuli prostatici [TA] SYN: prostatic ductules, under ductule. ductuli transversi epoöphori [TA] SYN: transverse ductules of epoöphoron, under ductule. SEE ALSO: epoophoron.

ductus, gen. and pl. ductus (duk′tus) [TA]
SYN: duct. [L. a leading, fr. duco, pp. d., to lead] d. aberrantes SYN: aberrant ductules, under ductule. d. arteriosus a fetal vessel connecting the left pulmonary artery with the descending aorta; in the first two months after birth, it normally changes into a fibrous cord, the ligamentum arteriosum; persistent postnatal patentcy is a correctable cardiovascular handicap. SYN: arterial canal, arterial duct, Botallo duct. d. biliaris [TA] SYN: bile duct (2) . d. biliferi SYN: biliary ductules, under ductule. d. caroticus a portion of the embryonic dorsal aorta between points of juncture with the third and fourth arch arteries; it disappears early in development. SYN: carotid duct. d. choledochus [TA] SYN: bile duct (1) . d. cochlearis [TA] SYN: cochlear duct. d. cysticus [TA] SYN: cystic duct. d. deferens [TA] the secretory duct of the testicle, running from the epididymis, of which it is the continuation, to the prostatic urethra where it terminates as the ejaculatory duct. SYN: deferent canal, deferent duct, spermatic duct, spermiduct (1) , testicular duct, vas deferens. d. deferens vestigialis SYN: longitudinal duct of epoöphoron. d. diverticulum SYN: ductal aneurysm. d. dorsopancreaticus SYN: accessory pancreatic duct. d. ejaculatorius [TA] SYN: ejaculatory duct. d. endolymphaticus [TA] SYN: endolymphatic duct. d. epididymidis [TA] SYN: duct of epididymis. d. excretorius SYN: excretory duct. d. excretorius glandulae vesiculosae [TA] d. excretorius vesiculae seminalis [TA] SYN: excretory duct of seminal gland. d. glandulae bulbourethralis [TA] SYN: duct of bulbourethral gland. d. hemithoracicus SYN: hemithoracic duct. d. hepaticus communis [TA] SYN: common hepatic duct. d. hepaticus dexter [TA] SYN: right hepatic duct. d. hepaticus sinister [TA] SYN: left hepatic duct. d. incisivus [TA] SYN: incisive duct. d. lactiferi [TA] SYN: lactiferous ducts, under duct. d. lingualis a pit on the upper surface of the tongue at the apex of the sulcus terminalis; it marks the point of origin of the d. thyroglossus of the embryo; known more commonly as the foramen cecum. d. lobi caudati dexter hepatis [TA] SYN: right duct of caudate lobe of liver. d. lobi caudati sinister hepatis [TA] SYN: left duct of caudate lobe of liver. d. longitudinalis epoöphori [TA] SYN: longitudinal duct of epoöphoron. SEE ALSO: epoophoron. d. lymphaticus dexter [TA] SYN: right lymphatic duct. d. mesonephricus SYN: mesonephric duct. SEE ALSO: longitudinal duct of epoöphoron. d. nasolacrimalis [TA] SYN: nasolacrimal duct. d. pancreaticus [TA] SYN: pancreatic duct. d. pancreaticus accessorius [TA] SYN: accessory pancreatic duct. d. paramesonephricus SYN: paramesonephric duct. d. paraurethrales [TA] SYN: paraurethral ducts, under duct. d. parotideus [TA] SYN: parotid duct. patent d. arteriosus d. arteriosus. d. perilymphaticus SYN: cochlear aqueduct. d. pharyngobranchialis III a narrow communication between the third branchial pouch and the pharynx in the embryo. d. pharyngobranchialis IV a narrow communication between the fourth branchial pouch and the pharynx in the embryo. d. prostatici SYN: prostatic ductules, under ductule. d. reuniens [TA] a short membranous tube passing from the lower end of the saccule to the cochlear duct of the membranous labyrinth. SYN: canaliculus reuniens, canalis reuniens, Hensen canal, Hensen duct, uniting canal, uniting duct. d. saccularis [TA] SYN: saccular duct. d. semicirculares [TA] SYN: semicircular ducts, under duct. d. sublinguales minores [TA] SYN: minor sublingual ducts, under duct. d. sublingualis major [TA] SYN: major sublingual duct. d. submandibularis [TA] SYN: submandibular duct. d. submaxillaris SYN: submandibular duct. d. sudoriferus SYN: duct of sweat glands. d. thoracicus [TA] SYN: thoracic duct. d. thoracicus dexter right lymphatic duct. d. thyroglossus [TA] SYN: thyroglossal duct. d. utricularis [TA] SYN: utricular duct. d. utriculosaccularis [TA] SYN: utriculosaccular duct. d. venosus in the fetus, continuation of the left umbilical vein through the liver to the vena cava inferior; after birth, its lumen becomes obliterated, forming the ligamentum venosum. d. venosus arantii rarely used term for d. venosus.

Benedict, 18th century British oculist. See D. membrane.

Duffy blood group
See Blood Groups appendix.

Louis A., U.S. physician, 1806–1884.

Louis A., U.S. dermatologist, 1845–1913. See D. disease.

Alfred, German obstetrician-gynecologist, 1862–1933. See D. incisions, under incision.

William Waddell D., U.S. pathologist, 1883–1945. See D. bleeding time test.

Clement, English physician, 1845–1925. See D. disease, Filatov-D. disease.

Cuthbert E., British pathologist, 1890–1977. See D. classification.

dulcin (dul′sin)
Has been used as a substitute for sugar, being 200 times as sweet as cane sugar. Because of hydrolysis to aminophenol, it may produce an injurious effect when used over long periods of time.

dulcite, dulcitol, dulcose (dul′sit, -si′tol, -kos)

dull (dul)
Not sharp or acute, in any sense; qualifying a surgical instrument, the action of the mind, pain, a sound (especially the percussion note), etc. [M.E. dul]

dullness, dulness (dul′nes)
The character of the sound obtained by percussing over a solid part incapable of resonating; usually applied to an area containing less air than those which can resonate. shifting d. a sign of free peritoneal fluid wherein the d. of percussion shifts, generally from one side to the other, as the patient is turned from side to side.

Pierre L., French chemist, 1785–1838. See D.-Petit law.

dummy (dum′e)
SYN: pontic.

Alphonse, French physician, 1827–1899. See D. pessary.

dumping (dump′ing)
See d. syndrome.

James M., Scottish gynecologist, 1826–1890. See D. folds, under fold, D. mechanism, D. placenta, D. ventricle.

Surname of first studied patients afflicted with what is now known as D. disease.

Richard L. See Lison-D. stain.

duocrinin (doo-o-krin′in)
A postulated gastrointestinal hormone that is liberated by the contact of gastric contents with the intestine and that stimulates the secretory activity of the duodenal glands (Brunner glands). [duodenum + G. krino, to secrete, + -in]

duodenal (doo′o-de′nal, doo-od′e-nal)
Relating to the duodenum.

duodenectomy (doo-o-de-nek′to-me)
Excision of the duodenum. [duodenum + G. ektome, excision]

duodenitis (doo-od-e-ni′tis)
Inflammation of the duodenum.

Combining form relating to the duodenum. [L. duodenum, scil., digitorum breadth of 12 fingers]

duodenocholangitis (doo-o-de′no-ko-lan-ji′tis)
Inflammation of the duodenum and common bile duct. [duodeno- + G. chole, bile, + angeion, vessel, + -itis, inflammation]

duodenocholecystostomy (doo-o-de′no-ko-le-sis-tos′to-me)
SYN: cholecystoduodenostomy. [duodeno- + G. chole, bile, + kystis, bladder, + stoma, mouth]

duodenocholedochotomy (doo-o-de′no-ko-led-o-kot′o-me)
Incision into the common bile duct and the adjacent portion of the duodenum. [duodeno- + G. cholèdochus, bile duct, + tome, incision]

duodenocystostomy (doo-o-de′no-sis-tos′to-me)
1. SYN: cholecystoduodenostomy. 2. SYN: cystoduodenostomy. 3. SYN: pancreatic cystoduodenostomy.

duodenoenterostomy (doo-o-de′no-en-ter-os′to-me)
Establishment of communication between the duodenum and another part of the intestinal tract. [duodeno- + G. enteron, intestine, + stoma, mouth]

duodenojejunostomy (doo-o-de′no-je-joo-nos′to-me)
Operative formation of an artificial communication between the duodenum and the jejunum. [duodeno- + jejunum, + G. stoma, mouth]

duodenolysis (doo-o-de-nol′i-sis)
Incision of adhesions to the duodenum. [duodeno- + G. lysis, a freeing]

duodenorrhaphy (doo-o-de-nor′a-fe)
Suture of a tear or incision in the duodenum. [duodeno- + G. rhaphe, a seam]

duodenoscopy (doo-o-de-nos′ko-pe)
Inspection of the interior of the duodenum through an endoscope. [duodeno- + G. skopeo, to examine]

duodenostomy (doo-o-de-nos′to-me)
Establishment of a fistula into the duodenum. [duodeno- + G. stoma, mouth]

duodenotomy (doo-o-de-not′o-me)
Incision of the duodenum. [duodeno- + G. tome, incision]

duodenum, gen. duodeni, pl .duodena (doo-o-de′num, doo-od′e-num; -od′e-na, -de′na) [TA]
The first division of the small intestine, about 25 cm or 12 fingerbreadths (hence the name) in length, extending from the pylorus to the junction with the jejunum at the level of the first or second lumbar vertebra on the left side. It is divided into the superior part, the first part of which is the duodenal cap, the descending part, into which the bile and pancreatic ducts open, the horizontal (inferior) part and the ascending part, terminating at the duodenojejunal junction. [Mediev. L. fr. L. duodeni, twelve]

duovirus (doo′o-vi′rus)
SYN: rotavirus.

duplex (doo′pleks)
Providing two functions. See d. ultrasonography.

duplication (doo-pli-ka′shun)
1. A doubling. SEE ALSO: reduplication. 2. Inclusion of two copies of the same genetic material in a genome; an important step in diversification of genomes, as in the evolution of the (nonallelic) hemoglobin chains from a common ancestor. SYN: gene d.. [L. duplicatio, a doubling, fr. duplico, to double] d. of chromosomes a chromosome aberration resulting from unequal crossing over or exchange of segments between two homologous chromosomes; one chromosome of the pair loses a small segment, while the other gains this segment; the chromosome gaining the segment has undergone d. while its homologue has undergone deletion. See hemoglobin Lepore. gene d. SYN: d. (2) .

duplicitas (doo-plis′i-tahs)
Doubling of a part. [L. a doubling, fr. duplex (duplic-), two-fold] d. anterior conjoined twins in which there are two thoraces and two heads and a single pelvis with one pair of lower extremities. See conjoined twins, under twin. SEE ALSO: cephalodidymus, ileadelphus, iliadelphus. SYN: catadidymus. d. posterior conjoined twins in which there is a single head and upper body and duplicated buttocks and legs. See conjoined twins, under twin. SEE ALSO: dipygus. SYN: anadidymus, ileadelphus, iliadelphus.

17th Century Paris surgeon and anatomist. See Dupré muscle.

Baron Guillaume, French surgeon and surgical pathologist, 1777–1835. See D. amputation, D. canal, D. contracture, D. disease of the foot, D. fascia, D. fracture, D. hydrocele, D. sign, D. suture, D. tourniquet.

dura (doo′ra) [TA]
SYN: d. mater. [L. fem. of durus, hard] d. mater cranialis [TA] SYN: cranial d. mater.

duraencephalosynangiosis (door′a-en-sef′a-lo-sin-anj-e- o′sis)
Surgical transposition of the superficial temporal artery with attached galea to the underlying dura with hope for cerebral revascularization; most commonly used in moyamoya syndrome. SYN: encephaloduroarteriosynangiosis.

dural (doo′ral)
Relating to the dura mater. SYN: duramatral.

dura mater (doo′ra ma′ter) [TA]
Pachymeninx (as distinguished from leptomeninx, the combined pia mater and arachnoid); a tough, fibrous membrane forming the outer covering of the central nervous system. SYN: dura [TA] , pachymeninx [TA] . [L. hard mother, mistransl. of Ar. umm al-jafiyah, tough protector or covering] d. of brain SYN: cranial d.. cranial d. [TA] the intracranial d., consisting of two layers: the outer periosteal layer that normally always adheres to the periosteum of the bones of the cranial vault; and the inner meningeal layer that in most places is fused with the outer. The two layers separate to accommodate meningeal vessels and large venous (dural) sinuses. The meningeal layer is also involved in the formation of the various dural folds, such as the falx cerebri and tentorium cerebelli and is comparable to and continuous with the dural mater of the spinal cord. The cranial epidural space is then an artifactual space between the bone and the combined periosteum/periosteal layer of the d. realized only as a result of pathologic or traumatic processes and is neither continuous with or comparable to the vertebral epidural space. SYN: dura mater cranialis [TA] , d. encephali&star, cerebral part of d., d. of brain. d. encephali cranial d.. spinal d. [TA] single-layered strong membrane, comparable to and continuous with (at foramen magnum) the meningeal layer of the intracranial d. of the brain. It does not (in contrast to the d. of brain) adhere to the enveloping bony structures (vertebrae) or their periosteum, being separated from the latter by a considerable space, the vertebral epidural space—a true space containing the internal vertebral venous plexus embedded in a matrix of epidural fat. SYN: d. spinalis [TA] , d. of spinal cord, endorrhachis, theca vertebralis. d. of spinal cord SYN: spinal d.. d. spinalis [TA] SYN: spinal d..

duramatral (doo-ra-ma′tral)
SYN: dural.

Francisco, U.S. bacteriologist, 1899–1958. See Duran-Reynals permeability factor.

duraplasty (doo′ra-plas-te)
A reconstructive operation on the open dura mater that involves a primary closure or secondary closure with another soft tissue material ( e.g., muscle, fascia, allograft dura). [dura (mater) + G. plastos, formed]

duration (D) (doo-ra′shun)
A continuous period of time. half amplitude pulse d. the time, in milliseconds, required for a wave form to reach half of its full magnitude. pulse wave d. the interval between onset of the leading edge and the end of the trailing edge of a pulse wave.

Hermann, German pathologist, 1869–1941. See D. nodes, under node.

dur. dolor.
Abbreviation for L. duarte dolare, while pain lasts.

Henri, French neurosurgeon, 1849–1921. See D. lesion, D. hemorrhage.

Arthur E., English surgeon, 1834–1895. See D. tube.

Paul L., French physician, 1826–1897. See D. disease, D. murmur, D. sign.

Acronym for diffuse unilateral subacute neuroretinitis.

Abbreviation for deoxyuridine 5-triphosphate.

Joseph Everett, English physician, 1877–1905. See D. disease, D. relapsing fever.

Guichaud Joseph, French anatomist, 1648–1730. See D. fissures, under fissure, D. gland, D. muscle.

dwarf (dworf)
An abnormally undersized person with disproportion among the bodily parts. See dwarfism. [A.S. dweorh] hypophysial d. dwarfism as result of failure of growth hormone production because of hypothalamic or pituitary abnormality. SYN: pituitary d.. hypothyroid d. dwarfism associated with lack of thyroid function. pituitary d. SYN: hypophysial d..


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