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Medical Dictionary - Dictionary of Medicine and Human Biology


Medical Dictionary


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roll (rol)
1. A mass or structure in the shape of a r.. 2. The process by which a round entity is moved by a pressure gradient, as a leukocyte moves along a blood vessel wall. iliac r. a sausage-shaped, often painful, nonfluctuating mass, with convexity to the right, palpable in the left iliac fossa, due to induration of the walls of the sigmoid flexure. scleral r. SYN: scleral spur.

Roller
Christian F.W., German neurologist and psychiatrist, 1844–1978. See R. nucleus.

roller (ro′ler)
See r. bandage.

Rolleston
Sir Humphry D., British physician, 1862–1944. See R. rule.

Rollet
Alexander, Austrian physiologist, 1834–1903. See R. stroma, Ritter-R. phenomenon.

Romaña
Cecilio, Argentinian physician in Brazil, *1899. See R. sign.

Romano
C., 20th century Italian physician. See R.-Ward syndrome.

Romanowsky
Dimitri L., Russian physician, 1861–1921. See R. blood stain.

Romberg
Moritz H., German physician, 1795–1873. See R. test, R. disease, facial hemiatrophy of R., R. syndrome, R. sign.

rombergism (rom′berg-izm)
SYN: Romberg sign.

Römer
Paul H., German bacteriologist, 1876–1916. See R. test.

rongeur (rawn-zher′)
A strong biting forceps for nipping away bone. [Fr. ronger, to gnaw]

R&slash;onne
Henning K.T., Danish ophthalmologist, 1878–1947. See R. nasal step.

roof (roof)
A covering or rooflike structure; e.g., a tectorium, tectum, tegmen, tegmentum, integument. [A.S. hrof] r. of fourth ventricle [TA] SYN: tegmen ventriculi quarti. r. of mouth SYN: palate. r. of orbit [TA] formed by the orbital plate of the frontal bone and the lesser wing of the sphenoid bone, the optic canal opens at its posterior limit; an indentation, the fossa for the lacrimal gland, is located in the anterolateral part of the r.. SYN: paries superior orbitae [TA] , superior wall of orbit. r. of skull SYN: calvaria. r. of tympanic cavity SYN: tegmental wall of tympanic cavity. r. of tympanum SYN: tegmen tympani.

roofplate (roof′plat)
See roof plate.

rooming-in (room′ing-in)
Placement of newborn with mother, rather than in nursery, during the postpartum hospital stay.

root (root) [TA]
1. The primary or beginning portion of any part, as of a nerve at its origin from the brainstem or spinal cord. SYN: radix (1) [TA] . 2. SYN: r. of tooth. 3. The descending underground portion of a plant; it absorbs water and nutrients, provides support, and stores nutrients. For roots of pharmacologic significance not listed below, see specific names. [A.S. rot] accessory r. of tooth [TA] an anomalous additional tooth r.. SYN: radix accessoria [TA] . anatomical r. that portion of a tooth extending from the cervical line to its apical extremity. anterior r. of spinal nerve [TA] the motor r. of a spinal nerve. SYN: radix anterior nervi spinalis [TA] , motor r. of spinal nerve&star, radix motoria nervi spinalis&star, ventral r. of spinal nerve&star, radix ventralis nervi spinalis. buccal r. of tooth [TA] r. of a multirooted tooth which is located toward the buccal side of the alveolar ridge. SYN: radix buccalis [TA] . clinical r. of tooth [TA] that portion of a tooth embedded in the investing structures; the portion of a tooth not visible in the oral cavity. SYN: radix clinica dentis [TA] . cochlear r. of VIII nerve one of the components of the vestibulocochlear nerve; it is made up of the central processes of the bipolar neurons that compose the spiral (cochlear) ganglion in the spiral canal of the modiolus of the bony cochlea; the cochlear r. enters the cranial cavity by passing in fascicles through the spiral foraminous tract at the bottom of the internal auditory meatus; it enters the brainstem through the pontomedullary groove, closely adhering to the caudoventral aspect of the vestibular r., and distributes its fibers to the ventral and dorsal cochlear nuclei in the floor of the lateral recess of the fourth ventricle. SYN: radix inferior nervi vestibulocochlearis. cranial r. of accessory nerve [TA] the roots of the accessory nerve that arise from the medulla; the nerve fibers of the cranial r. join the intracranial portion of the vagus nerve and are distributed to the pharyngeal plexus, providing the motor innervation of the soft palate (except the tensor veli palati) and the pharynx. SEE ALSO: accessory nerve [CN XI]. SYN: radix cranialis nervi accessorii [TA] , pars vagalis nervi accessorii&star, vagal part of accessory nerve&star, accessory portion of spinal accessory nerve. Culver r. SYN: leptandra. dorsal r. of spinal nerve posterior r. of spinal nerve. facial r. SYN: nerve of pterygoid canal. r. of facial nerve fibers running from the facial motor nucleus upward to the facial colliculus where they curve around the abducens nucleus and then pass peripherally between the superior olive and sensory nucleus of the trigeminal, to emerge as the facial nerve from the pontomedullary groove. SYN: radix nervi facialis. r. of foot SYN: tarsus (1) . hair r. the part of a hair that is embedded in the hair follicle, its lower succulent extremity capping the dermal papilla pili in the deep bulbous portion of the follicle. SYN: radix pili. inferior r. of ansa cervicalis [TA] fibers from the second and third cervical nerves that pass forward and downward along the internal jugular vein; they contribute to the ansa cervicalis and innervate the infrahyoid muscles. SYN: radix inferior ansae cervicalis [TA] , inferior limb of ansa cervicalis&star, descendens cervicalis. lateral r. of median nerve [TA] the part of the median nerve arising from the lateral cord of the brachial plexus. SYN: radix lateralis nervi mediani [TA] . lateral r. of optic tract [TA] the larger division of the posterior end of the optic tract that terminates in the lateral geniculate body. SYN: radix lateralis tractus optici [TA] . long r. of ciliary ganglion SYN: sensory r. of ciliary ganglion. r. of lung [TA] all the structures entering or leaving the lung at the hilum, forming a pedicle invested with the pleura; includes the bronchi, pulmonary artery and veins, bronchial arteries and veins, lymphatics, and nerves. SYN: radix pulmonis [TA] . May apple r. SYN: podophyllum resin. medial r. of median nerve [TA] the part of the median nerve coming from the medial cord of the brachial plexus. SYN: radix medialis nervi mediani [TA] . medial r. of optic tract [TA] the smaller division of the posterior end of the optic tract that disappears under the medial geniculate body. SYN: radix medialis tractus optici [TA] . r. of mesentery [TA] the origin of the mesentery of the small intestine (jejunum and ileum) from the posterior parietal peritoneum; about 9 inches (23 cm) in length, it extends from the duodenojejunal flexure (just to the left of the midline at the L2 vertebral level) to the ileocecal junction (iliac fossa). SYN: radix mesenterii [TA] . motor r. of ciliary ganglion SYN: parasympathetic r. of ciliary ganglion. motor r. of spinal nerve anterior r. of spinal nerve. motor r. of trigeminal nerve [TA] the smaller r. of the trigeminal nerve, composed of fibers originating from the trigeminal motor nucleus and emerging from the pons medial to the much larger sensory r., to join the mandibular nerve; it carries motor and proprioceptive fibers to the muscles derived from the first bronchial (mandibular) arch, including the four muscles of mastication, plus the mylohyoid, anterior belly of the digastric, and the tensores tympani and veli palati. SYN: radix motoria nervi trigemini [TA] , masticator nerve, portio minor nervi trigemini. r. of nail the proximal end of the nail, concealed under a fold of skin. SYN: radix unguis. nasociliary r. of ciliary ganglion sensory r. of ciliary ganglion. nerve r. one of the two bundles of nerve fibers (posterior and anterior roots) emerging from the spinal cord that join to form a single segmental (mixed) spinal nerve; some of the cranial nerves are similarly formed by the union of two roots, in particular the fifth or trigeminal nerve. r. of nose [TA] the upper least protruding portion of the external nose situated between the two orbits. SYN: radix nasi [TA] . oculomotor r. of ciliary ganglion parasympathetic r. of ciliary ganglion. olfactory roots SYN: olfactory striae, under stria. roots of olfactory tract, lateral and medial the two fiber bands that form the caudal continuation of the olfactory tract that, upon diverging, enclose the olfactory tubercle. parasympathetic r. of ciliary ganglion [TA] a branch of the oculomotor nerve supplying parasympathetic preganglionic nerve fibers to the ciliary ganglion. SYN: radix parasympathica ganglii ciliaris [TA] , oculomotor r. of ciliary ganglion&star, radix nervi oculomotorii ad ganglion ciliare&star, radix oculomotoria ganglii ciliaris&star, branch of oculomotor nerve to ciliary ganglion, motor r. of ciliary ganglion, radix brevis ganglii ciliaris, short r. of ciliary ganglion. parasympathetic r. of otic ganglion lesser petrosal nerve. parasympathetic r. of pelvic ganglia pelvic splanchnic nerves, under nerve. parasympathetic r. of pterygopalatine ganglion greater petrosal nerve. parasympathetic r. of submandibular ganglion SYN: chorda tympani. r. of penis [TA] the proximal attached part of the penis, including the two crura and the bulb. SYN: radix penis [TA] . posterior r. of spinal nerve [TA] the sensory r. of a spinal nerve, having a dorsal r. ganglion containing the nerve cell bodies of the fibers conveyed by the r. in its distal end. SYN: radix posterior nervi spinalis [TA] , dorsal r. of spinal nerve&star, radix sensoria nervi spinalis&star, sensory r. of spinal nerve&star, radix dorsalis nervi spinalis. sensory r. of ciliary ganglion [TA] sensory fibers passing from the eyeball through the ciliary ganglion to their cell bodies in the trigeminal ganglion via the nasociliary nerve. SYN: radix sensoria ganglii ciliaris [TA] , nasociliary r. of ciliary ganglion&star, radix nasociliaris ganglii ciliaris&star, ramus communicans nervi nasociliaris cum ganglio ciliari&star, communicating branch of nasociliary nerve with ciliary ganglion, long r. of ciliary ganglion, radix longa ganglii ciliaris. sensory r. of pterygopalatine ganglion [TA] the ganglionic branches, two short sensory branches of the maxillary nerve in the pterygopalatine fossa, the fibers of which pass through the pterygopalatine ganglion without synapse. SYN: radix sensoria ganglii pterygopalatini [TA] , ganglionic branches of maxillary nerve to pterygopalatine ganglion&star, rami ganglionici nervi maxillaris&star, ganglionic branches of maxillary nerve, nervi pterygopalatini, nervi sphenopalatini, pterygopalatine nerves, rami ganglionares. sensory r. of spinal nerve posterior r. of spinal nerve. sensory r. of sublingual ganglion [TA] branch or branches of the lingual nerve conveying sensory fibers to the sublingual ganglion that traverse the ganglion without synapse for distribution to the floor of the mouth. SYN: radix sensoria ganglii sublingualis [TA] , ganglionic branches of lingual nerve to sublingual ganglion&star, ganglionic branches of lingual nerve to submandibular ganglion&star, rami communicantes ganglii sublingualis cum nervo linguali&star. sensory r. of submandibular ganglion [TA] motor roots of submandibular ganglion; communicating branches between submandibular ganglion and lingual nerve. SYN: radix sensoria ganglii submandibularis [TA] , rami communicantes ganglii submandibularis cum nervo linguali&star, ganglionic branches of lingual nerve. sensory r. of trigeminal nerve [TA] the large sensory r. of the trigeminal (or fifth cranial) nerve, extending from the semilunar ganglion into the pons through the middle cerebellar peduncle or brachium pontis, immediately lateral to the small motor r.. SYN: radix sensoria nervi trigemini [TA] , portio major nervi trigemini. short r. of ciliary ganglion SYN: parasympathetic r. of ciliary ganglion. spinal r. of accessory nerve [TA] originates from the upper five or six cervical spinal segments, emerges from the lateral surface of the spinal cord and ascends through the foramen magnum to join the cranial r.. SYN: radix spinalis nervi accessorii [TA] , pars spinalis nervi accessorii&star, spinal part of accessory nerve&star. superior r. of ansa cervicalis [TA] the fibers that arise from the first and second cervical nerves, accompany the hypoglossal nerve, then branch off to meet the inferior r. in the ansa cervicalis; they innervate the infrahyoid muscles. SYN: radix superior ansae cervicalis [TA] , superior limb of ansa cervicalis&star, descendens hypoglossi, descending branch of hypoglossal nerve. sympathetic r. of ciliary ganglion [TA] postganglionic fibers, having cell bodies in the superior cervical ganglion, branching from the carotid plexus passing through the ciliary ganglion without synapse to reach the eyeball. SYN: radix sympathica ganglii ciliaris [TA] . sympathetic r. of otic ganglion [TA] branch arising from the periarterial plexus of the middle meningeal artery, bringing postsynaptic sympathetic fibers from the superior cervical sympathetic ganglion that traverse the ganglion without synapse for distribution to blood vessels within the parotid gland. SYN: radix sympathica ganglii otici [TA] . sympathetic r. of pterygopalatine ganglion deep petrosal nerve. sympathetic r. of sublingual ganglion [TA] branch arising from the periarterial plexus of the facial artery, bringing postsynaptic sympathetic fibers from the superior cervical sympathetic ganglion that traverse the ganglion without synapse for distribution to blood vessels of the sublingual gland. SYN: radix sympathica ganglii sublingualis [TA] . sympathetic r. of submandibular ganglion [TA] branch to the submandibular ganglion composed of postsynaptic sympathetic fibers from the internal carotid plexus conveyed largely by a periarterial plexus of the facial artery. SYN: radix sympathica ganglii submandibularis [TA] , ramus sympathicus (sympatheticus) ad ganglion submandibulare, sympathetic branch to submandibular ganglion. tegmental r. of tympanic cavity tegmental wall of tympanic cavity. r. of tongue [TA] the posterior attached portion of the tongue. SYN: radix linguae [TA] , base of tongue. r. of tooth [TA] that part of a tooth below the neck, covered by cementum rather than enamel, and attached by the periodontal ligament to the alveolar bone. SYN: radix dentis [TA] , radix (2) [TA] , r. (2) [TA] . roots of trigeminal nerve collective term for the sensory r. of trigeminal nerve and motor r. of trigeminal nerve. SYN: radices nervi trigemini. tuberous r. a r. that is swollen for food storage; tuberous primary roots occur in aconite, beet, and carrot; tuberous secondary roots occur in plants of the Umbelliferae; and tuberous adventitious roots occur in jalap and sweet potato. ventral r. of spinal nerve anterior r. of spinal nerve. vestibular r. vestibular r. of VIII nerve, a collective term for those sensory fibers of the 8th cranial nerve (vestibulocochlear) that originate from the vestibular labyrinth, have their cell bodies of origin in the vestibular ganglion, and function in the sphere of balance and equilibrium; centrally these fibers end primarily in the vestibular nuclei of the brainstem and in the cerebellum. SYN: radix superior nervi vestibulocochlearis, radix vestibularis, vestibular r. of vestibulocochlear nerve. vestibular r. of vestibulocochlear nerve SYN: vestibular r..

rootlets (root′lets)
In neuroanatomy, nerve r. (radicular fila). See filum. SEE ALSO: radicular fila, under filum.

root planing (plan′ing)
In dentistry, abrading of rough root surfaces to achieve a smooth surface.

ROP
Abbreviation for right occipitoposterior position.

ropalocytosis (ro-pal′o-si-to′sis)
Formation of numerous processes of erythroid cells, which in ultrathin sections appear club-shaped, associated with cytoplasmic vesicles and found in some diseases of the blood. [G. ropalon, club, + kytos, cell, + -osis, condition]

Ropes test
See under test.

Rorschach
Hermann, Swiss psychiatrist, 1884–1922. See R. test.

Rosa (ro′za)
A genus of plants including the roses (family Rosaceae); several varieties are the sources of rose oil: R. alba, cottage rose; R. centifolia, the pale rose or cabbage rose (source of official rose oil); R. damascena, damask rose; and R. gallica, red rose or French rose. [L. rose]

rosacea (ro-za′she-a)
Chronic vascular and follicular dilation involving the nose and contiguous portions of the cheeks; may vary from mild but persistent erythema to extensive hyperplasia of the sebaceous glands, seen especially in men as rhinophyma and by deep-seated papules and pustules; accompanied by telangiectasia at the affected erythematous sites. SYN: acne r.. [L. rosaceus, rosy] granulomatous r. papular lesions in r., characterized microscopically by perifollicular granulomas with central necrosis and scattered giant cells. Lupus miliaris disseminatus faciei is probably a form of granulomatous r.. SYN: r.-like tuberculid, tuberculoid r.. hypertrophic r. SYN: rhinophyma. tuberculoid r. SYN: granulomatous r..

Rosai
Juan, U.S. pathologist, b. 1941. See R.-Dorfman disease.

rosanilin (ro-zan′i-lin) [C.I. 42510]
A tris(aminophenyl)methyl compound; together with pararosanilin it is a component of basic fuchsin; also used as an antifungal agent.

rosaprostol (ro′sa-prost-ol)
A prostaglandin analog with protective properties for the gastric mucosa; similar to misoprostol and also used as an antiulcerative drug.

rosary (ro′zer-e)
A beadlike arrangement or structure. rachitic r. a row of beading at the junction of the ribs with their cartilages, often seen in rachitic children. SYN: beading of the ribs.

Roscoe
Sir Henry E., British chemist, 1833–1915. See Bunsen-R. law.

Rose
Edmund, German physician, 1836–1914. See R. position.

Rose
Harry M., U.S. microbiologist, *1906. See R.-Waaler test.

rose (roz)
1. Any shrub of the genus Rosa. 2. The petals of Rosa gallica, collected before expanding; used for its agreeable odor. [L. rosa] r. hips the fruit or berries from wild r. bushes and in particular Rosa canina, R. gallica, R. condita, and R. Rugosa, (family Rosaceae). A rich source of vitamin C (ascorbic acid). SYN: hipberries. r. oil a volatile oil from Rosa centifolia; used in perfumery and in ointments. SYN: attar of r..

rose bengal (roz′ ben′gal) [C.I. 45440]
The sodium salt of tetraiodotetra-chlorfluorescein, used as a stain for bacteria, as a stain in the diagnosis of keratitis sicca, and in liver function tests.

Rose-Bradford kidney
See under kidney.

rosemary oil (roz′mar-e)
The volatile oil distilled with steam from the fresh flowering tops of Rosmarinus officinalis (family Labiatae); used as a flavoring and in perfumery.

Rosenbach
Ottomar, German physician, 1851–1907. See R. law, R. sign, R. test, R.-Gmelin test.

Rosenmüller
Johann C., German anatomist, 1771–1820. See R. fossa, R. gland, R. node, R. recess, R. valve, organ of R..

Rosenthal
Curt, 20th century German psychiatrist. See Melkersson-R. syndrome.

Rosenthal
Friedrich C., German anatomist, 1780–1829. See R. canal, R. vein, basal vein of R..

Rosenthaler-Turk reagent
See under reagent.

Rosenthal fiber
See under fiber.

roseola (ro-ze′o′la)
A symmetrical eruption of small, closely aggregated patches of rose-red color. It is believed to be caused by human herpesvirus type 6. SEE ALSO: exanthema subitum. SYN: macular erythema. [Mod. L. dim. of L. roseus, rosy] epidemic r. SYN: rubella. idiopathic r. r. not occurring as a symptom of a recognized general disease. r. infantilis, r. infantum SYN: exanthema subitum. syphilitic r. usually the first eruption of syphilis, occurring 6 to 12 weeks after the initial lesion.

Roser
Wilhelm, German surgeon, 1817–1888. See R.-Nélaton line.

rosette (ro-zet′)
1. The quartan malarial parasite Plasmodium malariae in its segmented or mature phase. 2. A grouping of cells characteristic of neoplasms of neuroblastic, neuroectodermal, or ependymal origin; a number of nuclei form a ring from which neurofibrils, which can be demonstrated by silver impregnation, extend to interlace in the center (Homer-Wright r.). 3. Roselike coiling of the uterus among certain pseudophyllidean tapeworms, such as Diphyllobothrium latum. 4. Cells of one type surrounding a cell of another type. [Fr. a little rose] E r. (ro-zet′) the adherence of erythrocytes to cells. Sheep erythrocytes will adhere spontaneously to human T cells, forming rosettes. EAC r. indicates the presence of complement receptors. Erythrocytes (E) coated with antibody (A) and complement (C) are incubated with test cells; if the test cells have complement receptors, the EAC will adhere to these cells, forming rosettes. Homer-Wright rosettes pseudorosettes formed by the arrangement of tumor cells around an area of fibrillarity, evidence of neuroblastic differentiation in a medulloblastoma or primitive neuroectodermal tumor. Wintersteiner rosettes rosettes found only in retinal embryonic tumors, formed by a group of columnar cells with a peripheral basement membrane arranged in a radial manner around a central cavity, the spokes corresponding to the photoreceptors.

rosin (roz′in)
The solid resin obtained after steam distillation of crude balsam from Pinus palustris and from other species of Pinus (family Pinaceae); used in plasters to render them adhesive and also in ointments to render them locally stimulating. SYN: colophony, resin (2) .

Ross
Donald N., Br. cardiac surgeon, * 1922; introduced aortic valve replacement using a pulmonic valve autograft. See R. procedure.

Ross
Sir George W., Canadian physician, 1841–1931. See R.-Jones test.

Ross
Sir Ronald, English physician and Nobel laureate, 1857–1932. See R. cycle.

Rossolimo
Grigoriy I., Russian neurologist, 1860–1928. See R. reflex, R. sign.

rostellum (ros-tel′um)
The anterior fixed or invertible portion of the scolex of a tapeworm, frequently provided with a row (or several rows) of hooks. [L. dim. of rostrum, a beak] armed r. r. with one or more rows of hooks. unarmed r. r. lacking hooks.

rostrad (ros′trad)
1. In a direction toward any rostrum. 2. Situated nearer a rostrum or the snout end of an organism in relation to a specific reference point; opposite of caudad (2). [L. rostrum, beak, + -ad, toward]

rostral (ros′tral) [TA]
1. Relating to any rostrum or anatomic structure resembling a beak. 2. At the head end. SYN: rostralis [TA] . [L. rostralis, fr. rostrum, beak]

rostralis (ros′tra′lis) [TA]
SYN: rostral, rostral. [L. fr. rostrum, beak]

rostrate (ros′trat)
Having a beak or hook. [L. rostratus]

rostriform (ros′tri-form)
Beak-shaped. [L. rostrum, beak]

rostrum, pl .rostrarostrums (ros′trum, -tra) [TA]
Any beak-shaped structure. [L. a beak] r. corporis callosi [TA] SYN: r. of corpus callosum. r. of corpus callosum [TA] beak of the corpus callosum, the recurved portion of the corpus callosum passing backward from the genu to the anterior commissure. SYN: r. corporis callosi [TA] . sphenoidal r. [TA] the anterior projecting part of the body of the sphenoid bone that articulates with the vomer. SYN: r. sphenoidale [TA] , r. of the sphenoid bone. r. sphenoidale [TA] SYN: sphenoidal r.. r. of the sphenoid bone SYN: sphenoidal r..

ROT
Abbreviation for right occipitotransverse position.

rot
To decay or putrify. [A.S. rotian]

rotamase (ro′ta-maz)
Enzyme capable of altering the rotational conformation of a molecule.




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