|Medical Dictionary - Dictionary of Medicine and Human Biology|
Original trivial name for the saturated form of phorbol. [fr. Croton tiglium (Euphorbiaceae)]
tiglic acid (tig′lik)
An unsaturated fatty acid present in glycerides in croton oil.
An intermediate in the degradation of l-isoleucine. SYN: tiglyl-coenzyme A.
See chromophil substance. [G. tigroeides, fr. tigris, tiger, + eidos, appearance]
SYN: chromatolysis. [tigroid + G. lysis, dissolution]
Abbreviation for tumor-infiltrating lymphocytes, under lymphocyte.
Paul Jules, French surgeon, 1834–1904. See spiral of T..
A small synthetic molecule used to induce interferon in mice.
Abbreviation for tumor-infiltrating lymphocytes, under lymphocyte.
Slope. pantoscopic t. an oblique astigmatism caused by slanting a spherical lens so that light rays strike the lens at a nonperpendicular angle, altering the spherical and cylindrical refractive power of the lens.
timbre (tam′br, tim′br)
The distinguishing quality of a sound, by which one may determine its source, based principally on the distribution of overtones. SYN: tone color. [Fr.]
time (t) (tim)
1. That relation of events which is expressed by the terms past, present, and future, and measured by units such as minutes, hours, days, months, or years. 2. A certain period during which something definite or determined is done. SYN: tempus (2) . [A.S. tima] activated clotting t. (ACT) the most common test used for coagulation t. in cardiovascular surgery. activated partial thromboplastin t. (aPTT) the t. needed for plasma to form a fibrin clot following the addition of calcium and a phospholipid reagent; used to evaluate the intrinsic clotting system. AH conduction t. atrioventricular conduction. association t. t. elasping between a stimulus and the verbalized response to it. biologic t. the concept that our appreciation of t. varies with age and is governed by the neural organization of the individual; it obeys a logarithmic rather than an arithmetic law. bleeding t. the t. interval between the appearance of the first drop of blood and the removal of the last drop following puncture of the ear lobe or the finger, usually 1–3 min; it provides a global but imprecise evaluation of platelet and capillary function. circulation t. the t. taken for the blood to pass through a given circuit of the vascular system, e.g., the pulmonary or systemic circulation, from one arm to another, from arm to tongue, or from arm to lung; it is measured by the injection into an arm vein of a substance, such as sodium dehydrocholate, ether, fluorescein, histamine, or a radium salt, which can be detected when it arrives at another point in the vascular system. clot retraction t. the t. required for a blood clot to separate from the tube wall and express serum, usually completed in 18–24 hours, but retarded or absent in persons with thrombocytopenic purpura. clotting t. SYN: coagulation t.. coagulation t. the t. required for blood to coagulate. SYN: clotting t.. doubling t. the t. it takes for the number of cells in a neoplasm to double, with shorter doubling times implying more rapid growth. euglobulin clot lysis t. a measure of the ability of plasminogen activators and plasmin to lyse a clot; normally, clot lysis is determined by the balance of factors which activate fibrinolysis (plasminogen activators and plasmin) and those which inhibit lysis; in certain conditions ( e.g., carcinoma or hepatic insufficiency) activating factors predominate and can be measured by noting the t. it takes the euglobulin fraction of plasma (excluding inhibitors of fibrinolysis) to clot. fading t. the t. required for a constant stimulus applied to a fixed area of the peripheral visual field to stop. t. of flight the t. for a photon created by annihilation of a positron-electron pair to reach a detector; since annihilation photons are created in pairs and travel in opposite directions at about 3 × 1010 cm/sec, measurement of the difference in arrival t. at detectors with subnanosecond resolution allows calculation of the location of the event; the basic physics of positron emission tomography. forced expiratory t. (FET) the t. taken to expire a given volume or a given fraction of vital capacity during measurement of forced vital capacity; subscripts specify the exact parameters measured. half-t. half-t.. HR conduction t. intraventricular conduction. HV conduction t. intraventricular conduction. inertia t. the interval elapsing between the reception of the stimulus from a nerve and the contraction of the muscle. interatrial conduction t. SYN: intraatrial conduction t. (2) . intraatrial conduction t. 1. the total duration of electrical activity of the atria in one cardiac cycle; 2. the t. between right atrial and left atrial activation. SYN: interatrial conduction t.. left ventricular ejection t. (LVET) the t. measured clinically from onset to incisural notch of the carotid or other pulse; properly, the t. of ejection of blood from the left ventricle beginning with aortic valve opening and ending with aortic valve closure. PA conduction t. atrioventricular conduction. partial thromboplastin t. (PTT) activated partial thromboplastin t.. PH conduction t. atrioventricular conduction. prothrombin t. (PT) the t. required for clotting after thromboplastin and calcium are added in optimal amounts to blood of normal fibrinogen content; if prothrombin is diminished, the clotting t. increases; used to evaluate the extrinsic clotting system. SEE ALSO: prothrombin test. reaction t. the interval between the presentation of a stimulus and the responsive reaction to it. recognition t. the interval between the application of a stimulus and the recognition of its nature. relaxation t. (τ) the t. required for the substrate in an enzymatic or chemical reaction to fall to 1/e of its initial value. repetition t. (TR) in magnetic resonance imaging, the t. between repetitions of the pulse sequence. rise t. 1. the t. required for a pulse or echo to rise from onset to its peak amplitude; 2. the t. required for a pulse or echo to rise from 10–90% peak amplitude. running t. the t. during which an activity ( e.g., chromatography development) occurs. Russell's viper venom clotting t. a clotting t. determination performed on citrated platelet-poor plasma using Russell's viper venom as an activating agent. This allows activation of factor X directly without the need for other coagulation factors and is used to confirm factor X defects. SEE ALSO: Stypven t. test. sensation t. the minimal t. a visual image must be exposed in order to be perceived. sinoatrial conduction t. (SACT) the t. required for an impulse to travel from sinus node to atrium; estimated indirectly during reset nodus sinuatrialis period by halving the average interval from the premature beat to the following normal sinus beat of the atrium. sinoatrial recovery t. (SART) interval from the last paced P wave to the first succeeding spontaneous P wave (after 2–5 min of right atrial pacing at 120–140 beats/min, and when expressed as percentage of control cycle length, it normally ranges from 115–159%). survival t. 1. the period elapsing between the completion or institution of any procedure and death; 2. the lifespan of biologically or physically marked erythrocytes or other cells. thrombin t. the t. needed for a fibrin clot to form after the addition of thrombin to citrated plasma; prolonged thrombin t. is seen in patients receiving heparin therapy. tissue thromboplastin inhibition t. a test used to identify lupus anticoagulant; the thromboplastin source used in the prothrombin test is diluted to increase sensitivity to inhibitors. utilization t. the minimum duration of a stimulus of rheobasic strength that is just sufficient to produce excitation. SYN: temps utile.
Acronym for thrombolysis in myocardial infarction; a large multicenter controlled clinical trial.
timnodonic acid (tim-no-don′ok)
A 20-carbon fatty acid with five cis double bonds located on carbons 5, 8, 11, 14, and 17; an important component of fish oils; a precursor to the 3-series prostaglandins, e.g., PGE3.
timolol maleate (ti′mo-lol)
A β-adrenergic blocking agent used in the treatment of hypertension and used in eyedrops in the treatment of chronic open-angle glaucoma.
tin (Sn) (tin)
A metallic element, atomic no. 50, atomic wt. 118.710. SYN: stannum. [AS, t.] t. oxide SYN: stannic oxide.
A radioisotope of tin with a physical half-life of 115.1 days; used in the manufacture of radionuclide generators for the production of indium-113m.
Abbreviation of L. tinctura, tincture.
1. A stain; a preparation for staining. 2. The act of staining. [L. tingo, pp. tinctus, to dye]
Relating to coloring or staining. [L. tinctorius, fr. tingo, to dye]
tinctura, gen. and pl. tincturae (tingk-too′ra, -re)
SYN: tincture. [L. a dyeing, fr. tingo, pp. tinctus, to dye]
An alcoholic or hydroalcoholic solution prepared from vegetable materials or from chemical substances; most tinctures are prepared by percolation or by maceration. The proportions of drug represented in the different tinctures are not uniform, but vary according to the established standards for each. Tinctures of potent drugs essentially represent the activity of 10 g of the drug in each 100 mL of t., the potency being adjusted after assay; most other tinctures represent 20 g of drug in each 100 mL of t.. Compound tinctures are made according to long-established formulas. SYN: tinctura. alcoholic t. a t. made with undiluted alcohol. ammoniated t. a t. made with ammoniated alcohol. belladonna t. a green hydroalcoholic mobile liquid containing the alkaloids atropine and scopolamine and other substances extracted from the leaves of Atropa belladonna, the botanical source for these anticholinergic drugs. The t. allows for gradual titration of dose by counting drops of the preparation ingested. Formerly widely used in ulcer therapy or the symptomatic treatment of diarrhea, alone or in combination with antacids and insoluble clays. digitalis t. an hydroalcoholic solution containing the glycosides of the leaves of the foxglove (digitalis) plant Digitalis purpurea or D. lanata. Although digitalis preparations are used extensively, they are currently used as the pure glycosides, digoxin and digitoxin. The t. was formerly widely used but was standardized by bioassay using frogs, cats, or pigeons. ethereal t. a class of preparations consisting of 10% percolations of drugs in a menstruum of ether (1) and alcohol (2). glycerinated t. a t. made with diluted alcohol to which glycerin is added to facilitate the extraction or to preserve the preparation. green soap t. a liquid preparation containing potassium soaps and alcohol; frequently advocated in skin cleansing, particularly after exposure to plant toxins such as poison ivy. hydroalcoholic t. a t. made with diluted alcohol in various proportions with water.
1. In dentistry, the slender, pointed end of an explorer. 2. An instrument used to introduce antigen, such as tuberculin into the skin, and usually containing several individual tines. [A.S. tind, a prong]
A fungus infection (dermatophytosis) of the keratin component of hair, skin, or nails. Genera of fungi causing such infection are Microsporum, Trichophyton, and Epidermophyton. SYN: ringworm, serpigo (1) . [L. worm, moth] t. barbae a fungus infection of the beard, occurring as a follicular infection or as a granulomatous lesion; the primary lesions are papules and pustules. SYN: barber itch, folliculitis barbae, ringworm of beard, t. sycosis. t. capitis a common form of fungus infection of the scalp caused by various species of Microsporum and Trichophyton on or within hair shafts, occurring most commonly in children and characterized by irregularly placed and variously sized patches of apparent baldness because of hairs breaking off at the surface of the scalp, scaling, black dots (see black-dot ringworm), and occasionally erythema and pyoderma. SYN: ringworm of scalp. t. circinata SYN: t. corporis. t. corporis a well-defined, scaling, macular eruption of dermatophytosis that frequently forms annular lesions and may appear on any part of the body. SYN: ringworm of body, t. circinata. t. favosa SYN: favus. t. glabrosa ringworm or fungus infection of the hairless skin. t. imbricata an eruption consisting of a number of concentric rings of overlapping scales forming papulosquamous patches scattered over the body; it occurs in tropical climates and is caused by the fungus Trichophyton concentricum. SYN: Oriental ringworm, scaly ringworm, Tokelau ringworm. t. kerion an inflammatory fungus infection of the scalp and beard, marked by pustules and a boggy infiltration of the surrounding parts; most commonly caused by Microsporum audouinii. t. manus ringworm of the hand, usually referring to infections of the palmar surface. SEE ALSO: t. corporis. t. nigra a fungus infection due to Exophiala werneckii, marked by dark lesions giving a spattered appearance and occurring most commonly on the palms of the hands. SYN: pityriasis nigra. t. pedis dermatophytosis of the feet, especially of the skin between the toes, caused by one of the dermatophytes, usually a species of Trichophyton or Epidermophyton; the disease consists of small vesicles, fissures, scaling, maceration, and eroded areas between the toes and on the plantar surface of the foot; other skin areas may be involved. SYN: athlete's foot, dermatomycosis pedis, ringworm of foot. t. profunda SYN: Majocchi granulomas, under granuloma. t. sycosis SYN: t. barbae. t. tonsurans t. capitis or t. corporis caused by the fungus Trichophyton tonsurans; characterized by small plaques and fewer broken off hairs than in t. capitis caused by other species. t. unguium ringworm of the nails due to a dermatophyte. t. versicolor an eruption of tan or brown branny patches on the skin of the trunk, often appearing white, in contrast with hyperpigmented skin after exposure to the summer sun; caused by growth of the fungus Malassezia furfur in the stratum corneum with minimal inflammatory reaction. SYN: pityriasis versicolor.
Jules, French neurologist, 1879–1952. See T. sign.
1. Tin rolled into extremely thin sheets. 2. A base metal foil used as a separating material, as between the cast and denture base material during flasking and curing procedures.
The property of being tingible.
Capable of being stained. [L. tingo, to dye]
To feel a peculiar pricking sensation.
A pricking type of paresthesia. distal t. on percussion (DTP) SYN: Tinel sign.
An antiprotozoal agent.
Noises (ringing, whistling, hissing, roaring, booming, etc.) in the ears. [L. a jingling, fr. tinnio, pp. t., to jingle, clink] t. aurium sensation of sound in one or both ears usually associated with disease in the middle ear, the inner ear, or the central auditory pathways. SYN: syrigmus. t. cerebri subjective sensation of noise in head rather than ears. clicking t. an objective clicking sound in the ear in cases of chronic catarrhal otitis media; it may be audible to the bystander as well as to the patient and is supposed to be due to an opening and closing of the mouth of the eustachian tube, or to a rhythmical spasm of the velum palati. Leudet t. a dry spasmodic click, audible also through the otoscope, heard in catarrhal inflammation of the eustachian tube; caused by reflex spasm of the tensor palati muscle.
A shade of color varying according to the amount of white admixed with the pigment. [L. tingo, pp. tinctus, to dye]
An antifungal agent.
1. A point; a more or less sharp extremity. 2. A separate, but attached, piece of the same or another structure, forming the extremity of a part. t. of auricle SYN: apex of auricle. t. of ear apex of auricle. t. of elbow SYN: olecranon. t. of nose apex of nose. t. of posterior horn SYN: apex of posterior horn. root t. SYN: root apex. t. of tongue apex of tongue. t. of tooth root SYN: root apex. Woolner t. SYN: apex of auricle.
A tooth movement in which the angulation of the long axis of the tooth is altered.
tiprenolol hydrochloride (tip-ren′o-lol)
A β-receptor blocking agent.
Acronym for transjugular intrahepatic portosystemic shunt.
Arne W.K., Swedish biochemist and Nobel laureate, 1902–1971. See T. apparatus, T. electrophoresis cell.
SYN: Bacteroides praeacutus.
Jules, early 20th century French physiologist. See T. spirometer.
A collection of similar cells and the intercellular substances surrounding them. There are four basic tissues in the body: 1) epithelium; 2) connective tissues, including blood, bone, and cartilage; 3) muscle t.; and 4) nerve t.. [Fr. tissu, woven, fr. L. texo, to weave] adenoid t. SYN: lymphatic t.. adipose t. a connective t. consisting chiefly of fat cells surrounded by reticular fibers and arranged in lobular groups or along the course of one of the smaller blood vessels. SYN: fat (1) , fatty t. (1) , white fat (1) . areolar t. loose, irregularly arranged connective t. that consists of collagenous and elastic fibers, a protein polysaccharide ground substance, and connective t. cells (fibroblasts, macrophages, mast cells, and sometimes fat cells, plasma cells, leukocytes, and pigment cells). bone t. SYN: osseous t.. bronchus-associated lymphoid t. (BALT) patches of lymphoid tissues composed mainly of B and T lymphocytes and extending throughout the bronchial airways of the lung. brown adipose t. SYN: brown fat. cancellous t. latticelike or spongy osseous t.. cardiac muscle t. cardiac muscle. cartilaginous t. cartilage. cavernous t. SYN: erectile t.. chondroid t. 1. in an adult, t. resembling cartilage; SYN: fibrohyaline t., pseudocartilage. 2. in an embryo, an early stage in cartilage formation. chromaffin t. a cellular t., vascular and well supplied with nerves, made up chiefly of chromaffin cells; it is found in the medulla of the suprarenal glands and, in smaller collections, in the paraganglia. connective t. the supporting or framework t. of the animal body, formed of fibrous and ground substance with more or less numerous cells of various kinds; it is derived from the mesenchyme, and this in turn from the mesoderm; the varieties of connective t. are: areolar or loose; adipose; dense, regular or irregular, white fibrous; elastic; mucous; and lymphoid t.; cartilage; and bone; the blood and lymph may be regarded as connective tissues the ground substance of which is a liquid. SYN: interstitial t., tela conjunctiva. dartoic t. t. resembling tunica dartos. elastic t. a form of connective t. in which the elastic fibers predominate; it constitutes the ligamenta flava of the vertebrae and the ligamentum nuchae, especially of quadrupeds; it occurs also in the walls of the arteries and of the bronchial tree, and connects the cartilages of the larynx. SYN: elastica (2) , tela elastica. epithelial t. epithelium. erectile t. a t. with numerous vascular spaces that may become engorged with blood. SYN: cavernous t.. fatty t. 1. SYN: adipose t.. 2. in some animals, brown fat. fibrohyaline t. SYN: chondroid t. (1) . fibrous t. a t. composed of bundles of collagenous white fibers between which are rows of connective t. cells; the tendons, ligaments, aponeuroses, and some of the membranes, such as the dura mater. Gamgee t. a thick layer of absorbent cotton between two layers of absorbent gauze, used in surgical dressings. gelatinous t. SYN: mucous connective t.. gingival tissues gingiva. granulation t. vascular connective t. forming granular projections on the surface of a healing wound, ulcer, or inflamed t. surface. SEE ALSO: granulation. gut-associated lymphoid t. (GALT) lymphoid t. of the gastrointestinal mucosa that contains both B and T cells. This t. is responsible for localized immunity to pathogens such as bacteria, viruses, and parasites. Haller vascular t. SYN: vascular lamina of choroid. hard t. 1. t. that has become mineralized; 2. t. having a firm intercellular substance, e.g., cartilage and bone. hemopoietic t. t. in which there is a development of blood cells or other formed elements. indifferent t. undifferentiated, nonspecialized, embryonic t.. interstitial t. SYN: connective t.. investing tissues the tissues covering or enclosing a structure. islet t. SYN: islets of Langerhans, under islet. lymphatic t., lymphoid t. a three-dimensional network of reticular fibers and cells the meshes of which are occupied in varying degrees of density with lymphocytes; there is nodular, diffuse, and loose lymphatic t.. SYN: adenoid t.. mesenchymal t. embryonic connective t.. See mesenchyme. mesonephric t. intermediate mesoderm situated in the thoracic and lumbar regions of the embryo or fetus; it develops into the mesonephros and associated structures. metanephrogenic t. t. derived from the intermediate mesoderm caudal to mesonephric levels and concerned with the formation of the nephrons of the metanephros. mucosa-associated lymphoid t. (MALT) a class of lymphoid t. comprising nodular aggregates found in association with the wet mucosal surfaces of the body such as those of the respiratory, digestive, and urinary systems. mucous connective t. a type of connective t. little differentiated beyond the mesenchymal stage; its ground substance of glycoproteins is abundant and contains fine collagenous fibers and fibroblasts; in its most characteristic form, it appears in the umbilical cord as Wharton jelly. SYN: gelatinous t.. multilocular adipose t. SYN: brown fat. muscular t. a t. characterized by the ability to contract upon stimulation; its three varieties are skeletal, cardiac, and smooth. See muscle. SYN: flesh (2) . myeloid t. bone marrow consisting of the developmental and adult stages of erythrocytes, granulocytes, and megakaryocytes in a stroma of reticular cells and fibers, with sinusoidal vascular channels. nasion soft t. the outer point of intersection between the nasion-sella line and the soft t. profile. nephrogenic t. the t. from which the pronephros, mesonephros, and metanephros develop. nervous t. a highly differentiated t. composed of nerve cells, nerve fibers, dendrites, and a supporting t. (neuroglia). nodal t. See atrioventricular node, sinuatrial node. osseous t. a connective t., the matrix of which consists of collagen fibers and ground substance and in which are deposited calcium salts (phosphate, carbonate, and some fluoride) in the form of an apatite. SYN: bone t.. osteogenic t. a connective t. with the property of forming osseous t.. osteoid t. osseous t. prior to calcification. periapical t. the structures adjacent to a root apex, particularly the periodontal ligament and bone. reticular t., retiform t. a t. in which the argyrophilic collagenous fibers form a network and that usually has a network of reticular cells associated with the fibers. rubber t. a thin sheet of rubber used as a cover in surgical dressings. skeletal muscle t. skeletal muscle. smooth muscle t. smooth muscle. subcutaneous t. [TA] an irregular layer of loose connective t. immediately deep to the skin and superficial to the deep fascia, usually consisting primarily of a fatty layer [TA] (panniculus adiposus [TA]) which may also include a muscle layer [TA] (stratum musculosum [TA]) and/or a fibrous layer [TA] (stratum fibrosum [TA]}, or it may occur as a membranous layer [TA] (stratum membranosum [TA]) only, being nearly devoid of fat (as in the auricles, eyelids, scrotum, and penis); it is penetrated by, and gains support from, skin ligaments [TA] (retinacula cutis [TA]) extending between the dermis and the deep fascia; cutaneous nerves and superficial vessels course within the subcutaneous t., with only their terminal branches passing to the skin; of the body's coverings, this layer varies most between sexes and in different nutritional states. Terminologia Anat omica [TA] has recommended that the terms “superficial fascia” and “deep fascia” not be used generically in an unqualified way because of variation in their meanings internationally. The recommended terms are “subcutaneous t. [TA] (tela subcutanea)” for the former superficial fascia, and “muscular fascia” or “visceral fasci viscera[is]) in place of deep fascia. SYN: tela subcutanea [TA] , hypodermis&star, fascia superficialis, hypoderm, stratum subcutaneum, subcutis, superficial fascia. subcutaneous t. of penis [TA] a superficial layer continuous with fascia perinei superficialis. SYN: fascia penis superficialis, superficial fascia of penis. subcutaneous t. of perineum [TA] the membranous layer of the subcutaneous t. in the urogenital region attaching posteriorly to the border of the urogenital diaphragm, at the sides to the ischiopubic rami, and continuing anteriorly onto the abdominal wall. SYN: Colles fascia, Cruveilhier fascia, fascia perinei superficialis, membranous layer of superficial fascia of perineum (1) , membranous layer of superficial fascia (1) , superficial fascia of perineum. trabecular t. of sclera [TA] the network of fibers (pectinate ligaments) at the iridocorneal angle between the anterior chamber of the eye and the venous sinus of the sclera; it contains spaces between the fibers that are involved in drainage of the aqueous humor, and is composed of two portions: the corneoscleral part (the part attached to the sclera) and the uveal part (the part attached to the iris). SYN: reticulum trabeculare sclerae [TA] , Gerlach valvula, Hueck ligament, ligamentum anulare bulbi, pectinate ligaments of iridocorneal angle, pillar of iris, trabecular meshwork, trabecular network, trabecular reticulum, trabecular zone.
SYN: border molding.
Relating or pertaining to a tissue.
titanium (Ti) (ti-ta′ne-um)
A metallic element, atomic no. 22, atomic wt. 47.88. [Titans, in G. myth., sons of Earth] t. dioxide TiO2;contains not less than 99.0% and not more than 100.5% of TiO2, calculated on the dry basis; used in creams and powders as a protectant against external irritations and solar rays.
The standard of strength of a volumetric test solution; the assay value of an unknown measure by volumetric means. [Fr. titre, standard]
Abbreviation for 3,5,3′-triiodothyronine.
The act or sensation of tickling. [L. titillatio, fr. titillo, pp. -atus, to tickle]
A very large fibrous protein that connects thick myosin filaments to Z discs in the sarcomere.
In chemistry, the solution that is added (titrated with) in a titration.
To analyze volumetrically by a solution (the titrant) of known strength to an end point.
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