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Medical Dictionary - Dictionary of Medicine and Human Biology

Medical Dictionary


intravascular (in′tra-vas′ku-lar)
Within the blood vessels or lymphatics.

intravenous (I.V., i.v.) (in′tra-ve′nus)
Within a vein or veins. SYN: endovenous.

intraventricular (I-V) (in′tra-ven-trik′u-lar)
Within a ventricle of the brain or heart.

intravesical (in′tra-ves′i-kal)
Within a bladder, especially the urinary bladder.

intra vitam (in′tra vi′tam)
During life. [L. vita, life]

intravitelline (in′tra-vi-tel′in, -en)
Within the vitellus yolk.

intravitreous (in′tra-vit′re-us)
Within the vitreous body.

intrinsic (in-trin′sik)
1. Belonging entirely to a part. 2. In anatomy, denoting those muscles whose origin and insertion are both within the structure under consideration, distinguished from the extrinsic muscles that have their origin outside of the structure under consideration; applied especially to the limbs but also to the ciliary muscle as distinguished from the recti and other orbital muscles which are outside the eyeball. SYN: essential (6) . [L. intrinsecus, on the inside]

Inwardly, into; opposite of extra-. Cf.:intra-. [L. intro, into]

introducer (in-tro-doos′er)
An instrument, such as a catheter, needle, or endotracheal tube, for introduction of a flexible device. SYN: intubator. [L. intro-duco, to lead into, introduce]

introflection, introflexion (in′tro-flek′shun)
A bending inward. [intro- + L. flecto, pp. flectus, to bend]

introgastric (in-tro-gas′trik)
Leading or passed into the stomach. [intro- + G. gaster, belly, stomach]

introitus (in-tro′i-tus)
The entrance into a canal or hollow organ, as the vagina. [L. entrance, fr. intro-eo, to go into] i. canalis SYN: i. of facial canal. i. of facial canal entrance to facial canal, through which the facial nerve passes, at end of internal acoustic meatus. SYN: i. canalis. vaginal i. SYN: vestibule of vagina.

introject (in′tro-jekt)
The dynamically endowed, enduring internal representation of an object.

introjection (in-tro-jek′shun)
A psychological defense mechanism involving appropriation of an external happening and its assimilation by the personality, making it a part of the self. [intro- + L. jacto, to throw]

intromission (in-tro-mish′un)
The insertion or introduction of one part into another. [intro- + L. mitto, to send]

intromittent (in-tro-mit′ent)
Conveying or sending into a body or cavity.

intron (in′tron)
A portion of DNA that lies between two exons, is transcribed into RNA, but does not appear in that mRNA after maturation because the i. is removed and the exons spliced together, and so is not expressed (as protein) in protein synthesis. By customary usage, the term is extended to the corresponding regions in the primary transcript of mRNA prior to maturation. SYN: intervening sequence. [inter- + -on]

introspection (in-tro-spek′shun)
Looking inward; self-scrutinizing; contemplating one's own mental processes. [intro- + L. specto, to look at, inspect]

introspective (in-tro-spek′tiv)
Relating to introspection.

introsusception (in′tro-sus-sep′shun)
SYN: intussusception.

introversion (in-tro-ver′zhun)
1. The turning of a structure into itself. SEE ALSO: intussusception, invagination. 2. A trait of preoccupation with oneself, as practiced by an introvert. Cf.:extraversion. [intro- + L. verto, pp. versus, to turn]

1. (in′tro-vert)One who tends to be unusually shy, introspective, self-centered, and avoids becoming concerned with or involved in the affairs of others. Cf.:extrovert. 2. (in-tro-vert′)To turn a structure into itself, to invert.

intubate (in′too-bat)
To insert a tube.

intubation (in-too-ba′shun)
Insertion of a tubular device into a canal, hollow organ, or cavity; specifically, passage of an oro- or nasotracheal tube for anesthesia or for control of pulmonary ventilation. [L. in, in, + tuba, tube] altercursive i. rarely used term for diversion of secretion intermittently to the exterior from its normal destination, e.g., of the bile from the intestine. aqueductal i. insertion of a tube in the sylvian aqueduct to relieve atresia or narrowing of the aqueduct. blind nasotracheal i. passage of tube through the nose into the trachea without using a laryngoscope. endotracheal i. passage of a tube through the nose or mouth into the trachea for maintenance of the airway during anesthesia or for ventilatory support or for maintenance of an imperiled airway. SYN: intratracheal i.. intratracheal i. SYN: endotracheal i.. nasotracheal i. tracheal i. through the nose. orotracheal i. tracheal i. through the mouth. tracheal i. passage of a tube through the nose, mouth, or a tracheotomy into the trachea for maintenance of patency of the airway.

intubator (in′too-ba-tor)
SYN: introducer.

intumesce (in-too-mes′)
To swell up; to enlarge. [L. in-tumesco, to swell up, fr. tumeo, to swell]

intumescence (in-too-mes′ens)
1. SYN: enlargement. 2. The process of enlarging or swelling; used to describe the spinal enlargements. tympanic i. SYN: tympanic enlargement.

intumescent (in-too-mes′ent)
Enlarging; becoming enlarged or swollen.

intumescentia (in-too-mes-sen′she-a) [TA]
SYN: enlargement. [Mod. L.] i. cervicalis [TA] SYN: cervical enlargement. i. ganglioformis SYN: geniculate ganglion. i. lumbosacralis [TA] SYN: lumbosacral enlargement. i. tympanica [TA] SYN: tympanic enlargement.

intussusception (in′tus-su-sep′shun)
1. The taking up or receiving of one part within another, especially the enfolding of one segment of the intestine within another. SEE ALSO: introversion, invagination. 2. Often, specifically, the process of incorporation of new material in the growth of the cell wall. SYN: introsusception. [L. intus, within, + sus-cipio, to take up, fr. sub + capio, to take] colic i. the ensheathing of one portion of the colon into another. double i. a second i. that involves the bowel above the first; the first i. is followed by contraction of the bowel wall around it, and the solid mass so formed is enveloped by the proximal portion of the bowel and is thus the cause of the second i.. ileal i. i. in which one portion of the ileum is ensheathed in another portion of the same division of the bowel. ileocecal i. i. in which the lower segment of the ileum passes through the valve of the colon into the cecum. ileocolic i. i. in which the lower portion of the ileum with the valve of the cecum passes into the ascending colon. jejunogastric i. a rare complication following gastrojejunostomy in which the afferent or the efferent loop of bowel invaginates into the stomach. retrograde i. the invagination of a lower segment of the bowel into one just above.

intussusceptive (in′tus-su-sep′tiv)
Relating to or characterized by intussusception.

intussusceptum (in′tus-su-sep′tum)
The inner segment in an intussusception; that part of the bowel which is received within the other part.

intussuscipiens (in′tus-su-sip′e-enz)
The portion of the bowel, in intussusception, which receives the other portion. [L. intus, within, + suscipiens, pr. p. of suscipio, to take up]

inulase (in′u-las)
SYN: inulinase.

inulin (In) (in′u-lin)
A fructose polysaccharide from the rhizome of Inula helenium or elecampane (family Compositae) and other plants; used by intravenous injection, where it is filtered by the renal glomeruli but not re-absorbed and thus can be used to determine the rate of glomerular filtration; also used in bread for diabetics. Cf.:i. clearance. SYN: alant starch, alantin, dahlin.

inulinase (in′u-lin-as)
An enzyme acting upon 2,1-β-d-fructoside links in inulin, releasing d-fructose. SYN: inulase.

inulol (in′u-lol)
SYN: alantol.

inunction (in-ungk′shun)
Administration of a drug in ointment form by rubbing to cause absorption of the active ingredient. [L. inunctio, an anointing, fr. inunguo, pp. -unctus, to smear on]

invaccination (in-vak-si-na′shun)
Obsolete term for accidental inoculation of some disease, e.g., syphilis, during vaccination.

in vacuo (in vak′u-o)
In a vacuum, e.g., under reduced pressure. [L.]

invaginate (in-vaj′i-nat)
To ensheathe, infold, or insert a structure within itself or another. [L. in, in, + vagina, a sheath]

invagination (in-vaj′i-na′shun)
1. The ensheathing, enfolding, or insertion of a structure within itself or another. 2. The state of being invaginated. SEE ALSO: introversion, intussusception. basilar i. SYN: platybasia.

invaginator (in-vag′i-na-ter, -tor)
An instrument for pushing inward any tissue.

invalid (in′va-lid)
1. Weak; sick. 2. A person partially or completely disabled. [L. in- neg. + validus, strong]

invalidism (in′va-lid-izm)
The condition of being an invalid.

invasin (in-va′sin)
SYN: hyaluronidase (1) .

invasion (in-va′zhun)
1. The beginning or incursion of a disease. 2. Local spread of a malignant neoplasm by infiltration or destruction of adjacent tissue; for epithelial neoplasms, i. signifies infiltration beneath the epithelial basement membrane. 3. Entrance of foreign cells into a tissue, such as polymorphonuclear leukocytes in inflammation. [L. invasio, fr. in-vado, pp. -vasus, to go into, attack]

invasive (in-va′siv)
1. Denoting or characterized by invasion. 2. Denoting a procedure requiring insertion of an instrument or device into the body through the skin or a body orifice for diagnosis or treatment.

inventory (in′ven-tor-e)
A detailed, often descriptive, list of items. Millon clinical multiaxial i. (MCMI) SYN: Millon Clinical Multiaxial I. test. Minnesota Multiphasic Personality I. SYN: Minnesota Multiphasic Personality I. test. personality i. a psychological test for evaluation of habitual modes of behavior, thinking, and feeling based on the comparable characteristics of individuals in one's peer group.

invermination (in-ver-mi-na′shun)
SYN: helminthiasis. [L. in, in, + vermis (vermin-), worm]

inversion (in-ver′zhun)
1. A turning inward, upside down, or in any direction contrary to the existing one. 2. Conversion of a disaccharide or polysaccharide by hydrolysis into a monosaccharide; specifically, the hydrolysis of sucrose to d-glucose and d-fructose; so called because of the change in optical rotation. 3. Alteration of a DNA molecule made by removing a fragment, reversing its orientation, and putting it back into place. 4. Heat-induced transition of silica, in which the quartz tridymite or cristobalite changes its physical properties as to thermal expansion. 5. Conversion of a chiral center into its mirror image. [L. inverto, pp. -versus, to turn upside down, to turn about] i. of chromosomes a chromosome aberration resulting from a double break in a segment of the chromosome, with end for end rotation of the fragment between the fracture lines, and refusion of the fragments; this results in reversal of the order of genes in that segment. paracentric i. i. in a chromosome of a single segment in which the centromere is not included. pericentric i. i. in a chromosome of a single segment that includes the centromere. i. of the uterus a turning of the uterus inside out, usually following childbirth. visceral i. SYN: situs inversus viscerum.

invert (in′vert)
1. In chemistry, subjected to inversion, e.g., i. sugar. 2. To reverse in direction, sequence, or effect. 3. Rarely used term for a homosexual. See inversion.

invertase (in′ver-tas)
SYN: β-fructofuranosidase.

Invertebrata (in-ver-te-bra′ta)
A general category of the kingdom Animalia (multicellular animals) including those phyla whose members lack a notochord; i.e., all animals except vertebrates in the phylum Chordata.

invertebrate (in-ver′te-brat)
1. Not possessed of a spinal or vertebral column. 2. Any animal that has no spinal column.

inverted repeat
A sequence of nucleotides that is repeated nearly without change except in the opposite direction, usually at some point distant from the original sequence; often associated with gene insertion.

invertin (in′ver-tin)
SYN: β-fructofuranosidase.

invertor (in-ver′ter, -tor)
A muscle that inverts or causes inversion or turns a part, such as the foot, inward. [see inversion]

1. In dentistry, covering or enveloping wholly or in part an object such as a denture, tooth, wax form, crown, etc., with a refractory investment material before curing, soldering, or casting. 2. In psychoanalysis, allocating to or charging an object with psychic energy or cathexis. vacuum i. the i. of a pattern utilizing a vacuum to remove trapped air from the investment material.

1. In dentistry, any material used in investing. 2. In psychoanalysis, the psychic charge or cathexis invested in an object. refractory i. an i. material which can withstand the high temperatures used in soldering or casting.

inveterate (in-vet′er-at)
Long seated; firmly established; said of a disease or of confirmed habits. [L. in-vetero, pp. -atus, to render old, fr. vetus, old]

inviscation (in-vis-ka′shun)
1. Smearing with mucilaginous matter. 2. The mixing of the food, during mastication, with saliva. [L. in, in, on, + viscum, birdlime]

in vitro (in ve′tro)
In an artificial environment, referring to a process or reaction occurring therein, as in a test tube or culture media. Cf.:in vivo. [L. in glass]

in vivo (in ve′vo)
In the living body, referring to a process or reaction occurring therein. Cf.:in vitro. [L. in the living being]

involucre (in′vo-loo-ker)
SYN: involucrum.

involucrin (in-vo-loo′krin)
A non–keratin-soluble precursor of the highly cross-linked protein known as the corneocyte envelope. [fr. L. involucrum, a wrapper]

involucrum, pl .involucra (in-vo-loo′krum, -loo′kra)
1. An enveloping membrane, e.g., a sheath or sac. 2. The sheath of new bone that forms around a sequestrum. SYN: involucre. [L. a wrapper, fr. in-volvo, to roll up]


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