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Medical Dictionary - Dictionary of Medicine and Human Biology

Medical Dictionary


iniad (in′e-ad)
In a direction toward the inion. [L. ad, to]

inial (in′e-al)
SYN: iniac.

iniencephaly (in′e-en-sef′a-le)
Malformation consisting of a cranial defect at the occiput, with the brain exposed; often in combination with a cervical rachischisis and retroflexion. [G. inion, back of the head, + enkephalos, brain]

inion (in′e-on) [TA]
A point located on the external occipital protuberance at the intersection of the midline with a line drawn tangent to the uppermost convexity of the right and left superior nuchal lines. [G. nape of the neck]

iniopagus (in′e-op′a-gus)
SYN: craniopagus occipitalis. [inion + G. pagos, fixed]

iniops (in′e-ops)
SYN: janiceps asymmetrus. [inion + G. ops, eye, face]

initiation (i-ni-she-a′shun)
1. The first stage of tumor induction by a carcinogen; subtle alteration of cells by exposure to a carcinogenic agent so that they are likely to form a tumor upon subsequent exposure to a promoting agent (promotion). 2. Starting point of replication or translation in macromolecule biosynthesis. 3. Start of chemical or enzymatic reaction. 4. The first step in a chain reaction.

initis (in-i′tis)
1. Inflammation of fibrous tissue. 2. SYN: myositis. [G. is (in-), fiber, + -itis, inflammation]

inject (in-jekt′)
To introduce into the body; denoting a fluid forced beneath the skin or into a blood vessel. SEE ALSO: injection. [L. injicio, to throw in]

injectable (in-jek′ta-bl)
1. Capable of being injected into anything. 2. Capable of receiving an injection.

injected (in-jek′ted)
1. Denoting a fluid introduced into the body. 2. Denoting visible blood vessels distended with blood.

injection (in-jek′shun)
1. Introduction of a medicinal substance or nutrient material into the subcutaneous tissue (subcutaneous or hypodermic i.), the muscular tissue (intramuscular i.), a vein (intravenous i.), an artery (intraarterial i.), the rectum (rectal i. or enema), the vagina (vaginal i. or douche), the urethra, or other canals or cavities of the body. 2. An injectable pharmaceutical preparation. 3. Congestion or hyperemia. [L. injectio, a throwing in, fr. in-jicio, to throw in] adrenal cortex i. obsolete treatment involving the parenteral administration of extract of the adrenal cortex; formerly used in treatment of Addison disease. collagen i. correction of superficial soft tissue deformities, acne scars, or age-related skin changes by i. (implantation) of collagen; bovine collagen preparations are commonly used. Prior intradermal testing is necessary to exclude hypersensitivity. SYN: collagen implantation. depot i. an i. of a substance in a vehicle that tends to keep it at the site of i. so that absorption occurs over a prolonged period. hypodermic i. the administration of a remedy in liquid form by i. into the subcutaneous tissues. SYN: hypodermic (2) . insulin i. a preparation that usually contains 100 USP insulin units per ml; it is administered subcutaneously, occasionally intravenously, and has a rapid onset of action, has a brief duration (5 to 7 hours), and is compatible for mixing with long-acting insulin preparations; used in the treatment of diabetic acidosis and insulin coma. SYN: regular insulin i.. intracytoplasmic sperm i. a procedure in which a single sperm cell is injected into the oocyte during in vitro fertilization. intrathecal i. introduction of material for diffusion throughout the subarachnoid space by means of lumbar puncture. intraventricular i. the introduction of materials for diffusion throughout the ventricular and subarachnoid space by means of ventricular puncture. jet i. hypodermic i. of drugs by a jet injector. lactated Ringer i. a sterile solution of calcium chloride, potassium chloride, sodium chloride, and sodium lactate in water for i.; used intravenously as a systemic alkalizer and a fluid and electrolyte replenisher. regular insulin i. SYN: insulin i.. Ringer i. a sterile solution of sodium chloride, potassium chloride, and calcium chloride, containing in each 100 ml between 820 and 900 mg of sodium chloride, between 25 and 35 mg of potassium chloride, and between 30 and 37 mg of calcium chloride; used intravenously as a fluid and electrolyte replenisher. selective i. i. of contrast medium following selective catheterization of a branch artery or vein for angiography. sensitizing i. an i. that sensitizes a person so that subsequent exposure to the antigen (allergen) evokes an allergic response. test i. intravenous i. of a few milliliters of radiographic contrast medium to screen for allergic or idiosyncratic responses. Z-tract i. a technique in which the skin and subcutaneous tissue are displaced laterally before inserting the needle intramuscularly; used to prevent leakage along the track of the needle and consequent tissue irritation.

injector (in-jek′ter)
A device for making injections. jet i. an i. that uses high pressure to force a liquid through a small orifice at a velocity sufficient to penetrate skin or mucous membrane without the use of a needle. power i. an i. for rapid contrast medium injection in angiography or computed tomography.

injure (in′jer)
To wound, hurt, or harm.

injury (in′jer-e)
The damage or wound of trauma. [L. injuria, fr. in- neg. + jus (jur-), right] blast i. tearing of lung tissue or rupture of any tissue or organ without external i., as by the force of an explosion. brachial plexus i. damage to the brachial plexus related to delivery; associated with excessive lateral stretching of the head, typically in cases of shoulder dystocia or breech deliveries. SEE ALSO: brachial birth palsy. closed head i. a head i. in which continuity of the scalp and mucous membranes is maintained. contrecoup i. of brain an i. occurring beneath the skull opposite to the area of impact. coup i. of brain an i. occurring directly beneath the skull at the area of impact. current of i. See current of i.. degloving i. avulsion of the skin of a portion of the body (most commonly on the extremities) in which the part is skeletonized by removal of most or all of the skin and subcutaneous tissue. egg-white i. SYN: egg-white syndrome. flexion-extension i. forceful application of a forward and backward movement of the unsupported head that may produce an i. to the cervical spine or the brain. hyperextension-hyperflexion i. violence to the body causing the unsupported head to move rapidly backward and forward resulting in hyperextension and hyperflexion of the neck; does not imply any specific resultant trauma or pathology. i. of intervertebral disk traumatic cervical discopathy. open head i. a head i. in which there is a loss of continuity of scalp or mucous membranes; the term is sometimes used to indicate a communication between the exterior and the intracranial cavity. SEE ALSO: penetrating wound. pneumatic tire i. separation of the skin and subcutaneous tissue from the underlying fascia, classically occurring when an extremity is crushed and rolled over by the tire of a vehicle; however, it may be incurred through other mechanisms that produce shear forces; similar to a degloving i., except that the skin and subcutaneous tissue layers remain in continuity. reperfusion i. myocardial impairment, usually with arrhythmia, following the opening of arterial blockage and considered to be due to oxygen-derived free radicals. steering wheel i. trauma to the anterior chest wall caused by impact with the steering wheel during an automobile accident; can include fractured sternum and ribs, cardiac contusion, tear of the aorta or other great vessels, as well as lung injuries. whiplash i. popular term for flexion-extension i..

inlay (in′la)
1. In dentistry, a prefabricated restoration sealed in the cavity with cement. 2. A graft of bone into a bone cavity. 3. A graft of skin into a wound cavity for epithelialization. 4. In orthopedics, an orthomechanical device inserted into a shoe; commonly called an “arch support.” epithelial i. SYN: i. graft. gold i. a gold restoration fabricated by casting in a mold made from a wax pattern; the restoration is sealed in the prepared cavity with dental cement. porcelain i. a fused porcelain restoration luted in a cavity prepared in a tooth.

inlet [TA]
A passage leading into a cavity. SYN: aditus [TA] . laryngeal i. [TA] the aperture between the pharynx and larynx, bounded by the superior edges of the epiglottis (anteriorly), the aryepiglottic folds (laterally), and the mucosa between the arytenoids (posteriorly). SYN: aditus laryngis [TA] , laryngeal aditus [TA] , i. of larynx, laryngeal aperture. i. of larynx SYN: laryngeal i.. pelvic i. [TA] the upper opening of the true pelvis, bounded anteriorly by the pubic symphysis and the pubic crest on either side, laterally by the iliopectineal lines, and posteriorly by the promontory of the sacrum. SYN: apertura pelvis superior [TA] , aditus pelvis, first parallel pelvic plane, pelvic brim, pelvic plane of i., plane of i., superior pelvic aperture. thoracic i. SYN: superior thoracic aperture.

innate (i′nat, i-nat′)
SYN: inborn. [L. in-nascor, pp. -natus, to be born in, pp. as adj. inborn, i.]

innervation (in′er-va′shun)
The supply of nerve fibers functionally connected with a part. [L. in, in, + nervus, nerve] reciprocal i. contraction in a muscle is accompanied by a loss of tone or by relaxation in the antagonistic muscle. SYN: reciprocal inhibition (1) .

innidiation (i-nid-e-a′shun)
The growth and multiplication of abnormal cells in another location to which they have been transported by means of lymph or blood stream, or both. SEE ALSO: metastasis. SYN: colonization (1) , indenization. [L. in, in, + nidus, nest]

innocent (in′o-sent)
1. Not apparently harmful. 2. Free from legal or moral wrong. [L. innocens (-ent-), fr. in, neg., + noceo, to injure]

innocuous (i-nok′u-us)
Harmless. SYN: innoxious. [L. innocuus]

innominatal (i-nom′i-na-tal)
Relating to the hip bone.

innominate (i-nom′i-nat)
Without name; a term formerly applied to the large vessels in the thorax (now called the brachiocephalic trunk and vein) and the hip bone. SYN: anonyma. [L. innominatus, fr. in- neg. + nomen (nomin-), name]

innoxious (i-nok′shus)
SYN: innocuous. [L. in-noxius, fr. in, neg. + noceo, to injure]

Acronym for internuclear ophthalmoplegia.

Symbol for inosine.

ino-, in-
Fiber, fibrous. SEE ALSO: fibro-. [G. is (in-), fiber]

inoculability (i-nok′u-la-bil′i-te)
The quality of being inoculable.

inoculable (i-nok′u-la-bl)
1. Transmissible by inoculation. 2. Susceptible to a disease transmissible by inoculation.

inoculate (i-nok′u-lat)
1. To introduce the agent of a disease or other antigenic material into the subcutaneous tissue or a blood vessel, or through an abraded or absorbing surface for preventive, curative, or experimental purposes. 2. To implant microorganisms or infectious material into or upon culture media. 3. To communicate a disease by transferring its virus. [L. inoculo, pp. -atus, to ingraft]

inoculation (i-nok-u-la′shun)
Introduction into the body of the causative organism of a disease. Also sometimes used, incorrectly, to mean immunization with any type of vaccine. stress i. in clinical psychology, an approach intended to provide patients with cognitive and attitudinal skills that they can use to cope with stress.

inoculum (i-nok′u-lum)
The microorganism or other material introduced by inoculation.

Inocybe (i-no′si-be)
A genus of mushrooms containing several species that have a high yield of muscarine.

inopectic (in-o-pek′tik)
Relating to inopexia.

inoperable (in-op′er-a-bl)
Denoting that which cannot be operated upon, or a condition that cannot likely be cured by surgery.

inopexia (in-o-pek′se-a)
A tendency toward spontaneous coagulation of the blood. [ino + G. pexis, fixation, + -ia]

inorganic (in-or-gan′ik)
1. Not organic; not formed by living organisms. 2. See i. compound. 3. Not containing carbon.

inosamine (in-os′a-men)
An inositol in which an &cbond;OH group is replaced by an –NH2 group.

inoscopy (in-os′ko-pe)
The microscopic examination of biologic materials ( e.g., tissue, sputum, clotted blood) after dissecting or chemically digesting the fibrillary elements and strands of fibrin. [ino- + G. skopeo, to look at]

inose (in′os)
SYN: inositol.

inosemia (in-o-se′me-a)
1. The presence of inositol in the circulating blood. 2. SYN: fibremia. [inose + G. haima, blood]

inosinate (in-o′si-nat)
A salt or ester of inosinic acid.

inosine (I, Ino) (in′o-sen)
9-β-d-Ribosylhypoxanthine;a nucleoside formed by the deamination of adenosine. SYN: hypoxanthinosine.

inosine 5′-diphosphate (IDP)
Inosine esterified at its 5′ position with diphosphoric acid.

inosine 5′-monophosphate (IMP)
SYN: inosinic acid. IMP dehydrogenase an enzyme that catalyzes the reaction of IMP, water, and NAD+ to form NADH and xanthosine 5′-monophosphate (XMP), the immediate precursor of GMP.

inosine pranobex (in′o-sen pran′o-beks)
A 1:3 molar complex of 1-dimethylaminopropan-2-ol-4-acetamidobenzoate and inosine, used as an antiviral agent.

inosine 5′-triphosphate (ITP) (in′o-sen)
Inosine with triphosphoric acid esterified at its 5′ position; participates in a number of enzyme-catalyzed reactions.

inosinic acid (in-o-sin′ik)
A mononucleotide found in muscle and other tissues; a key intermediate in purine biosynthesis; also produced in relatively high levels in muscle. SYN: inosine 5′-monophosphate.

inosinicase (in-o-sin′-a-kas)
An enzyme that functions in purine biosynthesis and catalyzes the ring closure reaction that produces inosinic acid from 5′-phosphoribosyl 5-formamidoimidazole-4-carboxamide.

inosinyl (in-o′si-nil)
The radical of inosinic acid.

inosite (in′o-sit)
SYN: inositol.

inositide (in-o′si-tid)
Term used for phosphatidylinositol or any inositol-containing phospholipid.

inositol (in-o′si-tol, -tol)
1,2,3,4,5,6-Hexahydroxycyclohexane;a member of the vitamin B complex necessary for growth of yeast and of mice; absence from the diet causes alopecia and dermatitis in mice and “spectacle eyes” in rats. It occurs in a number of stereoisomeric forms: cis-, epi-, allo-, neo-, myo-, muco-, chiro-, and scyllo-inositols; the most abundant naturally occurring i. is myo-i. (usually meant when “i.” occurs without a prefix). SYN: antialopecia factor, inose, inosite, lipositol, mouse antialopecia factor. i. niacinate a peripheral vasodilator. i. 1,3,4,5-tetraphosphate a phosphorylated derivative of i. formed from i. 1,4,5-trisphosphate that causes Ca2+ entry into the cytosol from the extracellular medium; inactivated by hydrolysis to form i. 1,3,4-trisphosphate. i. 1,4,5-trisphosphate (IP3) a second messenger formed from phosphatidylinositol 4,5-bisphosphate; triggers the release of calcium ions from special vesicles of the endoplasmic reticulum; has a role in the activation of neutrophils.

inosituria (in′o-si-too′re-a)
The excretion of inositol in the urine. SYN: inosuria (1) . [inositol + G. ouron, urine]

inosuria (in-o-soo′re-a)
1. SYN: inosituria. 2. The occurrence of fibrin in the urine.

inotropic (in-o-trop′ik)
Influencing the contractility of muscular tissue. [ino- + G. tropos, a turning] negatively i. weakening muscular action. positively i. strengthening muscular action.

Inoviridae (i-no-vir′i-de)
A family of filamentous viruses that infect Gram-negative bacteria with a genome of single-stranded DNA (MW 1.9–2.7 × 106). Coliphage fd, the type species of the fd phage group genus, adsorbs to the tips of pili of male enterobacteria and, after multiplication, particles are released without causing lysis of the host bacterium. [ino- + virus]

in phase
Moving in the same direction at the same time; a possible characteristic of two simultaneous oscillations of similar frequency.

inquest (in′kwest)
A legal inquiry into the cause of sudden, violent, or mysterious death. [L. in, in, + quaero, pp. quaesitus, to seek]

inquiline (in′kwi-lin, -lin)
An animal that lives habitually in the abode of some other species (an oyster crab within the shell of an oyster) causing little or no inconvenience to the host. SEE ALSO: commensal. [L. inquilinus, an inhabitant of a place that is not his own, fr. in, in, + colo, to inhabit]

Abbreviation for international normalized ratio.

insalubrious (in-sa-loo′bre-us)
Unwholesome; unhealthful; usually in reference to climate. [L. in-salubris, unwholesome]

insane (in-san′)
1. Of unsound mind; severely mentally impaired; deranged; crazy. 2. Relating to insanity. [L. in- neg. + sanus, sound, sane]

insanitary (in-san′i-tar-e)
Injurious to health, usually in reference to an unclean or contaminated environment. SYN: unsanitary. [L. in- neg. + sanus, sound]

insanity (in-san′i-te)
1. An outmoded term referring to severe mental illness or psychosis. 2. In law, that degree of mental illness which negates the individual's legal responsibility or capacity. [L. in- neg. + sanus, sound] criminal i. in forensic psychiatry, a term that describes the degree of mental competence and that is defined by such currently applicable legal precedents as the American Law Institute rule, Durham rule, M'Naghten rule, and the New Hampshire rule. i. defense in forensic psychiatry, the use in the courtroom of i. as a mitigating factor in the defense of an individual on trial for a serious criminal offense. See criminal i..


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