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Medical Dictionary


lensometer (len-zom′e-ter)
An instrument to measure the power and cylindrical axis of a spectacle lens. SYN: focimeter, vertometer. [lens + G. metron, measure]

lensopathy (lenz-op′a-the)
The process by which tear proteins are deposited on a contact lens. [lens + G. pathos, suffering]

lenticonus (len-ti-ko′nus)
Conical projection of the anterior or posterior surface of the lens of the eye, occurring as a developmental anomaly. [lens + L. conus, cone]

lenticula (len-tik′u-la)
SYN: lentiform nucleus. [L. dim. of lens]

lenticular (len-tik′u′lar)
1. Relating to or resembling a lens of any kind. 2. Of the shape of a lentil. [L. lenticula, a lentil]

lenticulo-optic (len-tik′u-lo-op′tik)
Relating to the lentiform nucleus and the optic tract; specifically refers to branches of the middle cerebral artery considered to supply these structures.

lenticulopapular (len-tik′u-lo-pap′u-lar)
Indicating an eruption with dome-shaped or lens-shaped papules.

lenticulostriate (len-tik′u-lo-stri′at)
Relating to the lenticular nucleus and the caudate nucleus; specifically refers to branches of the middle cerebral artery supplying these gray masses.

lenticulothalamic (len-tik′u-lo-tha-lam′ik)
Pertaining to the lentiform (lenticular) nucleus and the thalamus.

lenticulus, pl .lenticuli (len-tik′u-lus, -li)
Seldom-used term for an intraocular lens prosthesis placed in the anterior or posterior chamber of the eye, or attached to the iris after cataract extraction. SYN: prosthetophacos, pseudophacos. [L. dim. of lens, lentis, a little lens]

lentiform (len′ti-form)

lentigines (len-tij′i-nez)
Plural of lentigo. [L.]

lentiginosis (len-tij-i-no′sis)
Presence of lentigines in very large numbers or in a distinctive configuration. centrofacial l. [MIM*151000 & MIM*151001] uncommon autosomal dominant syndrome of small hyperpigmented macules in a horizontal band across the center of the face at one year, increasing in number up to ten years, and associated with skeletal and neural defects. generalized l. lentigines occurring singly or in groups from infancy onward.

lentiglobus (len-ti-glo′bus)
Rare congenital anomaly with a spheroid elevation on the posterior surface of the lens of the eye. [lens + L. globus, sphere]

lentigo, pl .lentigines (len-ti′go, len-tij′i-nez)
A benign, acquired brown macule resembling a freckle except that the border is usually regular and microscopic elongation of rete ridges is present, with increased melanocytes and melanin pigment in the basal cell layer. SEE ALSO: junction nevus. SYN: l. simplex. [L. fr. lens (lent-), a lentil] l. maligna a brown or black mottled, irregularly outlined, slowly enlarging lesion resembling a l. in which there are increased numbers of scattered atypical melanocytes in the epidermis, usually occurring on the face of older persons; after many years the dermis may be invaded and the lesion is then termed l. maligna melanoma. SYN: Hutchinson freckle, melanotic freckle. senile l. a variably pigmented benign l. occurring on exposed skin of older white persons. SYN: liver spot, solar l.. l. simplex SYN: l.. solar l. SYN: senile l..

Lentivirinae (len′ti-vir′i-ne)
Term formerly used to describe a subfamily of nononcogenic viruses (family Retroviridae) that includes the slow viruses of sheep (visna virus and maedi virus) and human T-cell lymphotropic viruses, including human immunodeficiency viruses 1 and 2. The viruses resemble the C-type RNA tumor viruses (Oncovirinae) in many ways, including production of reverse transcriptase. [L. lentus, sluggish, slow]

lentivirus (len′ti-vi-rus)
A genus in the family Retroviridae containing 5 serogroups that reflect the host with which they are associated. Among the primate lentiviruses are human immunodeficiency viruses 1 and 2.

lentogenic (len-to-jen′ik)
Denoting the virulence of a virus capable of inducing lethal infection in embryonic hosts after a long incubation period and an inapparent infection in immature and adult hosts; the term is used in characterizing Newcastle disease virus, particularly strains used as vaccines administered in water or as sprays, i.e., mild or avirulent strains. [L. lentus, sluggish, inactive, + G. -gen, producing]

lentula, lentulo (len′tu-la, -lo)
A motorized, flexible, spiral wire instrument used in dentistry to apply paste filling material into the root canal(s) of a tooth. [L. lentus, pliant, flexible]

leontiasis (le-on-ti′a-sis)
The ridges and furrows on the forehead and cheeks of patients with advanced lepromatous leprosy, giving a leonine appearance. SYN: leonine facies. [G. leon (leont-), lion] l. ossea SYN: megacephaly.

LEOPARD [MIM*151100]
Acronym for lentigines (multiple), electrocardiographic abnormalities, ocular hypertelorism, pulmonary stenosis, abnormalities of genitalia, retardation of growth, and deafness (sensorineural); of autosomal dominant inheritance.

leopard's bane
SYN: arnica.

Christian Gerhard, German physician, 1846–1911. See L. maneuvers, under maneuver.

Georg, German physician, *1887. See L.-Pickworth stain.

leper (lep′er)
A person who has leprosy. [G. lepra]

lepidic (le-pid′ik)
Relating to scales or a scaly covering layer. [G. lepis (lepid-), scale, rind]

Lepidoptera (lep-i-dop′ter-a)
An order of insects composed of the moths and butterflies, characterized by wings covered with delicate scales. [G. lepis, scale, + pteron, wing]

Leporipoxvirus (lep′o-ri-poks′vi-rus)
The genus of viruses (family Poxviridae) that comprises the fibroma and myxoma viruses of rabbits; unlike the orthopoxviruses, they are ether-sensitive. [L. leporis, gen. of lepus, a hare, + virus]

lepothrix (lep′o-thriks)
SYN: trichomycosis axillaris. [G. lepos, rind, husk, + thrix, hair]

leprechaunism (lep′re-kawn-izm) [MIM*246200]
A congenital form of dwarfism characterized by extreme growth retardation, endocrine disorders, and emaciation, with elfin facies and large, low-set ears; autosomal recessive inheritance; caused by mutation in the insulin receptor gene (INSR) on 19p. SYN: Donohue disease, Donohue syndrome. [Irish leprechaun, elf]

Early cutaneous lesion of leprosy. [G. lepra, leprosy, + -id (1)]

leproma (le-pro′ma)
A fairly well-circumscribed discrete focus of granulomatous inflammation, caused by Mycobacterium leprae, which consists chiefly of an accumulation of large mononuclear phagocytic cells in which the cytoplasm seems finely vacuolated ( i.e., foam cells); the foamlike character of the macrophages is related to the engulfing of numerous acid-fast organisms. [G. lepros, scaly, + -oma, tumor]

lepromatous (lep-ro′ma-tus)
Pertaining to, or characterized by, the features of a leproma.

lepromin (lep′ro-min)
An extract of tissue infected with Mycobacterium leprae used in skin tests to classify the stage of leprosy. SEE ALSO: l. reaction, test.

leprosarium (lep′ro-sar′e-um)
A hospital especially designed for the care of those suffering from leprosy, especially those who need expert care.

leprosery (lep′ro-ser-e)
A leper home or colony.

leprostatic (lep-ro-stat′ik)
1. Inhibiting to the growth of Mycobacterium leprae. 2. An agent having this action.

leprosy (lep′ro-se)
1. A chronic granulomatous infection caused by Mycobacterium leprae affecting the cooler body parts, especially the skin, peripheral nerves, and testes. L. is classified into two main types, lepromatous and tuberculoid, representing extremes of immunologic response. 2. A name used in the Bible to describe various cutaneous diseases, especially those of a chronic or contagious nature, which probably included psoriasis and leukoderma. SYN: Hansen disease. [G. lepra, from lepros, scaly] anesthetic l. a form of l. chiefly affecting the nerves, marked by hyperesthesia succeeded by anesthesia, and by paralysis, ulceration, and various trophic disturbances, terminating in gangrene and mutilation. SYN: Danielssen disease, Danielssen-Boeck disease, dry l., trophoneurotic l.. borderline l. a form of l. that is very unstable immunologically; the cutaneous nerves frequently contain bacilli, but the lepromin test is usually negative; cutaneous lesions are composed of flat bands or plaques. SYN: dimorphous l.. dimorphous l. SYN: borderline l.. dry l. SYN: anesthetic l.. histoid l. a form of lepromatous l. with lesions microscopically resembling dermatofibroma or other spindle-celled tumors. indeterminate l. a transitory form of l. in which the immunologic status is not yet formed, and the histologic and clinical features are not yet characteristic of any of the major types of l.. lepromatous l. a form of l. in which nodular cutaneous lesions are infiltrated, have ill-defined borders, and are bacteriologically positive; the lepromin test is negative, i.e., the immunologic mechanism of the patient is not responsive to the Mycobacterium leprae infection. Lucio l. an acute form occurring in pure diffuse lepromatous l. presenting irregularly shaped, intensely erythematous, tender plaques, especially of the legs, with tendency to ulceration and scarring. SYN: Lucio l. phenomenon. macular l. a form of tuberculoid l. in which the lesions are small, hairless, and dry, and are erythematous in light skin and hypopigmented or copper-colored in dark skin. mutilating l. a late stage of anesthetic l.. nodular l. SYN: tuberculoid l.. smooth l. SYN: tuberculoid l.. trophoneurotic l. SYN: anesthetic l.. tuberculoid l. a benign, stable, and resistant form of the disease in which the lepromin reaction is strongly positive and in which the lesions are erythematous, insensitive, infiltrated plaques with clear-cut edges. SYN: nodular l., smooth l..

leprotic (lep-rot′ik)
SYN: leprous.

leprous (lep′rus)
Relating to or suffering from leprosy. SYN: leprotic.

-lepsis, -lepsy
A seizure. [G. lepsis]

leptandra (lep-tan′dra)
Dried rhizome and roots of Veronicastrum virginicum (family Serophulariaceae). Indigenous to North America. Formerly used as a cathartic. SYN: black root, Culver root.

leptin (lep′tin)
A helical protein secreted by adipose tissue and acting on a receptor site in the ventromedial nucleus of the hypothalamus to curb appetite and increase energy expenditure as body fat stores increase. L. levels are 40% higher in women, and show a further 50% rise just before menarche, later returning to baseline levels; levels are lowered by fasting and increased by inflammation. [G. leptos, thin, + -in] Human genes encoding both l. (locus 7q31.3) and the l. receptor site (1p31) have been identified. Laboratory mice having mutations on the ob gene, which encodes l., become morbidly obese, diabetic, and infertile; administration of l. to these mice improves glucose tolerance, increases physical activity, reduces body weight by 30%, and restores fertility. Mice with mutations of the db gene, which encodes the l. receptor, also become obese and diabetic but do not improve with administration of l.. Although mutations in both the l. and l. receptor genes have been found in a small number of morbidly obese human subjects with abnormal eating behavior, the majority of obese persons do not show such mutations, and have normal or elevated circulating levels of l.. L. enhances insulin-mediated glucose transport into adipose cells in vitro. In preliminary trials, both lean and overweight persons have shown modest weight loss with daily subcutaneous injections of recombinant methionyl human l. over several months. All subjects followed weight-reduction diets during the trial period. Weight loss in some subjects receiving l. did not exceed that achieved by subjects receiving placebo, but when significant weight reduction occurred, it was proportionate to dosage. The immune deficiency seen in starvation may result from diminished l. secretion. Mice lacking the gene for l. or its receptor show impairment of T-cell function, and in laboratory studies l. has induced a proliferative response in human CD4 lymphocytes.

Light, thin, frail. [G. leptos, slender, delicate, weak]

leptocephalous (lep-to-sef′a-lus)
Having an abnormally tall, narrow cranium. [lepto- + G. kephale, head]

leptocephaly (lep-to-sef′a-le)
A malformation characterized by an abnormally tall, narrow cranium. [lepto- + G. kephale, head]

leptochromatic (lep′to-kro-mat′ik)
Having a very fine chromatin network.

leptocyte (lep′to-sit)
A target or Mexican hat cell, i.e., an unusually thin or flattened red blood cell in which there is a central rounded area of pigmented material, a middle clear zone that contains no pigment, and an outer pigmented rim at the edge of the cell. Leptocytes are thought to be erythrocytes in which the cellular envelope or membrane is unusually large in proportion to its contents. [lepto- + G. kytos, cell]

leptocytosis (lep′to-si-to′sis)
The presence of leptocytes in the circulating blood, as in thalassemia, some instances of jaundice (even in the absence of anemia), occasional examples of hepatic disease (in the absence of jaundice), and some patients who have had the spleen removed.

leptodactylous (lep-to-dak′ti-lus)
Having slender fingers. [lepto- + G. daktylos, finger]

leptomeningeal (lep′to-me-nin′je-al)
Pertaining to the leptomeninges.

leptomeninges, leptomeninx, gen. leptomeninx (lep-to-me-nin′jez, lep′to-me′ninks, lep′to-me′ninks) [TA]
SYN: leptomeninx. [lepto- + G. meninx, pl. meninges, membrane]

leptomeningitis (lep′to-men-in-ji′tis)
Inflammation of leptomeninges. SEE ALSO: arachnoiditis. SYN: pia-arachnitis. basilar l. inflammation of the arachnoid at the base of the brain; often found in chronic meningitis of tuberculous, luetic, or mycotic origin.

leptomere (lep′to-mer)
A very minute particle of living matter; Asclepiades believed the body was composed of an aggregation of vast numbers of leptomeres. [lepto- + G. meros, part]

leptomonad (lep′to-mo′nad, lep-tom′o-nad)
1. Common name for a member of the genus Leptomonas. 2. See promastigote.

Leptomonas (lep′to-mo′nas, lep-tom′o-nus)
A genus of asexual, monogenetic, parasitic flagellates (family Trypanosomatidae) commonly found in the hindgut of insects. [lepto- + G. monas, unit]

leptonema (lep-to-ne′ma)
SYN: leptotene. [lepto- + G. nema, thread]

leptophonia (lep′to-fo′ne-a)
SYN: hypophonia. [lepto- + G. phone, sound, voice]

leptophonic (lep′to-fon′ik)

leptopodia (lep-to-po′de-a)
The condition of having slender feet. [lepto- + G. pous, foot]

leptoprosopia (lep′to-pro-so′pe-a)
Narrowness of the face. [lepto- + G. prosopon, face]

leptoprosopic (lep′to-pro-so′pik)
Having a thin, narrow face. Cf.:leptosomatic.

leptorrhine (lep′to-rin)
Having a thin nose. Applied to a skull with a nasal index below 47 (Frankfort agreement) or 48 (Broca). [lepto- + G. rhis, nose]

leptoscope (lep′to-skop)
An apparatus for measuring cell membranes.

leptosomatic, leptosomic (lep′to-so-mat′ik, -to-so′mik)
Having a slender, light, or thin body. [lepto- + G. soma, body]

Leptospira (lep′to-spi′ra)
A genus of motile aerobic bacteria (order Spirochaetales) containing thin, tightly coiled organisms 6–20 μm in length. They possess an axial filament, and one or both ends may be bent into a semicircular hook. They stain with difficulty except with Giemsa stain or silver impregnation. Associated with icterohemorrhagic fever. They include 7 pathogens and 3 nonpathogenic species; the type species is L. interrogans. [lepto- + G. speira, a coil] L. interrogans a species containing multiple named pathogenic serovars. Causative agent of leptospirosis. It is the type species of the genus L..

leptospire (lep′to-spir)
Common name for any organism belonging to the genus Leptospira.

leptospirosis (lep′to-spi-ro′sis)
Infection with Leptospira interrogans. anicteric l. infection with one of the species of the Leptospira group, usually mild, with limited liver and kidney involvement, as opposed to Weil disease. l. icterohemorrhagica (ik′ter-o-hem-or-aj′i-ka) SYN: icterohemorrhagic fever.

leptospiruria (lep′to-spi-roo′re-a)
Presence of species of the genus Leptospira in the urine, as a result of leptospirosis in the renal tubules.


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