|| ANATOMY || DISEASES || DRUGS || HEALTH TOPICS || USA HEALTH STATS || CHINA HEALTH STATS || GENOMICS || LABORATORY MICE || LUPUS ||
Medical Dictionary banner
Medical Dictionary - Dictionary of Medicine and Human Biology


Medical Dictionary


A B C D E F G H I J K L M N O P Q R S T U V W X Y Z


laminagraph (lam′i-na-graf)
A device for laminagraphy; a laminagram.

laminagraphy, laminography (lami-nahg′ra-fe, lam-i-nog′-ra-fe)
Radiographic technique in which the images of tissues above and below the plane of interest are blurred out by reciprocal movement of the x-ray tube and film holder, to show a specific area more clearly. SEE ALSO: tomography. [lamina + G. graphe, a writing]

laminar (lam′i-nar)
1. Arranged in plates or laminae. SYN: laminated. 2. Relating to any lamina.

laminaria (lam-i-na′re-a)
Sterile rod made of kelp (genus L.) which is hydrophilic, and, when placed in the cervical canal, absorbs moisture, swells, and gradually dilates the cervix. [L. lamina, a blade]

laminarin (lam-i-nar′in)
An algal polysaccharide, made up chiefly of β-d-glucose residues, obtained from Laminaria species (family Laminariaceae); variable proportions of the glucose chains contain at the potential reducing end a molecule of mannitol that can be sulfated. l. sulfate l. sulfated to varying degrees; two sulfate groups per glucose unit result in maximum stability and anticoagulant activity similar to that of heparin; l. with fewer sulfate groups has only antilipemic activity.

laminated (lam′i-nat-ed)
SYN: laminar (1) .

lamination (lam-i-na′shun)
1. An arrangement in the form of plates or laminae. 2. Embryotomy by removing the fetal head in slices.

laminectomy (lam′i-nek′to-me)
Excision of a vertebral lamina; commonly used to denote removal of the posterior arch. [L. lamina, layer, + G. ektome, excision]

laminin (lam′i-nin)
A large multimeric glycoprotein component of the basement membrane; particularly its unstained laminae; a major protein component of the laminae of the renal glomerulus.

laminitis (lam-i-ni′tis)
Inflammation of any lamina.

laminography (lam-i-nog′-ra-fe)
See laminagraphy.

laminotomy (lam-′i-not′o-me)
Excision of a portion of a vertebral lamina in which the intervertebral foramen is enlarged by removal of a portion of the lamina. SYN: rachiotomy. [L. lamina, layer, + G. tome, incision]

lamins (lam′inz)
Fibrous network associated with the inner membranes of cell nuclei, composed of polypeptides of varying molecular weights (60,000–80,000) and classified as A, B, C, etc. on the basis of physical properties; the phosphorylation of l. is associated with mitosis.

lamotrigine (la-mo′tri-jen)
New structural class of antiepileptics; an anticonvulsant which appears in preclinical studies to resemble phenytoin.

lamp (lamp)
Illuminating device; source of light. SEE ALSO: light. annealing l. an alcohol l. with a soot-free flame used in dentistry to drive off the protective NH3 gas coating from the surface of cohesive gold foil. Edridge-Green l. a lantern used to test recognition of colored signals; it displays a single light with color filters in rotating disks that can be modified to simulate conditions of weather and atmosphere. This test for color blindness was officially adopted in Great Britain in 1915 in place of the Holmgren wool test, but is now seldom used. heat l. a l. that emits infrared light and produces heat; used to apply topical heat to the skin. mercury vapor l. a l. in which the electric arc is in an ionized mercury vapor atmosphere; it produces ultraviolet light that can be used therapeutically or in diagnostic photometry. mignon l. a minute electric light used in various endoscopic instruments. slit l. a combination of a microscope and a narrow beam of collimated light, used to examine the eye. spirit l. a l., used mainly for heating in laboratory work, in which alcohol is burned. tungsten arc l. a l. having highly compressed tungsten elements. ultraviolet l. a l. that emits rays in the ultraviolet band of the spectrum. SEE ALSO: ultraviolet. Wood l. an ultraviolet l. with a nickel oxide filter that only passes light with a maximal wavelength of about 3660 Å; used to detect by fluorescence hairs infected Microsporum audouinii, M. canis, var. distortum, or M. ferrugineum, producing greenish-yellow fluorescence.

Lamy
Maurice, French physician, 1895–1975. See Maroteaux-L. syndrome.

lana, gen. and pl. lanae (lan′a, lan′e)
SYN: wool. [L.]

lanatoside D (la-nat′o-sid)
A digitalis glycoside from the leaves of Digitalis lanata, yielding the genin diginatigenin (12-hydroxygitoxigenin; 16-hydroxydigoxigenin).

lanatosides A, B, and C (la-nat′o-sidz)
Digilanides A, B, and C; the cardioactive precursor glycosides obtained from Digitalis lanata. Removal of the acetyl group yields desacetyllanatosides A, B, and C (purpurea glycosides A, B, and C, respectively); removal of the glucose from lanatosides A, B, and C yields acetyldigitoxin, acetylgitoxin, and acetyldigoxin, respectively; removal of glucose and the acetyl group yields digitoxin, gitoxin, and digoxin, respectively. SEE ALSO: purpurea glycosides A.

lance (lans)
1. To incise a part, as an abscess or boil. 2. A lancet. [L. lancea, a slender spear]

Lancefield
Rebecca Craighill, U.S. bacteriologist, 1895–1981. See L. classification.

lancet (lan′set)
A surgical knife with a short, wide, sharp-pointed, two-edged blade. [Fr. lancette] gum l. a l. used for incising the gum over the crown of an erupting tooth. spring l. a l. with a handle containing a blade that is activated by a spring. thumb l. a l. with short flat blade that folds back, when closed, between two plates of the handle.

lancinating (lan′si-nat′ing)
Denoting a sharp cutting or tearing pain. [L. lancino, pp. -atus, to tear]

Lancisi
Giovanni M., Italian physician, 1654–1720. See L. sign, striae l., under stria.

Landau-Kleffner syndrome
See under syndrome.

Landouzy
Louis T.J., French neurologist, 1845–1917. See L.-Dejerine dystrophy, L.-Grasset law.

Landry
Jean B.O., French physician, 1826–1865. See L. paralysis, L. syndrome, L.-Guillain-Barré syndrome.

Landschutz tumor
See under tumor.

Landsteiner
Karl, Austrian-U.S. pathologist and Nobel laureate, 1868–1943. See L.-Donath test, Donath-L. cold autoantibody, Donath-L. phenomenon.

Landström
John, Swedish surgeon, 1869–1910. See L. muscle.

Landzert
T., 19th century German anatomist. See L. fossa, Gruber-L. fossa.

Lane
Sir William Arbuthnot, English surgeon, 1856–1943. See L. band, L. disease.

Lang
Basil T., English ophthalmologist, 1880–1928.

Lange
Carl F.A., German biochemist, *1883. See L. solution, L. test.

Lange
Cornelia de. See under de L..

Langenbeck
Bernhard R.K. von, German surgeon, 1810–1887. See L. triangle.

Langendorff
Oscar, German physiologist, 1853–1908. See L. method.

Lange-Nielsen
F., 20th century Norwegian cardiologist. See Jervell and Lange-Nielsen syndrome.

Langer
Carl (Ritter von Edenberg), Austrian anatomist, 1819–1887. See L. arch, L. lines, under line, L. muscle.

Langer
Leonard O., American physician. See L.-Saldino syndrome.

Langerhans
Paul, German anatomist, 1847–1888. See L. cells, under cell, L. granule, L. islands, under island, islets of L., under islet.

Langhans
Theodor, German pathologist, 1839–1915. See L. cells, under cell, L.-type giant cells, under cell, L. layer, L. stria.

Langley
John N., English physiologist, 1852–1925. See L. granules, under granule.

Langmuir
Irving, U.S. chemist and Nobel laureate, 1881–1957. See L. trough.

language (lang′gwij)
The use of spoken, manual, written, and other symbols to express, represent, or receive communication. [L. lingua] American Sign L. (ASL) the manual sign and gesture l. used by the deaf community in the United States. It is a l. distinct from English, with its own grammar and syntax, but no written form. body l. 1. the expression of thoughts and feelings by means of nonverbal bodily movements, e.g., gestures, or via the symptoms of hysterical conversion; See kinesics. 2. communication by means of bodily signs.

laniary (lan′i-ar-e)
Adapted for tearing; in anatomy, sometimes applied to canine teeth, as l. teeth. [L. lanio, to tear to pieces]

lankamycin (lan′ka-mi-sin)
Macrolide antibiotic produced by Streptomyces violaceoniger from the soil of Sri Lanka.

Lannelongue
Odilon M., French surgeon and pathologist, 1840–1911. See L. foramina, under foramen, L. ligaments, under ligament.

lanolin (lan′o-lin)
SYN: adeps lanae. [L. lana, wool, + oleum, oil] anhydrous l. l. that contains not more than 0.25% of water; used as a water-adsorbable ointment base.

lanosterol (lan-o′ster-ol)
A zoosterol synthesized from squalene and a precursor to cholesterol.

Lanterman
A.J., 19th century U.S. anatomist in Strasbourg. See L. incisures, under incisure, L. segments, under segment, Schmidt-L. clefts, under cleft, Schmidt-L. incisures, under incisure.

lanthanic (lan′tha-nik)
Rarely used term denoting a disease process that produces no symptoms or clinical evidence of illness. [G. lanthano, to lie hidden]

lanthanides (lan′tha-nidz)
Those elements with atomic numbers 57–71 that closely resemble one another chemically and were once difficult to separate from one another. SYN: rare earth elements. [lanthanum, first element of the series]

lanthanum (La) (lan′tha-num)
A metallic element, atomic no. 57, atomic wt. 138.9055; first of the rare earth elements (lanthanides). [G. lanthano, to lie hidden] l. nitrate La(NO3)3;used in electron microscopy as a stain for extracellular mucopolysaccharides.

lanthionine (lan-thi′o-nen)
3,3′-Thiodialanine;an amino acid obtained from wood that resembles cystine but has only one sulfur atom in the molecule rather than two; i.e., a sulfide rather than a disulfide.

lanugo (la-noo′go) [TA]
SYN: downy hair. [L. down, wooliness, from lana, wool]

Lanz
Otto, Swiss surgeon in Amsterdam, 1865–1935. See L. line.

LAO
Abbreviation for left anterior oblique projection, used in chest radiography, especially to assess the size of the left atrium and ventricle.

LAP
Abbreviation for leukocyte alkaline phosphatase. See alkaline phosphatase.

laparo-
The loins (less properly, the abdomen in general). [G. lapara, flank, loins]

laparocele (lap′a-ro-sel)
SYN: abdominal hernia. [laparo- + G. kele, hernia]

laparoendoscopic (lap′a-ro-en-do-skop′ik)
Having to do with the introduction of a laparoscope into the abdominal cavity for a variety of intracavitary procedures.

laparogastroscopy (lap′a-ro-gas-tros′ko-pe)
Inspection of interior of the stomach after a gastrotomy. [laparo- + G. gaster, stomach, + skopeo, to view]

laparomyositis (lap′a-ro-mi′o-si′tis)
Inflammation of the lateral abdominal muscles. [laparo- + G. mys, muscle, + -itis, inflammation]

laparorrhaphy (lap′a-ror′a-fe)
SYN: celiorrhaphy.

laparosalpingo-oophorectomy (lap′a-ro-sal′ping-go-o-of′o-rek′to-me)
Removal of the uterine tube and ovary through an abdominal incision.

laparoscope (lap′a-ro-skop)
An endoscope for examining the peritoneal cavity. SYN: peritoneoscope. [laparo- + G. skopeo, to view]

laparoscopy (lap-a-ros′ko-pe)
Examination of the contents of the abdominopelvic cavity with a laparoscope passed through the abdominal wall. SEE ALSO: peritoneoscopy. SYN: abdominoscopy.L. first became clinically practicable with the development of fiberoptics in the 1960s and of high-intensity, low-heat halogen bulbs in the 1970s. The technique has become standard, in selected cases, for many routine surgical procedures formerly requiring laparotomy, such as appendectomy, cholecystectomy, inguinal herniorrhaphy, oophorectomy, a second look after excision of an ovarian tumor, and diagnostic evaluation of endometriosis and female infertility. The peritoneal cavity is first inflated with CO2 gas, and the laparoscope passed through a small incision in the abdominal wall. A second incision is usually required to provide surgical access to the area of interest. An elaborate armamentarium of surgical instruments has been developed to perform incision, drainage, excision, cautery, ligation, suturing, and other procedures with the laparoscope. The risk of intraoperative and postoperative complications, the cost of treatment, and hospitalization time are generally less with laparoscopic surgery than with traditional open procedures. closed l. l. performed after insufflation of the abdominal cavity using a percutaneously placed needle. open l. l. performed after insufflation of the abdomen using a trocar placed under direct vision after making a small celiotomy incision.

laparotomy (lap′a-rot′o-me)
1. Incision into the loin. 2. SYN: celiotomy. [laparo- + G. tome, incision]

Lapicque
Louis, French physiologist, 1866–1952. See L. law.

lapinization (lap′i-ni-za′shun)
Serial passage of a virus or vaccine in rabbits. [Fr. lapin, rabbit]




A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

. . . Feedback