Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «L»:
Lepra: 1. Leprosy (Hansen disease)
2. Before the mid 19th century, psoriasis.
The acronym LEPRA stands for the Leprosy Relief Association....
Leprosy: See: Hansen disease....
Leptin: A hormone that has a central role in fat metabolism. Leptin was originally thought to be a signal to lose weight but it may, instead, be a signal to the brain that there is fat on the body.
Hugely obese children have been found who have an inability to lose weight due to a genetic inability ...
Leptomeningeal: Having to do with the leptomeninges, the two innermost layers of tissues that cover the brain and spinal cord. Leptomeningeal metastasis refers to cancer that has spread from the original (primary) tumor to the leptomeninges....
Leptomeninges: The two innermost layers of tissues that cover the brain and spinal cord. The two layers are called the arachnoid mater and pia mater....
Leptospirosis: An infectious disease caused by
a particular type of bacteria called a spirochete transmitted by rats as well as by skunks, opossums, raccoons, foxes, and other vermin. Leptospirosis occurs worldwide but is most commonly
acquired in the tropics. About 100 cases of leptospirosis
Lesbian: Female homosexual. The name
"lesbian" comes from the Greek island of Lesbos in the
Aegian Sea where in antiquity the women were said to be
homosexual. The poet Sappho who lived on Lesbos (circa 600 BC) was a
lesbian in both geographic location and sexual orientation....
Lesbian suicide risk
Lesbian suicide risk: High rates of suicide have
consistently been reported among homosexuals, particularly among adolescents and
young adults. A 1989 report concluded that "gay youth are 2 to 3 times more likely to attempt suicide than other young people. They may comprise up to 30% of completed ...
Lesbianism: Female homosexuality. Also called sapphism (after the
lesbian poet Sappho)....
Lesion: Pronounced "lee-sion" with the emphasis on
the "lee," a lesion can be almost any abnormality involving any
tissue or organ due to any disease or any injury.
There are, not surprisingly, many types of lesions. There are also a number of different ways of classifying and naming lesions.
Let down reflex
Let down reflex: An involuntary reflex during breastfeeding which
causes the milk to flow freely....
Lethal: Deadly, fatal, capable of causing death, death-dealing. The word "lethal" comes from the Latin "letum" meaning "death or destruction."...
Lethal gene, zygotic
Lethal gene, zygotic: A gene that is lethal (fatal) for the zygote, the cell formed by the union of a sperm (male sex cell) and an ovum (female sex cell). The zygote would normally develop into an embryo, as instructed by the genetic material within the unified cell. However, a zygotic lethal gene ...
Lethargy: 1. Abnormal drowsiness, stupor. 2. A state of indifference. From the Greek lethargia, drowsiness....
Letrozole: An oral antiestrogen. Letrozole inhibits the enzyme aromatase in the
adrenal glands that produces the estrogens (estradiol and estrone) and thereby lowers their levels. The brand name of letrozole is Femara.
See also: Aromatase inhibitor; monograph on Femara (letrozole)....