Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «L»:
Library, cDNA: A collection of DNA sequences generated from mRNA (messenger RNA) sequences. This type of DNA library contains only DNA that codes for proteins and does not include any non-coding DNA....
Library, genomic: A collection of DNA clones made from
a set of randomly generated overlapping DNA fragments representing the entire genome of an
organism. As a molecular genetic sequel to John Steinbeck's "Of Mice and
Men", today you can have a mouse genomic library or a human genomic lib...
Lice, head: See: Head lice....
Lice, pubic: See: Pubic lice....
Licensed clinical social worker
Licensed clinical social worker: A social worker trained in psychotherapy who helps individuals deal with a variety of mental health and daily living problems to improve overall functioning. A social worker usually has a master's degree in social work and has studied sociology, growth and developmen...
Lichen planus: A common skin disease with small itchy pink or purple spots on the arms or legs.
The lesions (abnormal areas) on the skin in lichen planus are typically polygonal, flat (hence, the term planus), and pruritic (itchy). Occurs characteristically on the wrists, shins, lower back and genit...
Lichenification: Thick, leathery skin, usually the result of constant scratching and rubbing.
With prolonged rubbing or scratching, the outer layer of the skin (the epidermis) becomes hypertrophied (overgrown) and this results in thickening of the skin and exaggeration of the normal skin markings, g...
Lichtenberg figures: A fern-leaf pattern of reddish, painless marks on the skin that are a result of a skin reaction to a lightening strike. The pattern typically vanishes in a few hours or days.
Lichtenberg figures are named after Georg Christoph Lichtenberg, a German physicist, who described simil...
Life support: 1. A therapy or device designed to preserve someone's life when an essential bodily system is not doing so. Life support may, for example, involve enteric feeding (by a tube), total parenteral nutrition, mechanical ventilation, a pacemaker, defibrillator, heart/lung machine, or dialysi...
Lifestyle disease: A disease associated with the way a person or group of people lives. Lifestyle diseases include atherosclerosis, heart disease, and stroke; obesity and type 2 diabetes; and diseases associated with smoking and alcohol and drug abuse. Regular physical activity helps prevent obesity...
Lifetime risk: The risk of developing a disease during ones lifetime or dying of the disease. The estimated lifetime risk of developing diabetes for individuals born in 2000 in the US is 32.8% for males and 38.5% for females. Women who inherit mutations of the BRCA1 or BRCA2 gene are at an 82% lifet...
Ligament: A ligament is a tough band of
connective tissue that connects various structures such as two bones.
"Ligament" is a fitting term; it comes from the Latin "ligare" meaning "to bind or tie."...
Ligament, anterior cruciate
Ligament, anterior cruciate: See: Anterior cruciate ligament....
Ligament, lateral collateral knee
Ligament, lateral collateral knee: The knee joint is surrounded by a joint capsule with ligaments strapping the inside and outside of the joint (collateral ligaments) as well as crossing within the joint (cruciate ligaments). These ligaments provide stability and strength to the knee joint.
Ligament, medial collateral knee
Ligament, medial collateral knee: The knee joint is surrounded by a joint capsule with ligaments strapping the inside and outside of the joint (collateral ligaments) as well as crossing within the joint (cruciate ligaments). These ligaments provide stability and strength to the knee joint.