Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «N»:
n-Hexane: A chemical made from crude oil that is mixed with solvents for a number of uses. Inhaling n-hexane causes nerve damage and paralysis of the arms and legs. Some people abuse products containing n-hexane by inhaling it to get "high."
Most of the n-hexane used in industry is mixed with sim...
N-nitroso-fenfluramine: A variant of fenfluramine. See: Fenfluramine....
Na (sodium): Na is the chemical symbol for sodium.
From natrium, a
synonym for sodium.
Sodium is the major positive ion (cation) in fluid outside of
cells. The chemical notation for sodium is Na+. When
combined with chloride (Cl), the resulting substance is table salt
(NaCl). Excess sodium (su...
Nadir:The lowest point as, for example, the lowest blood count after chemotherapy, the lowest concentration of a drug in the body, etc....
Naegleria fowleri: A protozoa that is a pathogenic free-living ameba. Infection with Naegleria fowleri causes primary amebic meningoencephalitis....
Naegleria infection: Infection from an ameba called Naegleria fowleri that is commonly found in the environment, in water and soil. It is found worldwide, most commonly in warm bodies of fresh water, such as lakes, rivers, and hot springs; warm water discharge from industrial plants; and under-chlor...
Nail: In medicine, there are two types of nails. One is
just a plain old metal nail used to hold 2 or more pieces of bone together, for example,
after a fracture. The other type of nail is the horny plate on the end of the finger or
toe. Each nail anatomically has a body, lateral nail folds (on the ...
Nail care: Care of the fingernails and toenails. Many nail problems are due to poor nail care. Recommendations for maintaining nail health include keeping nails clean and dry to keep bacteria and other infectious organisms from collecting under the nails, cutting nails straight across with only sli...
Nail cross furrows
Nail cross furrows: See: Beau's lines....
Nail dysgenesis and hypodontia
Nail dysgenesis and hypodontia: A genetic disorder characterized by abnormalities of the nails (nail dysgenesis) and the absence of several teeth (hypodontia) at birth. The disorder is also known as Witkop syndrome or as the tooth and nail syndrome (TNS).
The tooth and nail defects in the syndrom...
Nail furrows: See: Beau's lines....
Nail grooves: See: Beau's lines....
Nail infection, fungal
Nail infection, fungal: The most
common fungus infection of the nails is onychomycosis.
Onychomycosis makes the nails look white and opaque, thickened,
and brittle. Those at increased risk for developing onychomycosis
People with diabetes;
People with disease of the small blood vessels
Nail lines: See: Beau's lines....
Nail-patella syndrome: An hereditary condition characterized by abnormally formed or absent nails and underdeveloped or absent kneecaps (patellae). Other features include:
Abnormality of the elbows interfering with full range of motion
(pronation and supination)
Kidney disease resembl...