Webster's New World Medical Dictionary

National Institute on Aging (NIA)
The NIA leads a national program of
research on the biomedical, social, and
behavioral aspects of the aging process;
the prevention of age-related diseases
and disabilities; and health promotion for
older Americans.
•
National Institute on Alcohol Abuse
and Alcoholism (NIAAA)
The NIAAA
conducts research into improving the
treatment and prevention of alcoholism
and alcohol-related problems.
•
National Institute on Deafness and
Other Communication Disorders
(NIDCD)
The NIDCD conducts and
supports biomedical research and
research training on normal mechanisms
as well as diseases and disorders of hear-
ing, balance, smell, taste, voice, speech,
and language.
•
National Institute on Drug Abuse
(NIDA)
The NIDA conducts and sup-
ports research on the causes, prevention,
and treatment of drug abuse and addiction.
•
National Library of Medicine (NLM)
The world’s largest medical library, the
NLM collects, organizes, and makes avail-
able biomedical science information to
investigators, educators, and practition-
ers. It also carries out programs to
strengthen medical library services in the
US. Its electronic databases, including
MEDLINE, are used extensively through-
out the world.
•
NIH Clinical Center
As the clinical
research facility of NIH, this center pro-
vides the patient care, services, and facili-
ties to support human subjects research
by the NIH. Also known as the National
Institutes of Health Clinical Center
(NIHCC).
natriuresis
The excretion of an excessively large
amount of sodium in the urine. Natriuresis is simi-
lar to diuresis (the excretion of an unusually large
quantity of urine), except that in natriuresis the
urine has an exceptionally high salt concentration.
Natriuresis occurs with some diuretics and diseases
(as of the adrenal gland) and can lead to the salt-
losing syndrome characterized by dehydration,
vomiting, low blood pressure, and the risk of sud-
den death. See also 
diuresis.
natriuretic
An agent or disease that promotes
natriuresis. For example, a diuretic with natriuretic
action could be helpful for someone retaining water
and salt. See also 
diuretic.