Webster's New World Medical Dictionary

anatomy, microscopic
The study of normal
structure of an organism under the microscope.
Known among medical students simply as “micro.”
Also known as histology.
anatripsis
The use of friction as a treatment
modality for a medical condition. Anatripsis may or
may not also involve the application of a medicament.
Anderson-Fabry disease
See 
Fabry disease.
androgen
A group of hormones, including
androsterone, that promotes the development and
maintenance of male sex characteristics. Androgen
production is stimulated by the hormone testos-
terone. See also 
testosterone.
android pelvis
See 
male pelvis.
androstenedione
A steroid produced in the
adrenal gland that is a precursor to testosterone and
other male hormones (androgens). Known popu-
larly as andro, it has been used as a supplement to
increase muscle strength. Taking andro raises
testosterone levels above normal. Side effects
include acne, male baldness, and a decrease in
“good” cholesterol (which may predispose to heart
disease and stroke).
androsterone
A male sex hormone that is found
in the blood and urine of men and women. It is
seven times weaker than testosterone.
anemia
The condition of having a lower-than-
normal number of red blood cells or quantity of
hemoglobin. Anemia diminishes the capacity of the
blood to carry oxygen. Patients with anemia may feel
tired, fatigue easily, appear pale, develop palpita-
tions, and become short of breath. Children with
chronic anemia are prone to infections and learning
problems. The main causes of anemia are bleeding,
hemolysis (excessive destruction of red blood
cells), underproduction of red blood cells (as in
bone marrow diseases), and underproduction of
normal hemoglobin (as in sickle cell anemia and in
iron deficiency anemia). Women are more likely
than men to have anemia because of menstrual
blood loss. In children, anemia is most commonly
due to insufficient iron in the diet. Anemia is also
often due to gastrointestinal bleeding caused by
medications, including such common drugs as
aspirin and ibuprofen.