Atrophy

A wasting of tissues, organs, or the entire body. Muscle atrophy can be caused by lack of physical exercise (Disuse atrophy), and can be reversed by exercise. But the second and most severe type of muscle atrophy is neurogenic atrophy. It occurs when there is injury...

Attenuation

A decrease in vitality or pathogenicityof a microorganism or in the severity of a disease. In radiology; the loss of energy of a beam of radiant energy due to absorption, scattering, beam divergence, and other causes as the beam propagates through a...

Audiometry

A test to measure hearing. An audiology exam tests the ability to hear sounds by intensity (volume or loudness) and tone (the speed of sound wave vibrations). Sound waves move to the nerves of the inner ear and then the brain and can travel to the inner ear by air...

Autosomes

Those chromosomes which are not the sex chromosomes. In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Twenty-two of these pairs, called autosomes, look the same in both males and females. The 23rd pair, the sex chromosomes, differ...

Axillary Lymph Nodes

Lymph nodes in the armpit region that drains lymph channels from the breast. Numerous nodes around the axillary (below the shoulder joint) veins which receive the lymphatic drainage from the upper limb, scapular region and pectoral region (including mammary gland);...

Bacteria

Single-celled microorganisms. Bacteria are single-celled microorganisms which can exist either as independent organisms or as parasites (dependent upon another organism for existance). Examples of bacteria are Acidophilus, Chlamydia, Clostridium welchii or gangrene,...

Benign

Not malignant, not cancerous. In reference to a tumor; an abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancerous), or malignant (cancerous).

BIA

Bioelectric impedance. A non-invasive technique for measuring body composition. Bioelectric impedance analysis is a method for determining the lean body mass. One type of BIA involves standing on a special scale with footpads while a small amount of electrical current...