Amino acid, nonessential: An amino acid that can be made by humans and so is not essential to the human diet. There are 11 nonessential amino acids: alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine, and tyrosine.
Aminotransferase: An enzyme that catalyzes the transfer of an amino group from a donor molecule to a recipient molecule. The donor molecule is usually an amino acid and the recipient molecule is usually an alpha-2 keto acid. Two of the best-known enzymes in this class are serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic […]
Amitriptyline: An antidepressant medication. In some patients with depression, abnormal levels of brain chemicals called neurotransmitters may relate to the depression. Amitriptyline elevates mood by raising the level of neurotransmitters in brain tissue. Amitriptyline is also a sedative that is useful for depressed patients with insomnia, restlessness, and nervousness. It is sometimes used to treat […]
AML: Acute myeloid leukemia (also known as acute myelogenous leukemia), a quickly progressive malignant disease in which there are too many immature blood-forming cells in the blood and bone marrow, the cells being specifically those destined to give rise to the granulocytes or monocytes, both types of white blood cells that fight infections. In AML, […]
Ammonia: A colorless gas with a very sharp odor. Made both by humans and by nature, ammonia dissolves easily in water and evaporates quickly. Liquid ammonia is found in many household cleaners. Ammonia is irritating to the skin, eyes, nose, throat, and lungs. Exposure to high concentrations in the air can severely burn the skin, […]
Amnesia: An impairment to or lack of memory. Antegrade amnesia refers to a lack of memory of events occurring after a traumatic event, whereas retrograde amnesia refers to lack of memory of events that occurred before the event.