Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «T»:
Totipotent: Having unlimited capability.
A totipotent cell has the capacity to form an entire organism. Human development begins when a sperm fertilizes an egg and creates a single totipotent cell. In the first hours after fertilization, this cell divides into identical totipotent cells. Approxima...
Tourette syndrome: A tic disorder
characterized by the presence of chronic vocal and motor tics, probably based on differences in or damage to the basal ganglia of the brain.
Tourette syndrome usually emerges between the ages of 6 and 18 and is somewhat more common in people with ADHD (attentio...
Toxaphene: A chlorinated hydrocarbon insecticide currently banned for all uses in the US. Breathing, eating, or drinking high levels of toxaphene can damage the lungs, nervous system, and kidneys, and can even cause death. The US Department of Health and Human Services (DHHS) has determined that tox...
Toxemia: A condition in pregnancy, also known as pre-eclampsia (or preeclampsia) characterized by abrupt hypertension (a sharp rise in blood pressure), albuminuria (leakage of large amounts of the protein albumin into the urine) and edema (swelling) of the hands, feet, and face. Pre-eclampsia is the...
Toxic agent syndrome
Toxic agent syndrome: See: Toxic syndrome....
Toxic goiter, diffuse
Toxic goiter, diffuse: Graves disease, the most common cause of hyperthyroidism (overactivity of the thyroid gland), with generalized diffuse overactivity ("toxicity") of the entire thyroid gland which becomes enlarged into a goiter.
There are three clinical components to Graves disease:
Toxic hepatitis: Hepatitis (inflammation of the liver) caused by an industrial chemical such as carbon tetrachloride or phosphorus....
Toxic multinodular goiter
Toxic multinodular goiter: Condition in
which the thyroid gland contains multiple lumps (nodules) that are overactive, produce
excess thyroid hormones and thereby cause hyperthyroidism. This condition is also known as
Parry's disease or Plummer's disease....
See Toxic shock syndrome....
Toxic shock syndrome
Toxic shock syndrome: A grave condition occurring predominantly in menstruating women
using tampons, toxic shock is characterized by a highly toxic state (with sudden high
fever, vomiting, diarrhea, muscle aching) followed by low blood pressure (hypotension)
which can lead to shock (and death). The...
Toxic syndrome: The ensemble of the signs and symptoms of the disorder resulting from exposure to a toxic agent. There are many toxic syndromes. There is a toxic syndrome for ricin or abrin poisoning; a toxic syndrome for arsine or stibine poisoning; a toxic syndrome for riot control agents; a toxic...
Toxicity: The degree to which a substance can harm humans or
Toxicity can be acute, subchronic, or chronic:
Acute toxicity involves harmful effects in an organism through a single or
Subchronic toxicity is the ability of a toxic substance to cause effects
Toxicogenomics: The collection, interpretation, and storage of information about gene and protein activity in order to identify toxic substances in the environment, and to help treat people at the greatest risk of diseases caused by environmental pollutants or toxicants....
Toxicology: The study of the nature, effects and detection of poisons and the treatment of poisoning....
Toxin: One of a number of poisons produced by
certain plants, animals, and bacteria.
The term "toxin" is frequently used to refer specifically to a
particular protein produced by some higher plants, animals and
pathogenic (disease-causing) bacteria. A toxin typically has a high