T

T Cells
One type of white blood cell that attacks virus infected cells, foreign cells, and cancer cells. T cells are immune system cells that develop in the thymus gland. T cells also produce a number of substances that regulate the immune response. Findings suggest that T cells are implicated in myelin destruction. T cells also called T lymphocyte.

Thymus
An organ that is part of the lymphatic system, in which T lymphocytes grow and multiply. The thymus is in the chest behind the breastbone.

Thyroid Gland
Pronounced – THY-royd
A gland located beneath the voice box (larynx) that produces thyroid hormone. The thyroid helps regulate growth and metabolism.

Tonsil
One of two small masses of lymphoid tissue on either side of the throat.

Tonsillectomy
Surgical removal of the tonsils, usually to treat tonsillitis.

Trachea
The airway that leads from the larynx to the lungs. Also called the windpipe.

Trans Fat
Pronounced – tranz-fat
A type of fat that has certain chemical properties and is usually found in processed foods such as baked goods, snack foods, fried foods, shortening, margarine, and certain vegetable oils. Eating trans fat increases blood cholesterol levels and the risk of heart disease.

Transverse Myelitis
An acute spinal cord disorder causing sudden low back pain and muscle weakness and abnormal sensory sensations in the lower extremities. Transverse myelitis often remits spontaneously, however, severe or long lasting cases may lead to permanent disability.

Tumor
Pronounced – TOO-mer
An abnormal mass of tissue that results from excessive cell division. Tumors perform no useful body function. They may be benign (not cancerous) or malignant (cancerous).