Medical terms - Letter T | MedicalVocabulary.org

T (thymine)

In genetics, T stands for thymine, one member of the A-T (adenine-thymine) base pair in DNA. The other base pair in DNA is G-C (guanine-cytosine). Each base pair forms a 'rung of the DNA ladder.' A DNA nucleotide is…
T cell

A type of white blood cell that is of key importance to the immune system and is at the core of adaptive immunity, the system that tailors the body's immune response to specific pathogens. The T cells are like soldiers…
T cell, peripheral

A T cell found in the peripheral blood rather than in the lymphatic system.
T lymphocyte, cytotoxic

See: Cytotoxic T-lymphocyte
T-4 cell

A type of T cell that has CD4 markers on its surface and participates in the immune response by recognizing foreign antigens and secreting substances called cytokines that activate T and B cells. T-helper cells fall…
T-4 count

A test that counts the number of T- 4 cells in the blood, usually to assess the immune status of a patient with the HIV virus (AIDS). It's important to note that there are also T-4 cells in the lymphatic system, and…
T-8 cells

T cells that express the CD8 transmembrane glycoprotein (CD8+ T cells). They close down the immune response after invading organisms are destroyed. Suppressor T cells are sensitive to high concentrations of circulating…
T-cell depletion

A disease in which certain cells of the lymphoid system called T lymphocytes or T cells are malignant. T cells are white blood cells that normally can attack virus-infected cells, foreign cells, and cancer cells and…
T-cell leukemia

A disease in which certain cells of the lymphoid system called T lymphocytes or T cells are malignant. T cells are white blood cells that normally can attack virus-infected cells, foreign cells, and cancer cells and…
T-cell lymphoma

A disease in which cells in the lymphoid system called T cells (or T lymphocytes) become malignant. T-cell lymphomas account for a minority (about 15%) of non-Hodgkin lymphomas in the US and are more common in Asia. The…
T-cell receptor

A device used by T cells for recognizing specific antigens. T cells have receptors that are activated exclusively by a target antigen.
T-helper cell

A type of T cell that provides help to other cells in the immune response by recognizing foreign antigens and secreting substances called cytokines that activate T and B cells. T-helper cells fall into two main classes…
T-suppressor cell

A type of immune cells, also called T8 cells, these cells close down the immune response after it has destroyed invading organisms. T8 cells are sensitive to high concentrations of circulating lymphokine hormones and…
T-suppressor cells

T cells that express the CD8 transmembrane glycoprotein (CD8+ T cells). They close down the immune response after invading organisms are destroyed. Suppressor T cells are sensitive to high concentrations of circulating…
T-suppressor count

A test that counts the number of T-suppressor (T-8) cells in the bloodstream. It appears that some T-8 cells secrete a substance that can kill the HIV virus, so a high count is believed to be a good indicator for people…
T.i.d. (on prescription)

Seen on a prescription, t.i.d. means three times a day. It is an abbreviation for 'ter in die' which in Latin means three times a day. The abbreviation t.i.d. is sometimes written without a period either in lower-case…
T1-T12 (thoracic vertebrae)

The symbols T1 through T12 represent the 12 thoracic vertebrae. The thoracic vertebrae are situated between the cervical (neck) vertebrae and the lumbar vertebrae. The thoracic vertebrae provide attachment for the ribs…
T4

Thyroxine, a thyroid hormone. The number 4 is sometimes in subscript
Tabes dorsalis

Slowly progressive degeneration of the spinal cord that occurs in the tertiary (third) phase of syphilis a decade or more after originally contracting the infection. Among the terrible features of tabes dorsalis are…
Table

An old-fashioned but convenient household measure of capacity. A tablespoon holds about 3 teaspoons, each containing about 5 cc, so a tablespoon = about 15 cc of fluid.
Tablespoon

An old-fashioned but convenient household measure of capacity. A tablespoon holds about 3 teaspoons, each containing about 5 cc, so a tablespoon = about 15 cc of fluid
Tablet

In pharmacy, a medication, usually mixed with a binder powder, molded and pressed into the form of a tablet, traditionally circular or disk-shaped, but more recently also oblong or differently shaped. From the French…
Tablet splitter

A device for tablet splitting
Tablet splitting

The practice of cutting tablets in half. The reason is usually financial. To reduce costs, a physician may prescribe pills that have twice the dose a patient needs and then ask the patient to split the pills in half. To…
Tabun

>Runny nose >Watery eyes >Small, pinpoint pupils >Eye pain >Blurred vision >Drooling and excessive sweating >Cough >Chest tightness >Rapid breathing >Diarrhea >Increased urination >Confusion >Drowsiness >Weakness…
TACE

Transarterial chemoembolization, a procedure in which the blood supply to a tumor is blocked (embolized) and chemotherapy is administered directly into the tumor. Used to treat liver cancer
Tache noire

Black spot (in French), a small ulcer covered with a black crust at the site of a tick bite, characteristic of several tick-borne rickettsial diseases.
Tachycardia

A rapid heart rate, usually defined as greater than 100 beats per minute. The tachycardias include sinus tachycardia, paroxysmal atrial tachycardia (PAT), and ventricular tachycardia. Sinus tachycardia is due to rapid…
Tachycardia, paroxysmal atrial

A fast heartbeat (tachycardia) because of rapid firing of the sinoatrial (sinus) node. The sinoatrial (or sinus) node is the natural pacemaker of the heart. It is located in the wall of the right atrium (the right upper…
Tachycardia, sinus

A fast heartbeat (tachycardia) because of rapid firing of the sinoatrial (sinus) node. The sinoatrial (or sinus) node is the natural pacemaker of the heart. It is located in the wall of the right atrium (the right upper…
Tachycardia, ventricular

An abnormally rapid heart rhythm that originates from a ventricle, one of the lower chambers of the heart. Although the beat is regular, ventricular tachycardia is life-threatening because it can lead to a dreaded…
Tachypnea

(Pronounced tack-ip-nea.) Abnormally fast breathing. A respiratory rate that is too rapid. The normal rate of respirations (breaths per minute) depends on a number of factors, including the age of the individual and the…
Tacrolimus

Tacrolimus: A drug that suppresses the immune system and prevents transplant rejection. The drug acts by inhibiting the activation of T cells. The brand name of tacrolimus is Prograf and the brand name of tacrolimus…
Tactile

Having to do with touch
Tactile device

A mechanical instrument that makes use of touch to help individuals who have certain disabilities, such as deaf-blindness, to communicate
Taenia

In medicine, taenia is a genus (group) of large tapeworms some of which are parasitic in humans. In anatomy, taenia refers to a band or a structural line and applies to several bands and lines of nervous matter in the…
Taenia armata

Taenia solium
Taenia asiatica

Taenia solium.
Taenia dentata

Taenia solium
Taenia saginata

The beef tapeworm. The most common of the big tapeworms that parasitizes people, contracted from infected raw or rare beef. Can grow to be 12-25 feet (3.6-7.5 m) long in the human intestine. Also known as the African…
Taenia solium

The pork tapeworm. Contracted from eating undercooked or measly pork (pork infected with the larval forms of the tapeworm). Taenia solium causes two different diseases -- taeniasis and cysticercosis. Taeniasis develops…
Taeniasis

Common minor anomaly, a rudimentary tag of ear tissue, often containing a core cartilage, usually located just in front of the ear (auricle). Therefore, also called preauricular tag. The presence of 2 or more minor…
Tag, ear

Common minor anomaly, a rudimentary tag of ear tissue, often containing a core cartilage, usually located just in front of the ear (auricle). Therefore, also called preauricular tag. The presence of 2 or more minor…
Tag, preauricular

A common minor anomaly, this is a rudimentary tag of ear tissue. It often contains a core of cartilage. The tag is typically located just in front of the ear (auricle) and is therefore called a preauricular tag
Tag, skin

A small tag of skin that may have a stalk (a peduncle). Skin tags may appear on the skin almost anywhere although the favorite locales are the eyelids, neck, armpits (axillae), upper chest, and groin. Invariably benign…
Tail

1. A slender appendage, such as the tail of the pancreas. 2. The appendage that protrudes from the buttocks of animals. People can appear to have a tail due to the presence of supernumerary segments of the coccyx
Tailbone

Popular name for the coccyx, the small bone at the bottom of the spine made up of 3-5 rudimentary vertebrae.
Taint

To poison, infect, or spoil
Takayasu arteritis

Inflammation of aorta and its branches. See: Takayasu disease
Takayasu disease

Takayasu disease: A chronic inflammatory disease of the aorta and its branch arteries. The cause is unknown. The disease is most common in young women of Asian descent and usually begins between 10 and 30 years of age…