Medical terms - Letter T (page 15) | MedicalVocabulary.org

Trisomy

The presence of three copies of a chromosome rather than the normal two. The most common trisomies in newborns are trisomy 13 (Patau syndrome), trisomy 18 syndrome (Edwards syndrome) and trisomy 21 (Down syndrome). The…
Trisomy 13 syndrome

Condition with three rather than the normal two chromosomes #13. Children born with this syndrome have multiple malformations and mental retardation due to the extra chromosome #13. The congenital malformations (birth…
Trisomy 18 syndrome

There are three instead of the normal two chromosomes #18. Children with this condition have multiple malformations and mental retardation due to the extra chromosome #18. The children characteristically have low birth…
Trisomy 21 syndrome

A common chromosome disorder, often called Down syndrome, due to an extra chromosome number 21 (trisomy 21). The chromosome abnormality affects both the physical and intellectual development of the individual. Trisome…
Tritiated

Containing atoms of tritium (hydrogen-3) in the place of hydrogen (H) in a molecule. See also: Tritiated thymidine
Tritium

Hydrogen-3, an isotope of hydrogen. Tritium is a long-lived weak emitter of radiation and can be easily incorporated in large molecules such as DNA, and is therefore much used for autoradiography in the laboratory
TRNA

Transfer RNA
Trocar

A sharply pointed shaft, usually with a three-sided point. A trocar may be used within a cannula, a hollow tube, designed to be inserted into a vein, artery, bone marrow or body cavity. The word trocar is derived from…
Trochanter

One of the bony prominences toward the near end of the thigh bone (the femur). There are two trochanters: > >The greater trochanter: A powerful protrusion located at the proximal (near) and lateral (outside) part of the…
Troche

A small medicated lozenge designed to dissolve. For example, to soothe the throat as a cough drop. Strictly speaking, a troche should be circular since the word derives from the Greek 'trokhiskos' meaning 'a little…
Trochlear nerve

The trochlear nerve controls the superior oblique muscle of the eye, one of the extraocular muscles, the muscles that move the eye. Paralysis of the trochlear nerve results in rotation of the eyeball upward and outward…
Tropical cyclone

A regionally specific name for a strong tropical cyclone in the Southwest Indian Ocean. Other terms for precisely the same type of storm include hurricane (in the North Atlantic Ocean, the Northeast Pacific Ocean east…
Tropical diabetes

Diabetes mellitus associated with chronic malnutrition and, sometimes, chronic pancreatitis. Whether tropical diabetes exists as a distinct entity is under debate. While malnutrition may influence the expression of…
Tropical oil

Coconut, palm kernel or palm oil. Like all fats and oils, these three oils contain various types of fatty acids but, unlike other plant oils, they contain a great deal of saturated fatty acids. Coconut oil is 92%, palm…
Tropical typhus

See Typhus, scrub
Trp

. Tryptophan. See also: Amino acid symbols
True cramp

A cramp that involves part or all of a single muscle or group of muscles that usually act together such as, for example, the muscles that flex adjacent fingers. True cramps are caused by hyperexcitability of the nerves…
True rib

One of the first 7 pairs of ribs. A rib is said to be 'true' if it attaches to the sternum (the breast bone). All 12 pairs of ribs attach to the building blocks of the spine (vertebrae) in the back. The 12 pairs of ribs…
Truncate

To shorten, to cut short. A malformation (birth defect) may truncate a limb. A mutation may create a stop codon that truncates a protein. From the Latin truncare maening to cut short or mutilate from truncus, trunk
Truncation

The act of truncating, cutting short. See: Truncate
Trunk bones

The bones of the human trunk, 51 bones in all, consisting of 26 vertebrae, 24 ribs and the sternum. The 26 vertebrae comprise the 7 cervical, 12 thoracic and 5 lumbar vertebrae, the sacrum and the coccyx. The 24 ribs…
Trunk, pulmonary

See: Pulmonary trunk
Trypanosoma cruzi

The parasitic microorganism that causes Chagas disease. See: Chagas disease
Trypanosomiasis, African

See: African sleeping sickness
Trypanosomiasis, American

See: Chagas disease.
Tryptophan

An amino acid, one of the 20 building blocks of protein. A dietary essential amino acid, tryptophan is necessary for optimal growth of children. Bacteria in the intestine break tryptophan down to compounds that largely…
TSC1

The tuberous sclerosis 1 gene. The product of the TSC1 gene is a protein called hamartin. This protein interacts with tuberin, the product of the TSC2 gene. These two proteins form a complex and play a role in cell…
TSC2

The tuberous sclerosis 2 gene. The product of the TSC2 gene is a protein called tuberin. This protein interacts with hamartin, the product of the TSC1 gene. These two proteins form a complex and play a role in cell…
TSD

Abbreviation for Tay-Sachs disease, a genetic metabolic disorder. See: Tay-Sachs disease
TSE

Abbreviation for Transmissible spongiform encephalopathy
TSH

Stands for thyroid stimulating hormone, a hormone produced by the pituitary gland at the base of the brain in response to signals from the hypothalamus gland in the brain. TSH promotes the growth of the thyroid gland in…
TSH receptor

The receptor for thyroid stimulating hormone (TSH), which is also called thyrotropin. Encoded by a gene on chromosome 14q, TSHR is largest of all known glycoprotein hormone receptors. It is one of the primary antigens…
TSI

Stands for Thyroid Stimulating Immunoglobulin. The TSI level is abnormally high in persons with hyperthyroidism (too much thyroid hormone) due to Graves' disease. Thyroid hormones are essential for the function of every…
Tsutsugamushi disease

A mite-borne infectious disease caused by a microorganism, Rickettsia tsutsugamushi, characteristically with fever, headache, a raised (macular) rash, swollen glands (lymphadenopathy) and a dark crusted ulcer (called an…
TTP (thrombotic thrombocytopenic purpura)

A life-threatening disease involving embolism and thrombosis (plugging) of the small blood vessels in the brain. TTP is characterized by platelet microthrombi (tiny traveling clots composed of platelets, the clotting…
TTR

The gene that encodes transthyretin, a plasma protein consisting of 127 amino acids that binds retinol and thyroxine. Many distinct forms of amyloidosis have been related to different point mutations in TTR
Tubal occlusion procedure, selective (STOP)

A nonsurgical form of permanent birth control in which a physician inserts a 4-centimeter (1.6 inch) long metal coil into each one of a woman's two fallopian tubes via a scope passed through the cervix into the uterus…
Tubal pregnancy

A pregnancy that is not in the usual place within the uterus but is located in the Fallopian tube. Tubal pregnancies are due to the inability of the fertilized egg to make its way through the Fallopian tube into the…
Tube

A long hollow cylinder. There are many tube-like structures in the human body, such as the auditory tube (Eustachian tube) in the ear
Tube feeding

See: Enteral nutrition
Tube, auditory

The tube that runs from the middle ear to the pharynx, also known as the Eustachian tube. The function of this tube is to protect, aerate and drain the middle ear (and mastoid). Occlusion of the Eustachian tube leads to…
Tube, ear

A small plastic tube inserted into the eardrum to keep the middle ear aerated for a prolonged period of time. These ventilating tubes usually remain in place for 6 months to several years. Eventually, they move out of…
Tube, endotracheal

A flexible plastic tube that is put in the mouth and then inserted down into the trachea (the airway). The doctor inserts the tube with the help of a laryngoscope. The procedure is called endotracheal intubation. The…
Tube, Eustachian

The tube that runs from the middle ear to the pharynx. The function of the Eustachian tube is to protect, aerate and drain the middle ear (and mastoid). Occlusion of the Eustachian tube leads to the development of…
Tube, Fallopian

The two Fallopian tubes, one on each side, transport the egg from the ovary to the uterus (the womb). The Fallopian tubes have small hair-like projections called cilia on the cells of the lining. These tubal cilia are…
Tube, nasogastric

See: Nasogastric tube
Tube, NG

An NG (nasogastric) tube is one that is passed through the nose (via the nasopharynx and esophagus) down into the stomach. An NG tube is a flexible tube made of rubber or plastic and has bidirectional potential. A…
Tube, otopharyngeal

The tube that runs from the middle ear to the pharynx, known also as the Eustachian tube. The function of this tube is to protect, aerate and drain the middle ear (and mastoid). Occlusion of the Eustachian tube leads to…
Tube, swallowing

See: Swallowing tube
Tube, tympanostomy

A small plastic tube inserted into the eardrum to keep the middle ear aerated for a prolonged period of time. These ventilating tubes usually remain in place for 6 months to several years. Eventually, they move out of…