A diagnostic test, using a special probe placed within the esophagus, that employs ultrasound waves to make images of the heart chambers, valves and surrounding structures. Transesophageal echocardiography (TEE) has unusually accurate imaging capabilities that permit the identification of previously unidentified anatomic features and surgical results that may necessitate a change in surgical plan or surgical revision before the patient leaves the operating suite. TEE is used to assess the anatomy and blood flow in congenital heart disease. TEE is used during surgery to evaluate the effects on the heart, for example, of the repair of a congenital heart defect. TEE can detect blood clots in the atrium and is therefore useful in guiding cardioversion (to normalize the heart rhythm) in patients with atrial fibrillation who are prone to form such clots.
- Transfer RNA (tRNA)
A class of RNA that has triplet nucleotide sequence complementary to the triplet nucleotide coding sequences of messenger RNA (mRNA). The role of tRNAs is to bond with amino acids and transfer them to the ribosomes, where proteins are assembled according to the genetic code carried by mRNA
to determine the cause of anemia, to examine iron metabolism (for example, in iron deficiency anemia) and to determine the iron-carrying capacity of the blood. Low transferrin can impair hemoglobin production (since to make hemoglobin, you have to have iron) and so lead to anemia. Low transferrin can be due to poor production of transferrin […]
- Transformation, genetic
A process by which the genetic material carried by an individual cell is altered by the incorporation of foreign (exogenous) DNA into its genome.
- Transforming growth factor
(TGF) One of several proteins secreted by transformed cells that can stimulate the growth of normal cells. Transforming growth factor alpha (TGF alpha or TGF-A) binds the epidermal growth factor receptor (EGFR) and stimulates the growth of endothelial cells (cells that line the inside of blood vessels). Transforming growth factor beta (TGF-beta or TGF-B) is […]
- Transforming principle
“Assuming that the sodium desoxyribonucleate and the active principle are one and the same substance, then the transformation described represents a change that is chemically induced and specifically directed by a known chemical compound. If the results of the present study on the chemical nature of the transforming principle are confirmed, then nucleic acids must […]