Webster's New World Medical Dictionary

transaminase, serum glutamic oxaloacetic
See
aspartate aminotransferase.
transaminase, serum glutamic pyruvic
See
alanine aminotransferase.
transcription
Making an RNA copy from a
sequence of DNA (a gene). Transcription is the first
step in gene expression.
transfer RNA
See 
RNA, transfer.
transferred ophthalmia
See 
sympathetic
ophthalmia.
transfusion
The transfer of blood or blood
products from one person (the donor) into the
bloodstream of another person (the recipient). In
most situations, transfusion is done as a lifesaving
maneuver to replace blood cells or blood products
lost through severe bleeding. Transfusion of one’s
own blood (autologous transfusion) is the safest
method, but it requires advanced planning, and not
all patients are eligible. Directed donor blood
allows the patient to receive blood from known
donors. Volunteer donor blood is usually most
tracheoesophageal puncture
428
21_189283 ch20.qxp 4/18/08 10:19 PM Page 428
http://www.rashidislamiccenter.com
http://www.allofislam.com/

---

readily available and, when properly tested, has a
low incidence of adverse events.
transfusion medicine
The practice of blood
transfusion and blood conservation, complemen-
tary activities that ensure the best balance between
safety and convenience during emergency care or
surgery.
transient ischemic attack
An event that affects
the central nervous system and has the signs and
symptoms of a stroke but that goes away within a
short period of time. Abbreviated TIA. A TIA is due
to a temporary lack of adequate blood and oxygen
(ischemia) to the brain. This is often caused by the
narrowing (or, less often, ulceration) of the carotid
arteries (the major arteries in the neck that supply
blood to the brain). TIAs typically last 2 to 30 min-
utes and can produce problems with vision, dizzi-
ness, weakness, and trouble speaking. If a TIA is not
treated, there is a high risk of a stroke in the near
future, usually within 90 days. A person who even
remotely suspects a TIA should seek medical atten-
tion right away. Medication and/or a procedure to
clean out the carotid artery and restore normal
blood flow through the artery (carotid endarterec-
tomy) can markedly reduce the risk of a subsequent
stroke. Also known as mini-stroke.