Medical terms - Letter Y | MedicalVocabulary.org

Y (in chemistry)

The symbol for the element yttrium, an ultrarare metal named after Ytterby in southern Sweden. Yttrium has been used in certain nuclear medicine scans
Y (in genetics)

The Y chromosome, the sex chromosome found in normal males, together with an X chromosome
Y chromatin

A brilliantly fluorescent body seen under the microscope in cells containing a Y chromosome when the cells are stained with the dye quinacrine. Quinacrine lights up the Y chromosome more than other chromosomes.
Y chromosome

The sex chromosome found together with an X chromosome in most normal males. Once thought to be a genetic wasteland, the Y now is known to contain at least 20 genes, some of them unique to the Y including the…
Y chromosome infertility

Male infertility with oligozoospermia (a subnormal number of sperm) or azoospermia (the absence of sperm) caused by deletion or rearrangement of the long arm of the Y chromosome, as demonstrated by chromosome analysis…
Y chromosome sex-determining region

See: Y sex-determining region
Y map

The array of genes on the Y chromosome. Once thought to be a genetic wasteland, the Y now is known to contain at least 20 genes. Some of these genes are unique to the Y including the Y-chromosome sex-determining region…
Y sex-determining region

A region on the Y chromosome that determines the sex of the individual. This region goes by the symbol SRY (sex region Y). SRY is necessary and sufficient for male sex determination. It is the testis-determining factor…
Y-linkage

The presence of a gene on the Y chromosome. Y-linkage is analogous to X-linkage (the presence of a gene on the X chromosome) in that it says a gene is on one of the sex chromosomes. It has often been said that little is…
Y-linked

A gene on the Y chromosome. A Y-linked gene is by necessity passed from father to son, since the Y chromosome can only be transmitted by a man to his male progeny. It has often been said that little is known about…
Y-linked gene

A gene on the Y chromosome. (Y-linkage is analogous to X-linkage (the presence of a gene on the X chromosome) in that it says a gene is on one of the sex chromosomes.) It has often been said that little is known about…
Y-linked inheritance

Inheritance of genes on the Y chromosome. Since only males normally have a Y chromosome, Y-linked genes can only be transmitted from father to son. Y-linked inheritance is also called holandric inheritance. It has often…
Y. pestis

Yersinia pestis, the bacteria that causes the bubonic plague which in the year 541 (as the Black Death) and later in the Middle Ages decimated Europe. The effects of the plague are described in the nursery rhyme 'We all…
YAC

YAC stands for yeast artificial chromosome, a vector (carrier) created and used in the laboratory to clone pieces of DNA. A YAC is constructed from the telomeric, centromeric, and replication origin sequences needed for…
YAG laser surgery

The use of a YAG (yttrium-aluminum-garnet) laser to do surgery. One use for a YAG laser in surgery is to punch a hole in the iris to relieve increased pressure within the eye from acute angle-closure glaucoma. In this…
YAMA

See: Caspase 3
Yard

In length, 3 feet or 36 inches or, metrically, 91.44 centimeters. The yard, along with the foot and inch, are English creations to which the USA has stubbornly clung. The yard was originally a unit of measurement of…
Yawn

Involuntary opening of the mouth, often caused by suggestion. Yawning is characterized by breathing first inward, then outward. Repeated yawning is often a sign of drowsiness. It may also sometimes be a sign of…
Yawning

Involuntary opening of the mouth with respiration, breathing first inward, then outward. Yawning is often caused by the power of suggestion. Repeated yawning may be a sign of drowsiness. It can also sometimes be a sign…
Yaws

Yaws: A common chronic infectious disease that occurs mainly in the warm humid regions of the tropics with characteristic bumps on the skin of the face, hands, feet and genital area. Almost all cases of yaws are in…
Yd.

Abbreviation for a yard as a measure of length. A yard equals 3 feet or 36 inches. The metric equivalents for these measures of length are: > >A yard = 0.9144 meter. >A foot = 30.48 centimeters. >An inch = 2.54…
Yeast

A group of single-celled fungi that reproduce by budding. Most yeast are harmless (some are used in baking and brewing). Yeast is commonly present on normal human skin and in areas of moisture, such as the mouth and…
Yeast artificial chromosome (YAC)

A vector (carrier) created and used in the laboratory to clone pieces of DNA. A YAC is constructed from the telomeric, centromeric, and replication origin sequences needed for replication in yeast cells. (The telomere…
Yeast diaper rash

Rash: Infection in the diaper area caused by a yeast formerly called Monilia and now called Candida. These organisms are part of the germs normally found in various parts of the body and ordinarily do not cause any…
Yeast genome

All of the genetic information contained in yeast (Saccharomyces cerevisiae). The genomes of particular nonhuman organisms such as yeast have been studied for a number of reasons including the need to improve sequencing…
Yeast infection

Yeast infection: Overgrowth of yeast can affect the skin (yeast rash), mouth (thrush), digestive tract, esophagus, vagina (vaginitis), and other parts of the body. Yeast infections occur most frequently in moist areas…
Yeast rash

A slightly raised pink-to-red rash caused by proliferation of yeast, usually in a moist area such as the groin. It is most common in infants, but can also occur on the skin of older children and adults. Treatment is by…
Yeast syndrome

The yeast Candida has been thought to cause a syndrome with a number of nonspecific problems including fatigue, loss of appetite, headache, short-attention span, depression and all manner of intestinal irregularities…
Yeast vaginitis

Yeast vaginitis: Infection of the vagina by a fungus known as Candida, characteristically causing itching, burning, soreness, pain during intercourse and urination, and vaginal discharge. Yeast vaginitis occurs when new…
Yeast vulvitis

A yeast infection of the external genital organs of the female (the vulva). The vulva includes the labia, clitoris, and the entrance (the 'vestibule') to the vagina. Yeast vulvitis commonly goes together with yeast…
Yellow enzyme, Warburg's

A key respiratory enzyme discovered by the German biochemist Otto Heinrich Warburg (1883-1970), a pioneer in research on the respiration of cells and the metabolism of tumors. Warburg's yellow enzyme is a flavoprotein…
Yellow enzymes

A group of respiratory enzymes that catalyze reactions in the body permitting cells to respire, to breath. These biochemical reactions are termed oxidation-reduction reactions. The first yellow enzyme was discovered by…
Yellow fever

An acute systemic (bodywide) illness caused by a virus called a Flavivirus. In severe cases, the viral infection causes a high fever, bleeding into the skin, and necrosis (death) of cells in the kidney and liver. The…
Yellow fever vaccination

A live attenuated (weakened) viral vaccine that is recommended for people traveling to or living in tropical areas in the Americas and Africa where yellow fever occurs. Because it is a live vaccine, it should not be…
Yellow jack

1) The flag displayed from lazarettos, naval hospitals, and vessels in quarantine. 2) Synonym for yellow fever as, for example, in '...Fernando passed a few weeks recovering from a touch of yellow jack.'
Yellow jacket sting

A sting from a yellow jacket (or other large stinging insects such as bees, hornets and wasps) can trigger allergic reactions ranging from local responses of limited duration to catastrophic general reactions which can…
Yerba mate

A stimulant beverage similar to tea, very popular in South America, brewed from the dried leaves and stemlets of a member of the holly family known botanically as Ilex paraguayensis. Despite claims to the contrary…
Yersinia

A group of bacteria that appear rod-like under the microscope and include Yersinia pestis (the cause of the bubonic and pneumonic plague), Yersinia entercolitica (the cause of a disease called yersinosis), and Yersinia…
Yersinia enterocolitica

A bacterium that causes an infectious disease called yersiniosis. Yersinia enterocolitica is a member of the Yersinia family of bacteria. Common symptoms of yersiniosis in children (who most often contract the disease)…
Yersinia pestis

The bacteria that causes the bubonic plague which in the year 541 (as the Black Death) and later in the Middle Ages decimated Europe. The effects of the plague are described in the nursery rhyme 'We all fall down.' Y…
Yersinia pestis genome

See: Plague bacterium genome
Yersiniosis

An infectious disease caused by a bacterium called Yersinia enterocolitica (and, less often, other forms of Yersinia). The infection can cause a variety of symptoms depending on the age of the person infected. Common…
Yoga

A way of life that includes ethical precepts, dietary prescriptions, and physical exercise. Its practitioners believe that their discipline has the capacity to alter mental and bodily responses normally thought to be…
Yogurt

A common dish made of milk curdled and fermented with a culture of Lactobacillus (the milk bacillus). The word was acquired in the 1620s from Turkey. It can be spelled myriad ways including yogurt, yoghurt, yaghourt…
Yolk sac

Not all yolk has to do with birds' eggs. Human embryos have a yolk sac, too. The human yolk sac is a membrane outside the embryo that is connected by a tube (the yolk stalk) though the umbilical opening to the embryo's…
Yolk stalk

A narrow tube present in the early embryo that connects the midgut of the embryo to the yolk sac outside the embryo through the umbilical opening. Later in development, the yolk stalk is usually obliterated, but a…
Youth

The time between childhood and maturity. (Unfortunately, as the songwriter Sammy Cahn noted, 'youth is wasted on the young.'
Youth violence

Violence involving young persons, typically children, adolescents, and young adults between the ages of 10 and 24. The young person can be the victim, the perpetrator, or both. Youth violence includes aggressive…
Yttrium

A rare elemental metal. A radioactive form of yttrium is used in radiation therapy and some types of immunotherapy
Yttrium Y 90 ibritumomab tiuxetan

An anticancer drug that is a combination of the radioisotope yttrium-90 and a monoclonal antibody, a produced substances that can locate and bind to cancer cells. Also called IDEC-Y2B8 monoclonal antibody