gamma(redirected from gamma-aminobutyric acid (GABA))
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gamma, the third letter of the Greek alphabet, often used to indicate the third member of a series, such as the γ chain of hemoglobin. See also terms beginning gamma.
the third letter of the Greek alphabet, γ, used in names of chemical compounds to distinguish one of three or more isomers or to indicate the position of substituting atoms or groups.
gamma chain disease a type of heavy chain disease that resembles a malignant lymphoma, with symptoms of lymphadenopathy, hepatosplenomegaly, and recurrent infections.
1. a class of plasma proteins composed almost entirely of immunoglobulins, the proteins that function as antibodies. Production of gamma globulin may be increased in the body when there is invasion by harmful microorganisms. An abnormal amount in the blood, a condition known as hypergammaglobulinemia, may be indicative of a chronic infection or certain malignant blood diseases. There is also a rare condition, agammaglobulinemia, in which the body is unable to produce gamma globulin; patients suffering from this are extremely susceptible to infection and must be given frequent injections of gamma globulin serum.
2. immune globulin.
gamma rays (γ-rays) electromagnetic emissions from radioactive substances; they are similar to and have the same general properties as x-rays but are produced through the disintegration of certain radioactive elements. They consist of high energy photons, have short wavelengths, and have no mass and no electric charge. Gamma rays are sometimes used in the treatment of deep-seated malignancies (see radiation therapy).
1. Third letter in the Greek alphabet, gamma.
2. In chemistry, denotes the third in a series, the fourth carbon in an aliphatic acid, or position 2 removed from the α position in the benzene ring.
4. Symbol for photon. For terms having this prefix, see the specific term.
1. Third letter of the Greek alphabet, γ.
2. A unit of magnetic field intensity equal to 10-9 T.
γ/γ/ (gamma, the third letter of the Greek alphabet) the heavy chain of IgG; the γ chain of fetal hemoglobin; formerly, microgram.
1. third letter of the Greek alphabet, see also γ-.
2. obsolete equivalent for microgram.
Γ, γ, the third letter of the Greek alphabet. It is a symbol for photon, heavy-chain immunoglobulins, or the third component in a series of certain chemical groups, such as the gamma-chain of hemoglobin.
gamma(1) Microgram; 10-6g.
(2) An obsolete, non-SI (International System) unit of magnetic field strength equal to 0.795/0.775 ampere/m.
gammaγ Symbol for:
1. Heavy chain of immunoglobulin G–IgG.
2. Hemoglobin monomeric chain.
4. The 3rd carbon in an aliphatic organic molecule Genetics A value calculated by the ratio between synonymous DNA mutations, which don't result in a different amino acid being translated from a codon, and nonsynonymous mutations–which result in a different amino acid being encoded Imaging A measure of contrast 1. Film–The slope of the density vs. exposure curve 2. Electronic display terminology–The slope of the brightness distribution curve; a large gamma indicates a steep slope and high contrast.
Abbreviation for activity coefficient;
1. Gamma (q.v.).
1. Third letter in the Greek alphabet.
2. chemistry The third in a series, the fourth carbon in an aliphatic acid, or position 2 removed from the α position in the benzene ring.
3. Symbol for 10-4 gauss.
4. For terms with the prefix γ, see the specific term.
gammaThe third letter of the Greek alphabet. Often used in medicine to denote a particular class.
gamma(y) radiation electromagnetic radiation of shorter wavelength and higher energy than X-RAYS. See ELECTROMAGNETIC SPECTRUM.
n Greek letter represented by γ. See also Greek letters.
Third letter in the Greek alphabet, gamma; photon.
1. the third letter of the Greek alphabet, Γ or γ.
2. used in names of chemical compounds to distinguish one of three or more isomers or to indicate the position of substituting atoms or groups.
3. used in sensitometry to denote the straight line of a characteristic curve. The greater the film contrast the higher the gamma.
gamma benzene hexachloride
gamma delta T lymphocyte
see T lymphocyte.
a class of plasma proteins composed almost entirely of immunoglobulins, the proteins that function as antibodies. Gamma globulins, immunoglobulins, antibodies and antiserum are often used synonomously and interchangeably. See also antibody.
Commercial preparations of gamma globulin are derived from blood serum of several species and are used for prevention, modification and treatment of various infectious diseases. This type of gamma globulin, which is an immune serum, contains a wide range of antibodies, depending on its method of production, and it provides passive immunity for several weeks. In cattle, its most common use is in the newborn orphan which receives no colostrum. In dogs and cats, it has been used in the prophylaxis, and occasionally treatment, of viral infections.
The production of gamma globulin may be increased in the body by the invasion of harmful microorganisms. An abnormal amount of gamma globulin in the blood, a condition known as hypergammaglobulinemia, may be indicative of a chronic infection or certain malignant blood diseases. There is also a rare inherited condition, agammaglobinemia, in which the body is unable to produce gamma globulin. Animals suffering from this condition are extremely susceptible to infection.
gamma glutamyl transferase (GGT)
see gamma glutamyl transferase.
gamma-aminobutyric acid (GABA)
an amino acid that is one of the principal inhibitory neurotransmitters in the central nervous system. GABAA receptors open chloride channels and GABAB receptors are linked to potassium channels. Avermectins act by stimulating the presynaptic release of GABA and enhancing its binding to the postsynaptic receptors