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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).
electromagnetic radiation emitted from radioactive substances; they are high-energy x-rays but originate from the nucleus rather than the orbital shell and are not deflected by a magnet.
gam·ma rays(gamă rāz)
Electromagnetic radiation emitted from radioactive substances; they are high-energy x-rays but originate from the nucleus rather than the orbital shell and are not deflected by a magnet.
Short wavelength, high energy electromagnetic radiation emitted by radioactive substances.
Mentioned in: Radiation Therapy
gam·ma rays(gamă rāz)
Electromagnetic radiation emitted from radioactive substances; high-energy x-rays that originate from the nucleus rather than the orbital shell and are not deflected by a magnet.