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Glossary

Showing 761-770 out of 1196 Terms

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  • Medicine

    (MEH-dih-sin)

    A substance used in treating disease.

  • Medulloblastoma

    (MED-yoo-loh-blas-TOH-muh)

    A malignant brain tumor that begins in the lower part of the brain and that can spread to the spine or to other parts of the body. Medulloblastomas are a type of primitive neuroectodermal tumor (PNET).

  • Melanocytes

    (meh-LAN-oh-sites)

    A cell in the skin and eyes that produces and contains the pigment called melanin.

  • Melanoma

    MEH-luh-NOH-muh

    A cancerous (malignant) tumor that begins in the cells that produce the skin coloring (melanocytes). Melanoma is almost always curable in its early stages. However, it is likely to spread, and once it has spread to other parts of the body the chances for a cure are much less.

  • Melatonin

    (MEH-luh-TOH-nin)

    A hormone made by the pineal gland (tiny organ near the center of the brain). Melatonin helps control the body’s sleep cycle, and is an antioxidant. It is also made in the laboratory and sold as a supplement.

  • Meningeal leukemia

    (meh-NIN-jee-ul loo-KEE-mee-uh)

    A serious problem that may occur in leukemia. In meningeal leukemia, cancer cells have spread from the original (primary) tumor to the meninges (thin layers of tissue that cover and protect the brain and spinal cord). The cancer may cause the meninges to be inflamed. Also called leukemic leptomeningitis and leukemic meningitis.

  • Meninges

    (meh-NIN-jeez)

    The three thin layers of tissue that cover and protect the brain and spinal cord.

  • Meningitis

    (MEH-nin-JY-tis)

    An infection of the membranes and fluid around the brain and spinal cord.

  • Menopause

    (MEH-nuh-pawz)

    The time of life when a woman’s ovaries stop producing hormones and menstrual periods stop. Natural menopause usually occurs around age 50. A woman is said to be in menopause when she hasn’t had a period for 12 months in a row. Symptoms of menopause include hot flashes, mood swings, night sweats, vaginal dryness, trouble concentrating, and infertility.

  • Menstrual periods

    (MEN-stroo-ul PEER-ee-uds)

    The periodic discharge of blood and tissue from the uterus. From puberty until menopause, menstruation occurs about every 28 days, but does not occur during pregnancy.