• Z chromosome

    A sex chromosome in certain animals, such as chickens, turkeys, and moths. In humans, males are XY and females XX, but in animals with a Z chromosome, males are ZZ and females are WZ.

  • ZAP-70

    Zeta-chain-associated protein kinase 70. A member of the protein tyrosine kinase family, ZAP-70 is normally expressed in T cells and natural killer cells and has a critical role in the initiation of T-cell signaling. ZAP-70 is expressed in T cells and tumors of T-cell lineage. A high level of ZAP-70 expression appears restricted to T-cell […]

  • Zebra

    ‘When you hear hoof beats, think of horses, not zebras.’ For example, when someone develops a mild transient cough, a virus infection is the most logical and likely cause, and tuberculosis is a zebra.

  • Zygotic lethal gene

    A gene that is lethal (fatal) for the zygote, the cell formed by the union of a sperm (male sex cell) and an ovum (female sex cell). The zygote would normally develop into an embryo, as instructed by the genetic material within the unified cell. However, a zygotic lethal gene scotches prenatal development at its […]

  • Zygote intrafallopian transfer (ZIFT)

    A technique in which a woman’s egg is fertilized outside the body, then implanted in one of her fallopian tubes. This technique is one of the methods used to overcome infertility, the inability of couples to produce offspring on their own. First, the egg and the male sperm needed to fertilize it are harvested. Then […]

  • Diffuse idiopathic skeletal hyperostosis

    A form of degenerative arthritis characteristically associated with flowing calcification along the sides of the vertebrae of the spine. Abbreviated DISH. DISH commonly includes inflammation (tendonitis) and calcification of the tendons at their points of attachment to bone. Anti-inflammatory medications (NSAIDs), such as ibuprofen, can be helpful in relieving both pain and inflammation. Also called […]

  • White subungual onychomycosis, proximal

    The rarest form of fungus infection of the finger or toenail. (Fungus infection of the finger or toenail is also called onychomycosis.) The infection begins in the nail fold (the portion of the nail opposite the tip of the finger). Proximal white subungual onychomycosis is typically associated with HIV infection (AIDS), though it can follow […]

  • Incubator

    In biotechnology. an apparatus in which environmental conditions can be set and controlled. Incubators are used in microbiology for culturing (growing) bacteria and other microorganisms. Incubators in tissue culture rooms are used for culturing stem cells, lymphocytes, skin fibroblasts and other types of cells. And in the hospital nursery and newborn intensive care unit (NICU), […]

  • Amathophobia

    Amathophobia: An abnormal and persistent fear of dust. Sufferers experience anxiety even though they realize dust poses no threat. From the Greek “amathos” (sand) and “phobos” (fear).

  • Transudate

    A fluid that passes through a membrane, which filters out all the cells and much of the protein, yielding a watery solution. A transudate is a filtrate of blood. It is due to increased pressure in the veins and capillaries that forces fluid through the vessel walls or to a low level of protein in […]