• 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 […]

  • Onset

    In medicine, the first appearance of the signs or symptoms of an illness as, for example, the onset of rheumatoid arthritis.

  • Cubitus varus

    Cubitus varus: A deformity of the elbow resulting in a decreased carrying angle (so that, with the arm extended at the side and the palm facing forward, the forearm and hand are held at less than 5 degrees). There is deviation of the forearm toward the midline of the body. Cubitus is the Latin word […]

  • CA

    CA: 1. Short (and slang) for cancer and carcinoma. 2. Abbreviation for cardiac arrest; chronological age; coronary artery.

  • Vaccination, DT

    DT (diphtheria and tetanus) vaccine does not protect from pertussis and is usually reserved for individuals who have had a significant adverse reaction to a DPT shot or who have a personal or family history of a seizure disorder or brain disease

  • Chromosome, Y

    Chromosome, Y: The sex chromosome found in normal males, together with an X chromosome. Once thought to be a genetic wasteland, the Y chromosome is now known to contain at least 20 genes. Some of these genes are unique to the Y chromosome, including the male-determining gene and male fitness genes that are active only […]