• 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 […]

  • Muscular atrophy, post-polio (PPMA)

    Late muscle wasting that occurs as part of the post-polio syndrome (PPS), a constellation of symptoms and signs that appear belatedly, from 20 to 40 years, after the initial polio infection and at least 10 years after what was once thought to be the “recovery” from polio. PPS is no small problem. It is estimated […]

  • Interventional radiology (IR)

    Interventional radiologists employ image guidance methods to gain access to the deep interstices of most organs and organ systems. Through a galaxy of techniques, they can treat certain conditions percutaneously (through the skin) that might otherwise require surgery. (The technology includes the use of balloons, catheters, microcatheters, stents, therapeutic embolization (deliberately clogging up a blood […]

  • Sulfonylurea sensitivity

    Sensitivity to the hypoglycemic effects of the oral hypoglycemic agents in the sulfonylurea class.

  • Reading retardation

    Reading retardation means impaired ability to read. Reading retardation is an impairment that may, for example, reflect mental retardation or cultural deprivation. Reading retardation is different from dyslexia, a specific reading disability due to a defect in the brain’s (higher cortical) processing of graphic symbols; in other words, dyslexia is a learning disability that alters […]

  • Injury

    Harm or hurt. To harm, hurt, or wound. The word injure may be in physical or emotional sense. From the Latin injuria meaning injury.