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.

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 […]

‘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.

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 […]

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 […]

A drug that is structurally very similar to already known drugs, with only minor differences. The term “me-too” carries a negative connotation. However, me-too products may create competition and drive prices down.

Coinsurance: A provision by which the insured individual shares in the cost of certain expenses. The same as co-payment.

A temporary local change in the skin when it becomes rougher due to erection of little muscles, as from cold, fear, or excitement. The chain of events leading to this skin change starts with a stimulus such as cold or fear. That stimulus causes a nerve discharge from the sympathetic nervous system, a portion of […]

A pregnant woman who develops a UTI should be treated promptly to avoid premature delivery of her baby and other risks such as high blood pressure. Some antibiotics are not safe to take during pregnancy. In selecting the best treatment, doctors consider various factors such as the drug’s effectiveness, the stage of pregnancy, the mother’s […]

Narrowing of the major artery to the kidney that can lead to seriously elevated blood pressure. Common causes of renal artery stenosis include atherosclerosis and thickening of the muscular wall (fibromuscular dysplasia) of the renal artery.