‘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.
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 […]
- 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.
- Primary amenorrhea
Absence of menstruation. Amenorrhea is conventionally divided into primary and secondary amenorrhea. With primary amenorrhea, menstruation never takes place. It fails to occur at puberty. With secondary amenorrhea, menstruation starts but then stops. The absence of menstruation during pregnancy is a form of physiologic amenorrhea, physiologic in the sense that it is completely normal and […]
A compound that mimics the biological action of a peptide.