- 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.
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.
- 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 […]
- Oral contraceptive, combined
Commonly called “the pill,” combined oral contraceptives are the most commonly used form of reversible birth control in the United States. This form of birth control suppresses ovulation (the monthly release of an egg from the ovaries) by the combined actions of the hormones estrogen and progestin. If a woman remembers to take the pill […]
- Lobotomy: MedTerms by MedicineNet.com
A gene in two or more species that has evolved from a common ancestor. Also called an orthologous gene.
- Non-small cell lung cancer
Cancer of the lung which is not of the small cell carcinoma (oat cell carcinoma) type. The term “non-small cell lung cancer” applies to the various types of bronchogenic carcinomas (those arising from the lining of the bronchi) which include adenocarcinoma, squamous cell carcinoma, and large cell undifferentiated carcinoma. The distinctions between small and non-small […]
- Industrial health
A branch of public health concerned with the health and well-being of workers. Its aims are to eliminate hazards and reduce industrial fatigue in the workplace.