Researchers comparing Northern and Southern birds have confirmed a prediction about parents protecting themselves at their offsprings' expense. (p. 271)

A sperm protein for movement also prompts egg maturation and ovulation. (p. 271)

An abnormal protein associated with Huntington's disease kills cells by stealing another protein needed for cell survival. (p. 271)

Injecting radioactive antibodies directly into the cavity left after a brain tumor is surgically removed lengthened patients' lives by as much as 40 weeks in a recent study. (p. 253)

Agents that bind to knots in the normally linear DNA sequence seem to prevent the expression of cancer-causing genes. (p. 253)

Selenium's anticancer benefits may depend on ingestion of the mineral in food, not as a purified dietary supplement. (p. 248)

Inflammatory bowel disease may initially be triggered by chemical reactions that deplete affected tissues of a key antioxidant. (p. 248)

Realizing that many cancers depend on antioxidants for their survival, researchers have successfully designed a dietary strategy that suppresses breast cancer growth and spread, at least in animals. (p. 248)

Breathing in smoke from another person's cigarette causes blood changes that reduce the likelihood that an individual will survive a heart attack. (p. 248)

Scientists are making progress toward inserting genes to cure impotence temporarily. (p. 237)