摘要：Before President George W. Bush arrived in the Oval Office, most Americans had never heard of a stem cell - a microscopic biological entity that can transform into hair, muscle or other human cell typ... 阅读全文

摘要：Genes could increase male homosexuality while boosting female reproduction.A survey of Italian men has provided evidence that homosexuality may be partly influenced by genetics. The same genes that ar... 阅读全文