The Journal of the American Medical Association (JAMA) features original research, reviews, and editorials covering all aspects of the biomedical sciences. It's published by the American Medical Association.
This resource gives you access to online full-text articles, from 1998 to the present, to JAMA and other JAMA Network journals from the American Medical Association.
The JAMA website also contains career-related materials for students, residents and fellows, as well as course, guidelines, and patient practice materials for physicians.