Paper Chase is a research database designed to offer abstracts of research articles published in journals that have a highly rated impact factor as determined by ISI Impact Factor and PageRank. Abstracts are organized by date, with the most recently published papers listed first. 

Paper Chase

Geographic variation in Medicare services.

N. Engl. J. Med.. Apr 18, 2013;368(16):1465-8.
Newhouse JP, Garber AM.

Department of Health Care Policy, Harvard Medical School, Boston, MA, USA.