Medical database maintained by the NCBI (National Center for Biotechnology In-formation), which is part of the National Library of Medicine (NLM) at the National Institutes of Health (NIH). PubMed indexes almost 5,500 journals with a total of more than 22 million articles in medicine, health, nursing, veterinary medicine, etc. The record goes back to the 1950s. From PubMed, there are links to many full text articles.
PubMed User Guide