PubMed This link opens in a new windowComprises over 27 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations and abstracts include the fields of biomedicine and health, covering portions of the life sciences, behavioral sciences, chemical sciences, and bioengineering. Provides access to additional relevant web sites and links to the other NCBI (National Center for Biotechnology Information) molecular biology resources.