PubMed comprises more than 25 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text. . Updated daily. Coverage is from the 1940's to present.
Embase - another crucial resource for discovering biomedical evidence within published, peer-reviewed literature, in-press publications and conference abstracts. Full-text indexing of drug, disease and medical device data - supported by Emtree - helps retrieve precise answers to search queries. Coverage is 1974 to present.
A centralized resource covering databases and tools to help in the study of macromolecular structures, conserved domains and protein classification, small molecules and their biological activity, biological pathways, and systems.