MEDLINE (Ovid) This link opens in a new windowMEDLINE is an authoritative bibliographic database that indexes medical information on medicine, nursing, dentistry, veterinary medicine, the health care system, pre-clinical sciences, and more. Created by the National Library of Medicine, MEDLINE uses MeSH (Medical Subject Headings) indexing with tree, tree hierarchy, subheadings and explosion capabilities to search citations from over 5,600 biomedical journals.