MEDLINE MEDLINE provides authoritative medical information on medicine, nursing, dentistry, veterinary medicine, the health care system, pre-clinical sciences, and much 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 4,800 current biomedical journals. Included are citations from Index Medicus, International Nursing Index, Index to Dental Literature, HISTLINE, SPACELINE, PREMEDLINE, AIDSLINE, BIOETHICSLINE, and HealthSTAR.