The latest bibliographic citations and author abstracts from more than 5,200 biomedicine and life sciences journals in nearly 40 languages. Every citation is indexed using the National Library of Medicine's Medical Subject Headings (MeSH) controlled vocabulary. MEDLINE is the largest subset of citations in the PubMed database. Searching MEDLINE via Ovid offers better support for complex literature reviews with the adjacency (ADJn) operator to find terms within "n" words of each other.