Why does PubMed return more results than Anatomy Lens for MeSH queries?
There are two reasons for this. First, by default, PubMed includes a search by concept-based headings as well as a keyword-based search. As pointed out earlier, a keyword-based search will produce more results because an article might match a subset of words that define a concept (such as tube in respiratory tube development). Second, even if one restricts PubMed search to MeSH terms, PubMed may produce more results because its databases are more up-to-date (Anatomy Lens has the 2008 Medline distribution).
