NLM has comprehensive online help available at http://www.ncbi.nlm.nih.gov/books/NBK3830/?depth=2
There is an online tutorial at https://www.nlm.nih.gov/bsd/disted/pubmedtutorial/cover.html
NLM has comprehensive online help available at http://www.ncbi.nlm.nih.gov/books/NBK3830/?depth=2
There is an online tutorial at https://www.nlm.nih.gov/bsd/disted/pubmedtutorial/cover.html