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PubMed Central Hits One Million Article Mark

PubMed Central (PMC), NLM's free digital archive of full-text journal articles, reached the one million-article mark the week of June 18. The millionth article reportedly came from the American Journal of Pathology. Now in its seventh year, PMC is enhanced each week with articles from over 350 important life sciences journals whose publishers have agreed to deposit current issues. All of the content submitted to PMC is converted to a normalized electronic format for long-term storage and display on the web.

Many of the participating publishers have also benefited from the PMC Back Issue Digitization Project, where NLM scans older issues from cover to cover, starting with volume 1, and creates PubMed citations for articles that are not in PubMed. Jointly sponsored by the Wellcome Trust and Joint Information Systems Committee (JISC) in the UK, the NLM scanning project has collected and collated over 5 million pages of material. As of June 2007, these scanned articles accounted for 675,000 of the million articles in PMC.

Because of back issue digitization, several historically important works are now available in their entirety, including: Annals of Surgery from v.1, 1885; Proceedings of the National Academy of Sciences of the U.S.A. from v. 1, 1915; and all of the titles published by the American Society for Microbiology, including the Journal of Bacteriology, from v.1, 1916. This year, scanning was completed for the American Journal of Public Health v. 2 1912, and very soon BMJ will be available back to v. 1, 1857 along with all of the specialty journals published by the British Medical Association. Each of these titles continues to participate in PMC by submitting current content in full-text electronic form for every issue.

NLM is indebted to a wide range of publishers depositing electronically produced content to PMC and to a host of contributors to the back issue scanning project. Worldwide donations from libraries and associations of disposable back issues have assisted NLM with filling in journal volumes not supplied by publishers. While all donations are gratefully received, two institutions deserve special mention: the Marine Biological Laboratory in Woods Hole, MA and Brown University in Providence, RI.

The staff of NLM's National Center for Biotechnology Information is responsible for the technical oversight of PMC and for the flow of current and scanned content, enabling PMC to grow exponentially each month. The staff of Library Operations manages contract activities, quality control and journal issue collection for the scanning project. To learn more about PubMed Central, or to browse its contents, go to: //