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Estève PO, Chin HG, Pradhan S.Estève PO, et al.Proc Natl Acad Sci U S A. 2005 Jan 25;102(4):1000-5. doi: 10.1073/pnas.0407729102. Epub 2005 Jan 18.Proc Natl Acad Sci U S A. 2005.PMID: 15657147Free PMC article.