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Patil KR, Nielsen J.Patil KR, et al.Proc Natl Acad Sci U S A. 2005 Feb 22;102(8):2685-9. doi: 10.1073/pnas.0406811102. Epub 2005 Feb 14.Proc Natl Acad Sci U S A. 2005.PMID: 15710883Free PMC article.