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Hyde JS, Mertz JE.Hyde JS, et al.Proc Natl Acad Sci U S A. 2009 Jun 2;106(22):8801-7. doi: 10.1073/pnas.0901265106. Epub 2009 Jun 1.Proc Natl Acad Sci U S A. 2009.PMID: 19487665Free PMC article.