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Morris AP, Chambers CD, Mattingley JB.Morris AP, et al. Among authors: chambers cd.Proc Natl Acad Sci U S A. 2007 May 22;104(21):9069-74. doi: 10.1073/pnas.0610508104. Epub 2007 May 11.Proc Natl Acad Sci U S A. 2007.PMID: 17496146Free PMC article.