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Callery EM, Elinson RP.Callery EM, et al.Proc Natl Acad Sci U S A. 2000 Mar 14;97(6):2615-20. doi: 10.1073/pnas.050501097.Proc Natl Acad Sci U S A. 2000.PMID: 10706622Free PMC article.