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Abramova NA, Russell J, Botchan M, Li R.Abramova NA, et al.Proc Natl Acad Sci U S A. 1997 Jul 8;94(14):7186-91. doi: 10.1073/pnas.94.14.7186.Proc Natl Acad Sci U S A. 1997.PMID: 9207066Free PMC article.