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Bachman ES, McClay DR.Bachman ES, et al. Among authors: mcclay dr.Proc Natl Acad Sci U S A. 1996 Jun 25;93(13):6808-13. doi: 10.1073/pnas.93.13.6808.Proc Natl Acad Sci U S A. 1996.PMID: 8692900Free PMC article.