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Raffioni S, Bradshaw RA.Raffioni S, et al.Proc Natl Acad Sci U S A. 1992 Oct 1;89(19):9121-5. doi: 10.1073/pnas.89.19.9121.Proc Natl Acad Sci U S A. 1992.PMID: 1384043Free PMC article.