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Cohn SM, Roth KA, Birkenmeier EH, Gordon JI.Cohn SM, et al.Proc Natl Acad Sci U S A. 1991 Feb 1;88(3):1034-8. doi: 10.1073/pnas.88.3.1034.Proc Natl Acad Sci U S A. 1991.PMID: 1992454Free PMC article.