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Chen WW, Watkins PA, Osumi T, Hashimoto T, Moser HW.Chen WW, et al. Among authors: watkins pa.Proc Natl Acad Sci U S A. 1987 Mar;84(5):1425-8. doi: 10.1073/pnas.84.5.1425.Proc Natl Acad Sci U S A. 1987.PMID: 3469675Free PMC article.