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Zheng TM, Zhu WJ, Puia G, Vicini S, Grayson DR, Costa E, Caruncho HJ.Zheng TM, et al. Among authors: grayson dr.Proc Natl Acad Sci U S A. 1994 Nov 8;91(23):10952-6. doi: 10.1073/pnas.91.23.10952.Proc Natl Acad Sci U S A. 1994.PMID: 7971990Free PMC article.