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Keri RA, Lozada KL, Abdul-Karim FW, Nadeau JH, Nilson JH.Keri RA, et al. Among authors: nilson jh.Proc Natl Acad Sci U S A. 2000 Jan 4;97(1):383-7. doi: 10.1073/pnas.97.1.383.Proc Natl Acad Sci U S A. 2000.PMID: 10618427Free PMC article.