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Fortunato EA, Dell'Aquila ML, Spector DH.Fortunato EA, et al. Among authors: spector dh.Proc Natl Acad Sci U S A. 2000 Jan 18;97(2):853-8. doi: 10.1073/pnas.97.2.853.Proc Natl Acad Sci U S A. 2000.PMID: 10639169Free PMC article.