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Lafferty KD, Dobson AP, Kuris AM.Lafferty KD, et al.Proc Natl Acad Sci U S A. 2006 Jul 25;103(30):11211-6. doi: 10.1073/pnas.0604755103. Epub 2006 Jul 14.Proc Natl Acad Sci U S A. 2006.PMID: 16844774Free PMC article.