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Oliveira AF, Ruas LP, Cardoso SA, Soares SG, Roque-Barreira MC.Oliveira AF, et al.PLoS One. 2010 Jan 13;5(1):e8644. doi: 10.1371/journal.pone.0008644.PLoS One. 2010.PMID: 20072623Free PMC article.