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Loyola Filho AI, Uchoa E, Firmo Jde O, Lima-Costa MF.Loyola Filho AI, et al.Cad Saude Publica. 2005 Mar-Apr;21(2):545-53. doi: 10.1590/s0102-311x2005000200021. Epub 2005 Mar 21.Cad Saude Publica. 2005.PMID: 15905917Free article.Portuguese.