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Silva SM, Rosa VF, Brandão PR, Oliveira AC, Oliveira PG, Sousa JB.Silva SM, et al.Rev Col Bras Cir. 2011 Sep-Oct;38(5):349-54. doi: 10.1590/s0100-69912011000500012.Rev Col Bras Cir. 2011.PMID: 22124648Free article.Portuguese.