Clinical and Biomedical Research, Vol 32, Iss 3 (2012) Clinical & Biomedical Research; v. 32, n. 3 (2012): Revista HCPA Clinical and Biomedical Research; v. 32, n. 3 (2012): Revista HCPA Repositório Institucional da UFRGS Universidade Federal do Rio Grande do Sul (UFRGS) instacron:UFRGS Clinical & Biomedical Research; Vol. 32 No. 3 (2012): Revista HCPA Clinical and Biomedical Research; v. 32 n. 3 (2012): Revista HCPA Clinical and Biomedical Research