2236-3459 2236-3459 S2236-34592013000100231 10.1590/S2236-34592013000100013 Brazil 00 04 2013 00 04 2013 17 39 231 253 4 8 8 79-109 17 3 3 2-33 14 32 32 267-76 5 9 9 59-76 85 85 25-47 25 86 86 75-101 2 132-49 52 74-87