1413-6538 1413-6538 S1413-65382014000400497 /10.1590/S1413-65382014000400003 Brazil Brazil Brazil 00 12 2014 00 12 2014 20 4 497 512

17 59-76 24 3 3 285-97 2646 261-76 18 52 52 101-19 23 2 2 427-46