HIV infection and related risk behaviours in a disadvantaged youth institution of São Paulo - Brazil - Burattini, Marcelo Nascimento; Massad, Eduardo; Zanetta, Dirce Maria Trevisan; Strazza, Leila; Azevedo, R. S.; Carvalho, Heraclito Barbosa de; Menezes, R. X.; Ferreira, D. P. (International AIDS Conference, XIII, 2000)