Social inequality and vulnerability to the infection for HIV: the Brasilian youths´case - Takahashi, Renata Ferreira; Fracolli, Lislaine Aparecida; Nichiata, Lucia Yasuko Izumi; Campos, Célia Maria Sivalli; Gryschek, Anna Luíza de Fátima Pinho Lins; Ciosak, Suely Itsuko (ICN-Quadrennial Congress, 2001)