pubmed-article:17429576 | pubmed:affiliation | Discipline of Pediatric Oncology, Department of Pediatrics, Faculty of Medicine of Ribeirão Preto, University of São Paulo, 3900. Bairro Monte Alegre, Ribeirão Preto, SP CEP 14048-900, Brazil. etvalera@hcrp.fmrp.usp.br | lld:pubmed |