Inefficacy of Piracetam in the Prevention of Painful Crises in Children and Adolescents with Sickle Cell Disease. - Alvim, R. C.; Viana, M. B.; Pires, M. A. S.; Franklin, H. M. O. H.; Paula, M. J.; Brito, A. C.; Oliveira, T. F.; Rezende, P. V. (Acta Haematologica, 2005)