Nested polymerase chain reaction validated for sensitive detection of bovine leukemia virus in blood samples from brazilian cattle herds: comparison with conventional Elisa and agar gel immunodiffusion methods - Gregory, Lilian; Carneiro, Patrícia dos Santos; Birgel Júnior, Eduardo Harry; Beier, D; Akamatsu, Milena Apetito; Harakava, Ricardo; Lara, Maria do Carmo Custódio de Souza Hunold; Pituco, Edviges Maristela; Oliveira, J. C. F; Ferreira, V. C. A; Ikuno, Alice Akimi (Arquivos do Instituto Biológico, 2004)