Astragalus polysaccharide(APS) is an extract of Astragalus membranaceus Var.mongolicus.The effects of APS on bone marrow and spleen progenitor cells in mitomyci
The pathogenicity of 4 Chinese strains of subgroup J avian leukosis viruses (ALV-J), SD9901,SD9902, YZ9901 and YZ9902, was studied. The results showed that only