It is well-known that the immune function declines with aging. Previous works in our laboratory showed that the production of IL-2, IL-3, GM-CSF and NLK decreased in spleen lymphocytes from aged mice, and gene transcription of these factors was inhibited also. In this study, the signal transduction mechanisms about nitric oxide synthase(NOS) in aging were studied. The immunomodulatory effects of Achyranthes bidentata polysaccharides(ABPS) were also studied. Z-893 is a new analogue of bleomycin, which is a n...