8Raulet DH. Development and tolerance of natural killer cells[J].Current Opinion in Immunology, 1999, 11: 129-134.
9Biron CA, Nguyen KB, Pien GC, et al. Natural killer cells in antiviral defense and function and regulation by innate cytokines[J].Immunity, 1999, 17:189-220.
10Liu Y, Sheng Y, Yuan G, et al. Purification and physicochemical properties of different polysaccharide fractions from the water extract of Boschniakia rossica and their effect on macrophages activation[J]. Int J Biol Macro- mol, 2011, 49(5): 1 007-1 011.
