中文摘要：

目的研究壳寡糖（chito—oligosaccharide，cos）和N-乙酰氨基葡糖（N—acetyl—glucosamine，NAG）对体外培养的成骨细胞MC3T3-E1的作用。方法分别将NAG、COS以10，100，500，1000，2000mg／L的浓度加入培养基中，通用MTT法观察它们对体外培养的成骨细胞的作用。结果NAG的5个浓度梯度均能促成骨细胞增生，以1000mg／L的效果最为明显；COS的5个浓度都有较明显的促细胞增生的作用，以500mg／L为最适浓度。结论NAG和COS对体外培养的成骨细胞均有一定程度的促增生作用，其机制有待进一步研究。

英文摘要：

Objective To study the effects of chito-oligosaccharide （COS） and N-acetyl-glucosamine （NAG） on the proliferation of osteoblasts （MC3T3-E1） in vitro. Methods Two samples were added into culture medium with some concentrations of 10, 100, 500, 1 000, 2 000 rag/L, respectively. The MTT method was used to observe their effects on osteoblasts. Results NAG at the concentrations mentioned above could promote the proliferation of osteoblasts and the concentration of 1 000 mg/L showed the strongest effect. The promotion of COS was more obvious and the most effective concentration was 500 mg/L. ConcLusion In some sense, NAG and COS both can promote the proliferation of osteoblasts in vitro, but the mechanism should be further studied.