中文摘要：

稀土化合物的生物效应研究已引起人们的大量关注,但纳米稀土氧化物对细胞产生的生物效应报道较少。为了研究纳米稀土氧化物和稀土离子对正常细胞作用后的影响差异,采用MTT比色实验,形态观察和流式细胞术等方法探讨了纳米Eu2O3和Eu3＋对体外培养的人肝细胞HL-7702生长的影响。结果发现,较低浓度的纳米Eu2O3对细胞生长没有明显影响,较高浓度（≥800μg.ml-1）的纳米Eu2O3作用肝细胞后,具有明显的毒性作用,出现了凋亡特征;而Eu3＋在较低含量,即≤100μmo.lL-1时诱导肝细胞S期细胞比率上升,对肝细胞增殖有较弱的促进作用。

英文摘要：

The biological effects of rare earth element aroused an extensive interest during the past few years.However,the biological effects of rare earth oxide nanoparticles on cells were rarely reported.In the present study,we reported the impact of nano Eu2O3 and Eu3＋ on the HL-7702 cells（a kind of human hepatocyte） using MTT,morphological observation and flow cytometry.The results suggested that the nano Eu2O3 at low concentrations did not make a great impact on cell proliferation whereas it could trigger apoptosis at high concentrations（≥800 μg·ml-1）.On the contrary,Eu3＋ at low concentrations（≤100 μmol·L-1） could slightly promote the proliferation of HL-7702 cells by increasing the ratio of S-phase cells.