摘要目的　探讨氟骨症病变骨自由 基变化规律。方法　采用电子自旋共振（ESR）方法观察了不同钙营养 条件下氟中毒大鼠骨自由基含量的变化。结果　低钙偏食组，低钙偏食加氟组骨自由基含量均高于 正常对照组，P<0.01。常规饲料（富钙）单纯加氟组则较对照组偏低，P<0.05。结论　短期少剂量氟在富钙条件下并不引起自由基含量升高，而低钙加氟时自由基含量明显升高，说明自由基变化并非单纯过量氟引起。

abstractsObjective　Recently,it was reported the analy sis of bone free radical by using electron spin resonance (ESR),so this article aimed to determine the changes of bone free radical in fluoresis rats.Methods　To analyze the free radical level of bone in fluoresis rats fed with different dose of calcium by ESR method.Results　The free radical of bone in the group of low ca lcium level and the group low calcium+fluorides was higher than that in the cont rol group (P<0.01),but that in normal animal feeds (calcium-rich)+fluoride group was lower than that in the control group.Conclusions　Low doses of fluoride did not resulted in the increase of free radical in calcium-rich condition at short time,but at low calcium condition,fluoride could increase the level of free radical,these suggested that simple overdose of fluoride did not change the level of free radical of bone.