【摘要】 目的　了解温石棉与烟溶液单独及联合作用对细胞DNA损伤后的修复影响。方法将人肺泡上皮细胞用温石棉或烟溶液作用 1h ,即刻去毒培养不同时间后 ,用单细胞凝胶电泳技术测定DNA链断裂情况 ,从而分析DNA的修复功能。结果　 4 0 μg ml温石棉与 2 5× 10 - 4 支 ml烟溶液作用 1h后 ,均可明显引起DNA链断裂 ,温石棉染毒组在继续培养 3h后 ,DNA可出现明显修复 ,4h的修复率达 3 0 6% ;烟溶液染毒组在继续培养 2h后即可出现明显修复 ,4h的修复率达 65 2 % ;二者联合作用后的修复情况与烟溶液单独作用相似。结论　石棉所致的DNA损伤比烟溶液所致的损伤更难修复。更多还原

【Abstract】 Objective Tostudytheeffectofchrysotileandsolutionofcigarettesmokeseparatelyor combinedonDNAdamageandrepair.Methods Single cellsgelelectrophoresisassaywasusedtodetectbreakin DNAstrandandtoanalyzeitsrepairfunctioninhumanalveolarepithelialcelllineA5 4 9,whichwereexposedto chrysotileorcigarettesmokesolutionseparatelyorcombinedforonehourandthenimmediatelyculturedfor differenttime .Results BreakinDNAstrandswasinducedobviouslyinA5 4 9cellsafterexposureto 4 0 μg mlof chrysotileor2 5× 10 - 4 cig mlofcigarettessmokesolutionforonehour.RepairforDNAbreakcouldbeseen clearlyinchrysotile treatedcellsaftercontinuingcultureforthreehours,and 3 0 6%hadbeenrepairedafter cultureforfourhours.Repaircouldalsobeseenclearlyincigarettesmokesolution treatedcellsaftercontinuing culturefortwohours,and 65 2 %hadbeenrepairedaftercultureforfourhours.RepairofDNAincellsexposedto bothchrysotileandcigarettesmokesolutioncombinedwassimilartothatexposedtocigarettesmokesolutiononly. Conclusion DamagetoDNAcausedbychrysotileismoredifficulttorepairthanthatinducedbycigarettesmoking solution .更多还原