目的 探讨超声微泡转基因技术介导增强型绿色荧光蛋白（enhanced green fluorescent protein，EGFP）基因在兔骨缺损处转染时，不同超声辐照时间对转染效率及局部组织的影响。 方法 3 月龄雄性新西兰大白兔 30 只，体质量 2.5～3.0 kg，制备右尺骨骨缺损模型，并随机分为 5 组（n=6）。造模后第 10 天于骨缺损断端间注射 EGFP 质粒微泡混悬液（0.3 mL/kg）后，在超声频率 1 MHz、超声强度 0.5 W/cm2、占空比 20% 条件下，对骨缺损部位分别进行 1、2、3、4、5 min 超声辐照（分别为 1、2、3、4、5 min 组）。观察动物存活情况；转染后 1 周取材，大体观察骨缺损处软组织形态；荧光染色观察基因表达情况；HE 染色及透射电镜观察局部组织损伤情况。 结果 各组动物均存活至实验完成。转染后 1 周各组骨缺损处有软组织生长，周围肌肉组织部分内陷填充于其间。荧光显微镜下观察，各组兔骨缺损处均有绿色荧光表达，其中 2 min 组表达最强，1 min 组表达最弱，其吸光度（A）值与其他各组比较差异有统计学意义（P<0.05）；3、4、5 min 组间差异无统计学意义（P>0.05）。HE 染色及透射电镜观察示，各组骨缺损处局部均有不同程度组织损伤，损伤程度随辐照时间的延长而加重。 结论 超声微泡转基因技术介导 EGFP 质粒在兔骨缺损部位转染时，其转染效率和超声辐照时间相关。当超声参数为 1 MHz、0.5 W/cm2、20% 占空比时，超声辐照 2 min 可获得最佳转染效率及相对较轻的组织损伤
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