中文摘要：

目的探讨不同浓度的超声微泡造影剂，在不同声强的超声辐照下，介导DNA质粒转染视网膜母细胞瘤（RB）细胞的效率及可行性，为实现外源基因高效、定向的转移奠定基础。方法将培养的RB细胞分别予以超声条件为0．25，0．5，0．75，1．0，1．25W／cm^2，60S的连续波辐照，微泡造影剂浓度为1％，100．4，20％，30％，以筛选出对RB细胞活性无明显抑制的最适超声声强、辐照时间和微泡浓度。根据以上筛选条件，转染EGFP基因入RB细胞，24～48h后，在荧光显微镜下观察EGFP表达情况，并用RT-PCR对EGFPmRNA进行半定量检测。结果声强〈0．75W／cm^2（60s），以及微泡浓度〈20％时，对RB细胞的活性无明显抑制。当微泡浓度10％，超声声强为0．5W／cm^2或0．75W／cm^2时，介导的DNA质粒对RB细胞转染具有较高的转染效率，明显高于其他实验组。超声声强为0．5W／cm^2或0．75W／cm^2介导的转染效率，在统计学上差异无显著性意义。结论浓度适当的微泡在优化的声强条件下，能够有效地提高DNA质粒在RB细胞中的转染效率。

英文摘要：

Objective To investigate the efficiency and feasibility of DNA plasmid transfected into retinoblastoma （RB） cells by microbubbles of different dosage and ultrasound with various intensity, and to afford a base for effective and directional gene delivery. Methods In order to prevent the harm to RB cells, the optimum ultrasound intensity and microbubbles dosage were screened. The cultured retinoblastoma cells were exposed to different ultrasound with intensity of 0.25, 0.5, 0.75, 1.0 and 1.25 W/ cm^2 respectively, and the time were all 60 s. The other RB cells were exposed to microbubbles of various dosage of 1%, 10%, 20% and 30% respectively. According to the optimum ultrasound intensity and microbubbles dosage, EGFP gene were transfected into RB cells. After 24 to 48 hours, the EGFP expression in the RB cells were detected by fluorescence microscopy and RT-PCR. Results Ultrasound with the intensity under 0.75 W/cm^2 （60 s）, and microbubbles with the dosage under 20%, did no harm to RB cells. The transfected efficiency of the two groups （0.5 W/cm^2 and 0. 75 W/cm^2） were both higher than other groups. Conclusion The efficiency of DNA vector transfected into RB cells could be increased obviously by optimum ultrasound intensity and microbubbles dosage.