中文摘要：

目的在体外循环条件下，评价脂质体造影剂微泡对超声溶栓的影响及其与超声波频率、强度之间的关系。方法以健康成人静脉全血37℃恒温水浴孵育2h制备体外血栓80份。40份样本被分为单纯超声组、单纯微泡组、微泡＋超声组和对照组。辐照超声为2MHz-1．8W／cm^2、占空比95％的脉冲式超声波，脂质体微泡用量为50μl，各组处理时间为10min。比较各组溶栓率。其余血栓样本分为4组，加入50μl微泡后分别给予2MHz-0．7W／cm^2、2、MHz-1．4W／cm^2、1、MHz-0．7W／cm^2和0．5MHz-0．7W／cm^2的脉冲式超声波辐照10min。计算溶栓率与频率、声强之间的相关性。结果微泡＋超声组溶栓率明显高于单纯超声组（P〈0．05）、单纯微泡组（P〈0．01）和对照组（P〈0．01）。溶栓率与超声频率呈负相关（r1=1．000，P〈0．01），与声强呈正相关（r=-1．000，P〈0．01）。结论在体外循环条件下，脂质体微泡能显著增强超声波溶栓作用，且其效果与超声频率成反比，与声强成正比。

英文摘要：

Objective To evaluate the effect of lipid contrast microbubbles on sonothrombolysis and its relationship with frequency and intensity of ultrasound in the condition of extracorporeal circulation. Methods Eighty thrombi samples were prepared by incubating the whole venous blood from healthy adults in 37℃ thermostatic waterbath for 2 h. The samples were divided into ultrasound group, microbubbles group, microbubbles＋ultrasound group and the control group. The pulse ultrasound （duty cycle being 95%） of 2 MHz-1.8 W/cm^2 and 50 μl lipid microbubbles were applied. The processing time was 10 min in all the groups. The thrombolysis rates between the groups were compared. The rest samples were divided into 4 groups, which were irradiated with pulse ultrasound of 2 MHz-0. 7 W/cm^2 , 2 MHz-1.4 W/cm^2 , 1 MHz-0. 7 W/cm^2 and 0.5 MHz-0.7 W/cm^2 for 10 min after 50 μl microbubbles were added, respectively. The relationship between the thrombolysis rate and the frequency or the intensity of ultrasound was calculated. Results The thrombolysis rate in microbubbles＋ultrasound group was higher than those in ultrasound group （P〈0.05）, microbubbles group （P〈0. 01） and the control group （P〈0. 01）. And there is a negative correlation between the thrombolysis rate and the ultrasound frequency and a positive correlation between it and the intensity. Conclusion The introduction of lipid microbubbles can enhance the sonothrombolysis markedly and it＇s negatively correlated with the frequency and positively correlated with the intensity of ultrasound.