摘要
目的为评估超声的溶栓作用和能否增强尿激酶的溶栓作用.方法采用体外实验方法,先制备血栓,置于37℃流动的缓冲液中,超声照射距离为4 cm,脉冲式照射,时间为60、90、120、180 min,观察同一频率(800 kHz)、不同声强(0.2～0.8 W/cm2)的超声和超声加尿激酶(0.17 U/ml,0.34 U/ml)对血栓失重的影响.所测的数据经统计学处理.结果从血栓失重的结果来看,与对照组相比,0.2 W/cm2的超声,180min时的血栓失重,有统计学意义(P＜0.05).随着声强增大,有统计学意义的溶栓时间明显缩短,0.4 W/cm2时为90 min,而0.6 W/cm2和0.8 W/cm2时,60 min即出现非常显著的差异(P＜0.001).超声(800 kHz、0.6 W/cm2)加尿激酶的溶栓结果,60 min时即有非常显著溶栓作用(P＜0.001),血栓重量,从起始的508±5.51 mg减少至180 min的347.66±3.66 mg,减少了161±1.85 mg,而单用尿激酶组只减少99.5±5.02 mg.两组各个时段所测得的血栓失重相比均有明显差异(P＜0.001).结论本组所用的超声对血栓有显著的溶解作用,超声加尿激酶则有增强溶栓作用.
Objective To evaluate whether therapeutic ultrasound, applied alone or with urokinase, may have a thrombolytic effect on blood clots in vitro.Methods Experiments were carried out in a flow model in degassed phosphate buffer at 37℃ at a distance of 4 cm from the ultrasound probe to the blood clots. A same frequence （800 kHz） pulsed wave ultrasound at different intensity levels （0.2 - 0.8 W/cm^2） and exposure time （60, 90, 120, and 180 min） was assessed for its potential to induce weight loss of blood clots used. The ultrasound effect was also studied in combination with urokinase at two concentration, i.e. 0.17 U/ml, 0.34 U/ml. The data obtained were statistically analyzed. Results In terms of weight loss of blood clots using of ultrasound alone showed a significant thrombolytic effect at 0.2 W/cm^2 of intensity and 180 min of exposure time, compared with the control group. Stronger intensity leads to more significant thrombolytic effect. At the intensity of 0.4 W/cm^2, the significant thrombolytic effect occurred at exposure time of 90 min, while at intensity of 0.6 W/cm^2 and 0.8 W/cm^2, it occurred at 60 min. Compared with the control group the statistical difference was significant （P 〈 0.001 ） . When ultrasound was combined with urokinase, the significant thrombolytic effect occurred at 60 min. The clot weight in combined group decreased from initial weight of （ 508 ± 5.51 ）mg to （ 347.66 ± 3.66） mg at 180 min, being a decrease of （ 161 ± 1.85） mg, whereas in urokinase alone group it was （99.5 ± 5.02 ） mg. At different exposure time in the two groups the statistical difference was very significant （ P 〈 0.001 ） . Conclusion The ultrasound used in this experiment has the potential to induce thrombolytic effect and enhance the urokinase - mediated thrombolysis.
