【作者】 张群霞；

【导师】 王志刚；

【作者基本信息】 重庆医科大学 ， 影像医学与核医学， 2005， 硕士

【摘要】 第一节 白蛋白超声微泡造影剂的制备及显影 目的:探索白蛋白超声微泡造影剂制备的最佳条件,并对其增强兔肾显影的有效性和安全性进行验证。 方法:采用正交设计安排实验,分别采用不同的白蛋白与葡萄糖体积比(1:3, 1:4),不同声振时间(80s, 120s)、不同声振功率(7 档, 9 档)进行微泡制备,测定所得微泡的浓度和直径,探讨微泡制备的最佳条件。将在最佳条件下所制备的微泡经静脉注射(0.05ml/kg),观察其对兔肾二维灰阶、彩色多普勒、能量多普勒显像的增强效果。 结果:不同溶液、声振时间和声振功率条件下所得微泡的浓度和直径均不相同。在溶液体积比为 1:4、声振时间为 80s、输出功率为 9档的条件设置下所制备的微泡较理想。体内实验显示:此造影剂可显著增强兔肾二维灰阶、彩色多普勒和能量多普勒显像。 结论:所制备的白蛋白微泡造影剂浓度、直径均可满足超声微泡造影剂的要求,并可显著增强兔肾二维、彩色多普勒、能量多普勒显像,是一种较理想的超声微泡造影剂。 超声造影剂; 白蛋白; 微泡; 肾 超声; 微泡; 质粒; 骨骼肌超声; 微泡; β-半乳糖苷酶更多还原

【Abstract】 PartⅠ PREPARATION OF ALBUMIN ULTRASOUND CONTRAST AGENT AND ENHANCEMENT OF ULTRASOUND IMAGING ON RABBIT KIDNEY Objective: To develop the technique of preparation of albumin ultrasound contrast agent, and to investigate the efficiency and safety of this contrast agent for rabbit kidney imaging. Methods : Effects of different solutions, sonication time and ultrasound intensity on microbubbles were evaluated by orthogonal method. The concentration and diameter of the microbubbles were measured. Before and after intravenous injection of the microbubbles(0.05 ml/kg), The kidneys of ten rabbits were imaged with two-dimensional grey scale, color Doppler and power Doppler imaging system. Results: Concentration and diameter of microbubbles were significantly different among different intensities, time and solutions. 5% albumin mixed with 5% dextrose (1:4), and 80s of sonication time(Sonicator XL2020,output grade 9) were the ideal condition for preparation of the contrast agent. In vivo experiment showed that grey ultrasound contrast agent; albumin; microbubble;kidney ultrasound; microbubble;plasmid; skeletal muscleultrasound; microbubble; β-galactosidaseMethods:Thirty rabbits with left femoral artery ligation were randomly divided into 3 groups: the plasmid pcDNA3.1/VEGF165 local intramuscular injection group(group A), plasmid and microbubble mixture local intramuscular injection plus 1MHz, 2.0W/cm2 ultrasound local irradiation group(group B), and the control group (group C). Changes of blood flow in the internal iliac artery (IIA) and changes of Doppler power of the skeletal muscles after contrast were measured by ultrasonography 1 and 28 days later. In order to evaluate the collateral circulation and angiogenesis in treated regions, Digital subtraction angiography(DSA), immunohistochemical staining of VEGF and factor Ⅷ were performed and microvascular density(MVD) was counted 28 days later. Results:One day later, no significant difference in the blood flow of the internal iliac artery (P>0.05) and power Doppler imaging among the groups was observed,while twenty-eight days later, there was significant difference in the blood flow of the internal iliac artery (P<0.05) and power Doppler imaging between groups. DSA showed that collateral circulation in group B was more than that in group A and C. Immunohistochemical staining showed that the expression of VEGFand factor Ⅷ in group B was higher than that in group A and C. The MVD was significant different between groups(P<0.05). It was the highest in ultrasound-mediated microbubble destruction group. Conclusion: Microbubble-mediated VEGF165 plasmid therapy could promote new vessels growth and collateral circulation development in ischemic skeletal muscles. This provides a new method for the treatment of limb ischemia diseases.更多还原