...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Ultrasound in Medicine and Biology >Effect of shell type on the in vivo backscatter from polymer-encapsulated microbubbles.
【24h】

Effect of shell type on the in vivo backscatter from polymer-encapsulated microbubbles.

机译：壳类型对聚合物包裹的微泡在体内向后散射的影响。

获取原文
获取原文并翻译 | 示例
   

获取外文期刊封面封底 >>

       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

This study compared in vivo enhancement from four different polymer-encapsulated ultrasound (US) contrast agents. The agents were produced with a rigid shell composed of the biodegradable block copolymer poly[d,l-lactide-co-glycolide] (PLGA) with the lactic and glycolic acid ratios 50:50, 75:25, 85:15 and 100:0 (i.e., increasingly hydrophobic shell compositions). Approximately the same bubble diameter (1.2 mum) and concentration (0.4 g/mL) were obtained for each agent. In four rabbits, audio Doppler signals were acquired from a 10 MHz cuff transducer placed around a surgically exposed vessel (contrast dose: 0.0125 to 0.15 mL/kg). In vivo dose responses were calculated off-line (in dB). Nine rabbit kidneys were imaged during contrast administration (0.1 mL/kg) in power Doppler and grey-scale pulse inversion harmonic (PIHI) modes using an HDI 5000 scanner (Philips Medical Systems, Bothell, WA). Time-intensity curves were produced and the time-to-peak, peak intensity, slope, area under the curve (AUC) andtotal duration of enhancement for each agent were compared. All agents produced marked Doppler enhancement with increasing duration from the 50:50 agent (48 +/- 10 s) to the 75:25 agent (166 +/- 46 s), the 85:15 agent (403 +/- 83 s) and with the 100:0 agent (603 +/- 93 s) lasting longest (p < 0.02). No other parameters changed significantly, except the AUC of the 85:15 agent, which was greater than that of the 50:50 agent (190.75 vs. 61.58; p = 0.02). The in vivo dose-response curves were similar for all agents, with mean enhancement up to 20.6 +/- 1.11 dB (p = 0.17). In conclusion, contrast duration increases by an order of magnitude as the lactic acid component in the polymer-encapsulated bubbles increases and the shell, thus, becomes increasingly hydrophobic. (E-mail: ).
机译：这项研究比较了四种不同的聚合物包裹超声（US）造影剂的体内增强作用。用具有刚性壳的试剂制备，该刚性壳由可生物降解的嵌段共聚物聚[d，l-丙交酯-乙交酯乙交酯]（PLGA）组成，乳酸和乙醇酸的比例为50：50、75：25、85：15和100： 0（即，越来越多的疏水性壳组成）。每种试剂的气泡直径（1.2毫米）和浓度（0.4克/毫升）大致相同。在四只兔子中，从放置在外科手术暴露血管周围的10 MHz袖带换能器中获取了音频多普勒信号（对比剂量：0.0125至0.15 mL / kg）。离线计算体内剂量反应（以dB为单位）。使用HDI 5000扫描仪（Philips Medical Systems，Bothell，WA），以功率多普勒和灰度脉冲反转谐波（PIHI）模式在造影剂给药期间（0.1 mL / kg）对九只兔肾脏成像。绘制了时间强度曲线，并比较了每种药剂的峰均时间，峰强度，斜率，曲线下面积（AUC）和增强的总持续时间。从50:50药剂（48 +/- 10 s）到75:25药剂（166 +/- 46 s），85：15药剂（403 +/- 83 s）持续时间增加，所有药剂均产生明显的多普勒增强），并且100：0代理（603 +/- 93 s）持续时间最长（p <0.02）。除了85:15剂的AUC大于50:50剂的AUC（190.75与61.58; p = 0.02）相比，其他参数没有显着变化。所有药物的体内剂量反应曲线均相似，平均增强至20.6 +/- 1.11 dB（p = 0.17）。总之，随着聚合物包封的气泡中乳酸成分的增加，造影剂的持续时间增加了一个数量级，因此外壳变得越来越疏水。 （电子邮件：）。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号