激光切割316L医用导管的设计方案及制造工艺分析

目的:基于不同切割方式的导管设计方案,开展激光切割316L医用导管的制造工艺及性能研究。方法:采用间断螺旋切割方式,设计直线螺旋切割和斜线螺旋切割2种方案,确定激光切割机的激光参数、切割速度及焦点位置,以氧气作为辅助气体,后处理工艺选用硝酸与氢氟酸作为酸洗液,对加工得到的直线螺旋切割式医用导管和斜线螺旋切割式医用导管与Direxion可扭转微导管进行质量对比,并对其进行可跟踪性、扭控性和抗拉强度测试。结果:激光切割316L医用导管表面相较于Direxion可扭转微导管更加光亮,且切槽边缘更圆润,不易损伤血管。但Direxion可扭转微导管的切槽更密集,切槽宽度更均匀,切槽末端的半圆更加规则。而直线螺旋切割式医用导管相较于斜线螺旋切割式医用导管可跟踪性高50%、扭控性高22%、抗拉强度低33%。结论:激光切割参数及后处理工艺是影响激光切割医用导管外观、尺寸的主要因素,也是提高产品加工、装配合格率的重要保障。同时不同的导管切割设计方式也是影响医用导管物理性能的关键要素。

Safety and efficacy of first-line bevacizumab combined with taxane therapy in Chinese patients with HER2-negative locally recurrent or metastatic breast cancer： findings from the ATHENA study

Background Three randomised trials have demonstrated that combining bevacizumab with first-line chemotherapy significantly improves progression-free survival versus chemotherapy alone in HER2-negative locally recurrent/metastatic breast cancer （LR/mBC）. However, data from Chinese populations are limited and possible differences between ethnic and geographic populations are unknown. This study was conducted to determine whether there are differences in safety and efficacy in patients with HER2-negative LR/mRC between Chinese and Western populations after they receive first-line bevacizumab combined with taxane-based therapy.