生物补片组织方向性对其力学性能的影响

目的力学性能是保证补片临床效果的重要特性。生物补片具有组织排列的方向性(以下简称组织方向性),而这种特性对其力学性能的影响尚未见有详细的研究。本研究拟使用同种异体真皮基质补片和牛心包补片,测试其不同组织方向的力学性能,为相关行业产品的研发、检验、监管以及应用提供参考。方法取同种异体真皮基质补片和牛心包补片各6片,每2片同材质补片为一组,每片样品分别沿平行和垂直于组织方向各裁取3个试样用于同项目测试。使用单立柱电子拉力试验机,分别测量2种补片在平行和垂直于组织方向的拉伸强度、断裂伸长率、缝合强度以及撕裂强度。使用单尾t检验分析不同组织方向测试结果是否具有差异性,并对比不同组织方向的测试现象。结果两种补片的各项力学性能测试结果均表现出了明显的组织方向差异性。平行于组织方向的拉伸强度和断裂伸长率均明显高于垂直于组织方向的测试结果(P<0.05),而缝合强度和撕裂强度均明显低于垂直于组织方向的测试结果(P<0.05)。并且在缝合强度和撕裂强度的测试中,样品的破损情况也表现出了明显的组织方向差异性。结论生物补片的组织方向性会对其力学性能产生影响,建议在产品的性能测试和评估中应加以区分,以便更全面地体现产品性能,促进产业的高质量发展。

Application of the condenser lens in microwave hyperthermia

According to the aplanatism theory, lens can be used to focus the electromagnetic wave. A piano-convex hyperboloid of revo- lution lens made of low loss material is designed for combinatorial applications with the rectangle microstrip applicator in microwave hyperthermia. Results of the extensive simulations and experiments show that the introduction of the lens to the clinical used antenna can significantly improve the directivity and hence increase the microwave power density in near field. In microwave hyperthermia applications, the lens antenna will exhibit superior directivity, high gain and well thermal efficiency for tumor in superficial layer. Besides, it has small treatment area that is helpful for reducing the injury of the normal tissue around the tumor.