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本文研究了羟基铬改性(简称改性)后的牛心包瓣组织的稳定性、力学特性和超微形态以及抗钙化性能。结果发现:(1)改性后组织的热皱缩温度由改性前(以戊二醛改性的材料)的86±0.5℃增到100℃,组织湿度和组织增厚率均减低(P<0.05);(2)单轴拉伸测试,其断裂和屈服强度都增强(P<0.05),断裂伸长率显著增加(P<0.01),而屈服伸长率和初始弹性模量则无显著差异;(3)扫描和透射电镜观察,胶原纤维间交联明显,胶原纤维和纤维束致密、均匀;(4)瓣膜试片植入大鼠皮下21天后,其组织钙含量(μg/mg干重)分别由同时植入对照试片的37.29±9.5和29.30±5.65降至3.17±0.23和2.66±0.69。结果表明,羟基铬可显著提高牛心包瓣组织的整体稳定性,增强其抗退变的能力,同时又有较好的抗钙化作用,故此种改性方法的应用很可能带来生物瓣耐久性的新突破。
In this paper, the stability, mechanical properties and ultrastructure of bovine pericardial flap tissue modified by hydroxy chromium (referred to as modified) and the anti-calcification performance were studied. The results showed that: (1) The thermal shrinkage temperature of the modified tissue increased from 86 ± 0.5 ℃ to 100 ℃ before modification (glutaraldehyde-modified material), and both the tissue moisture and tissue thickening rate decreased (P <0.05). (2) Uniaxial tensile test showed that the fracture and yield strengths were enhanced (P <0.05) and the elongation at break was significantly increased (P <0.01), while the yield elongation and initial modulus of elasticity (3) Scanning and transmission electron microscopy showed that the cross-linking of collagen fibers was obvious, the collagen fibers and fiber bundles were dense and uniform; (4) The tissue calcium content (μg / mg Dry weight) decreased from 37.29 ± 9.5 and 29.30 ± 5.65 for the control specimens implanted at the same time to 3.17 ± 0.23 and 2.66 ± 0.69, respectively. The results show that hydroxy chromium can significantly improve the overall stability of bovine pericardial tissue to enhance its ability to resist degeneration, while better anti-calcification, so the application of this modification is likely to bring about the durability of biological valve New breakthrough.