小肠黏膜下基质弹性模量的测定

ELASTIC MODULUS OF SMALL INTESTINAL SUBMUCOSA

目的对新型的生物衍生支架材料小肠黏膜下基质(smallintestinalsubmucosa,SIS)的弹性模量进行测定。方法用材料实验机对3只犬的21个SIS样本(每只犬各取7个)进行力学测试。沿管腔纵轴剖开SIS管壁,平行于管腔纵轴拉伸。经预调处理后进行正式拉伸实验,直至组织拉断,拉伸速度为5mm/min,测试温度为常温。结果21个样本测试后得到了应力-应变曲线,采用幂指函数σ=Kεα对应力-应变关系进行拟合,拟合曲线的平均相关系数R2达到0.9916,得到弹性模量表达式E=K1/ασ1-1/α。由实验得到α、K的平均值为3.9669和374.5500,由此得到E=4.3992σ0.75。结论弹性模量随应力增加而增加,变化规律与血管弹性模量变化规律一致。当σ取0.0133MPa(100mmHg)时,SIS的弹性模量约为0.1600MPa,与血管的弹性模量相似。

Objective to determine the modulus of elasticity （E） of small intestinal submucosa （SIS）, a new biological graft material. Methods The longitudinal tensile testing was performed on 21 specimens of canine jejunum with the electronic material test machine. Results Stress （σ）-strain （ε） data were obtained. It was found that the stress （σ）-strain （ε） data fitted the expression σ=Kε^α very well, the mean correlation coefficients Rz was 0. 991 6. Then the expression of the modulus of elasticity （E） of SIS was E=K^1/ασ^1-1/α. The mean values of a and K were 3. 966 9 and 374.55,so E=4. 3992σ^0.75. Conclusion The modulus of elasticity was found to increase with increasing stress. The variations law is similar to that of the vessels. Furthermore when a is 0. 01333 MPa（100 mmHg） ,E is about 0. 16 MPa, which is similar to that of the vessels.