The compressed trachealcartilage disappeared in 2 cases, became thin and soft in other 34 cases.
局部受压处气管软骨环消失2例，气管软骨环变细、变薄、变软34例。
2
The trachealcartilage stress relaxation curve is changed by the logarithm relations, the trachealcartilage is the non-linear viscoelastic material.
气管软骨应力松弛曲线是以对数关系变化的，气管软骨为非线性粘弹性材料。
3
The formation of saber sheath trachea is caused by the injury of the trachealcartilage due to chronic coughing, resulting in remodeling and dystrophic ossification of the cartilage.