利用图解法绘出剪刃的运行轨迹以及各机构元件使用磨损后对运行轨迹的影响，分析了带钢厂曲柄连杆式飞剪轧件剪切过程中轧件剪切不断......

Retention of urine after parturition isfrequently encountered in obstetricepractice.Many methods of treatment can beadop......