SD lymphocyte apoptosis in rat PP knot characteristic DNA ladder bands. 5-7 lanes repressed the control group DNA ladder bands at 2 weeks, 4 weeks and 8 weeks. 3, 4 and 8 lanes repressed the suture group DNA ladder bands at 2 weeks, 4 weeks and 8 weeks. 1, 2 and 9 lanes repressed the model group DNA ladder bands at 2 weeks, 4 weeks and 8 weeks. In the suture group 8 weeks and the model group 8 weeks rat ileal PP knot lymphocyte small molecule DNA showed typical “trapezoid” (200 bp and 400 bp) bands.