Colombo score criterion, the average scores in group C~ D were lower than group B (R0. 01) , and group D than group C(/M). 004 in the 7th week and P=0. 002 in the 13th week).

• D组和C组病理总积分均明显低于B组(P<0.；01)；D组低于C组(第7周；P=0