One hundred and twenty-four patients of abdominal operation at selective time were randomized into a routine drug anesthesia group ( group A , 24 cases ) , a meridian point 2 Hz group ( group B , 26 cases ) , a me ridian point 2 Hz/100 Hz group ( group C , 25 cases ) , a meridian point 100 Hz group ( group D , 24 cases ) and a transcutaneous acupoint electric stimulation 2 Hz/100 Hz group ( group E , 25 cases ) .