A Randomized, Controlled, Open-label Study to Assess the the Efficacy of Enteral Nutrition in Fill of the Treatment Blank Period of the Postoperative Maintain Remission Medication for Crohn's Disease (CD).

Crohn's disease(CD) is a agnogenic disease which has a lifelong relapse tendency even after surgery treatment.So maintain remission medications were routinely given to patients after surgery.But maintain remission medications,as azathioprine,6-MP, ciclosporin,tripterygium glycosides, had a onset time.The therapeutic effect may appear 3 months~6months after taken medicine.There is a treatment blank period between surgery and onset time of maintain remission medications.Enteral nutrition has been used in the induction remission and maintain remission for CD.May be it can fill the treatment blank period.