The efficacy of UDCA in treating the parenteral nutrition-associated cholestasis(PNAC) has been identified by some studies in children without short bowel syndrome(SBS).Most of the adults who suffering PNAC have SBS. it limits the potential function of UDCA because of the lack of SBS patients and malabsorption of UDCA.Therefore, we design this clinical trial in our center of SBS to approach the preventative and therapeutical effect of UDCA to PNAC in adults with short bowel syndrome.