1. Department of Anesthesiology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, P. R. China;
2. Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, P. R. China;
3. Department of Hepatobiliary Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, P. R. China;
4. Key Laboratory of Functional Polymer Materials, Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin, P. R. China