1. Department of Nephrology, Qilu Hospital of Shandong University, Jinan, Shandong 250012, P.R. China
2. Department of Medical Administration, Weifang Traditional Chinese Medicine Hospital, Weifang, Shandong 261041, P.R. China
3. Department of Pathology, Qilu Hospital of Shandong University, Jinan, Shandong 250012, P.R. China