1. Department of Clinical Laboratory, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
2. The Key Laboratory of Medical Diagnostics in the Ministry of Education and Department of Clinical Biochemistry, College of Laboratory Medicine, Chongqing Medical University, Chongqing, Sichuan 400010, P.R. China
3. Department of Endocrinology, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, Sichuan 400010, P.R. China