1. Central Laboratory, Affiliated Hospital of Yanbian University, Yanji, Jilin 133002, P.R. China
2. Key Laboratory of Pathobiology, State Ethnic Affairs Commission, Yanbian University, Yanji, Jilin 133000, P.R. China
3. Department of Pathology, Yanbian University Medical College, Yanji, Jilin 133000, P.R. China