1. Department of Pathology, Cangzhou People's Hospital, Cangzhou, Hebei 061001, P.R. China
2. Department of Pathology, The Third Medical Center of The Chinese People's Liberation Army General Hospital, Beijing 100039, P.R. China
3. Department of Orthopedics, The Hospital of Integrated Traditional and Western Medicine of Cangzhou, Cangzhou, Hebei 061001, P.R. China