1. Clinical Medical College of Jining Medical University, Jining Medical University, Jining, Shandong, P.R. China
2. Jining No.1 People's Hospital, Department of Radiology, Jining, Shandong, P.R. China
3. Jining No.1 People's Hospital, Jining Medical University, Jining, Shandong, P.R. China.