1. Medical School of Chinese PLA No. 28 Fuxing Road Beijing 100853 P. R. China
2. Department of Radiology The First Medical Center Chinese PLA General Hospital Beijing 100853 P. R. China
3. School of Microelectronics Shanghai University Shanghai 201800 P. R. China
4. CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology of China Beijing 100190 P. R. China
5. Department of Medical Imaging Chinese PAP Force Hospital of Beijing Beijing 100600 P. R. China