a
National Engineering Research Center for Biomaterials, Sichuan University, Chengdu 610064, P. R. China
E-mail: huaai@scu.edu.cn
;
Fax: +86-28-85413991
;
Tel: +86-28-85413991
b
Sichuan Key laboratory of Medical Imaging, North Sichuan Medical College, Nanchong 637007, China
E-mail: zhujiang312@hotmail.com
;
Tel: +86-817-2802315
c
Department of Radiology, West China Hospital, Sichuan University, Chengdu 610041, China
d
Philips Healthcare, Beijing 100020, China