Liu, Zhiyong
Shi, Qiao
Liu, Jiao
Abdel-Razek, Osama
Xu, Yongan
Cooney, Robert N
Wang, Guirong
Article History
Received: 17 August 2015
Accepted: 6 November 2015
First Online: 4 December 2015
Competing interests
: The authors declare no competing financial interests.