Mo, P
Zhou, Q
Guan, L
Wang, Y
Wang, W
Miao, M
Tong, Z
Li, M
Majaz, S
Liu, Y
Su, G
Xu, J
Yu, C
Article History
Received: 8 April 2014
Revised: 1 August 2014
Accepted: 25 August 2014
First Online: 29 September 2014
Competing interests
: The authors declare no conflict of interest.