Han, Yanfu
Sun, Tianjun
Han, Yanqing
Lin, Lingling
Liu, Chang
Liu, Jing
Yan, Guangzhi
Tao, Ran
Funding for this research was provided by:
Beijing Nova Program (No. Z1511000003150128)
Science and Technology Special Fund for Social Development of Hainan (2015SF45)
Hebei Province health and Family Planning Commission Research Fund Project (20181578)
Article History
Received: 12 August 2018
Accepted: 23 January 2019
First Online: 8 February 2019