Cao, Jingsong
Chen, Ling
Zhong, Xiaoling
Shen, Yingying
Gao, Yan
Chen, Qian
Zu, Xuyu
Liu, Jianghua
Funding for this research was provided by:
National Natural Science Foundation of China (No.81170807, No.81873651, No.81972487)
Major Scientific Research Projects of Hunan health and family planning commission (A2017011)
Scientific Research Fund of Education Department of Hunan Province (No.16B230)
Article History
Received: 20 July 2019
Accepted: 22 October 2019
First Online: 17 January 2020
Ethics approval and consent to participate
: Not applicable.
: Not applicable.
: The authors declare that they have no competing interests.