Hu, Jungang
Zhu, Xu
Wang, Xiaodong
Cao, Guang
Wang, Xiao
Yang, Renjie
Funding for this research was provided by:
Beijing Municipal Science & Technology Commission (Z141107002514075)
National Natural Science Foundation of China (81471759)
Article History
Received: 13 November 2018
Accepted: 13 March 2019
First Online: 18 March 2019
Ethics approval and consent to participate
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.For this retrospective study formal consent is not required.
: Not applicable.
: The authors declare that they have no competing interests.
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