Dang, Xiliang
Lian, Liping
Wu, Dongsheng
Article History
Received: 27 May 2018
Accepted: 15 October 2018
First Online: 27 November 2018
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of Wei Nan Central Hospital. The research was conducted in accordance with the 1964 Helsinki Declaration.
: Signed written informed consent was obtained from the participants and/or their guardians.
: The authors declare that they have no competing interests.
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