Sun, Xun http://orcid.org/0000-0002-0381-9826
Xiao, Ye
Li, Pei-mei
Ma, Xiu-yun
Sun, Xiao-jie
Lv, Wen-shan
Wu, Yi-li
Liu, Peng
Wang, Yan-gang
Article History
Received: 28 April 2018
Accepted: 26 September 2018
First Online: 5 October 2018
Ethics approval and consent to participate
: The study protocol was designed in adherence to the Declaration of Helsinki and was approved by the Ethics Committee of the Qingdao University affiliated hospital (No. 2012017). Written informed consent was obtained from all patients.
: Written informed consent for publication was obtained from all patients.
: The authors declare that they have no competing interests.
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