Huang, Qing
Huang, Yongzhi
Luo, Qu
Fan, Wei
Article History
Received: 20 September 2017
Accepted: 10 April 2018
First Online: 17 April 2018
Ethics approval and consent to participate
: The need for informed consent was waived by the Ethics Committee of the West China Hospital of Sichuan University because this was a retrospective study. The study protocol was approved by the Ethics Committee of the West China Hospital of Sichuan University (2016–324). The study was carried out in accordance with the Declaration of Helsinki.
: The authors declare that they have no competing interests.
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