Text and Data Mining valid from 2019-01-22
Received: 23 June 2018
Accepted: 6 January 2019
First Online: 22 January 2019
Ethics approval and consent to participate
: The study protocol was approved by the Ethic Committee of the Tianjin First Center Hospital and conducted in accordance with Helsinki’s Declaration. All the patients gave their written information consent.
: Not applicable.
: The authors declare that they have no competing interests.
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