Funding for this research was provided by:
National Nature Science Foundation of China (NSFC81370437)
Received: 25 September 2018
Accepted: 3 May 2019
First Online: 14 May 2019
Ethics approval and consent to participate
: This study was approved by the Regional Ethics Committee of Beijing Anzhen hospital, Capital Medicine University in agreement with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. All patients participating to this study signed informed consents.
: Not applicable.
: The authors declare that they have no competing interests.
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