Funding for this research was provided by:
National Natural Science Foundation of China (81502886, 81530087, 81373099)
Natural Science Foundation of Beijing Municipality (Z160002)
Key Projects in the National Science & Technology Pillar Program in the Twelfth Five-year Plan Period of China (2011BAI08B01)
Text and Data Mining valid from 2018-07-11
Received: 19 July 2017
Accepted: 2 July 2018
First Online: 11 July 2018
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of Capital Medical University (NO: 2013SY26), and all procedures were performed in accordance with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. Written informed consent was obtained from all the participating subjects. A subject was excluded if he/she refused to participate.
: Not applicable.
: The authors declare that they have no competing interests.
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