• 2019-07
  • 2019-08
  • 2019-09
  • 2019-10
  • 2019-11
  • 2020-03
  • 2020-07
  • 2020-08
  • 2021-03
  • br Conflicts of interest br The authors declare


    Conflicts of interest
    The authors declare no competing interests.
    Availability of data and materials
    The data of patients used in this study are available from the corresponding author upon reasonable request.
    Consent for publication
    Not applicable.
    Ethics approval and consent to participate
    This study was approved by the ethics committee of Peking Union Medical College Hospital. All included patients signed an  informed consent form voluntarily.
    The authors thank all patients who participated in this study.
    Appendix A. Supplementary data
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