Received: 6 April 2021
Accepted: 12 August 2021
First Online: 21 August 2021
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standard. This study was approved by the Ethics Committee of Beijing Chest Hospital, Capital Medical University. and the institutional review board approved a waiver of patient informed consent.
: Not applicable.
: The authors declare no competing interests.