1 | Intensive Care Unit, the Second Xiangya Hospital, Central-South University, Changsha, China |
2 | Department of Respiratory Medicine, The Second Xiangya Hospital, Central-South University, Changsha, China |
3 | Division of Respiratory Disease, Department of Internal Medicine, The Second Xiangya Hospital, Central-South University, Changsha, China |
4 | Department of Respiratory Medicine, Hunan Provincial People’s Hospital, Changsha, China |