1 Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
2 Department of Medical Research, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
3 Department of Nursing, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
4 Department of Radiation Oncology, National Cheng Kung University Hospital, Tainan 704, Taiwan. Electronic address: p.y.tasi313@gmail.com.