1. Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki 852-8102, Japan
2. Department of Hematology, Nagasaki University Hospital, Nagasaki 852-8102, Japan
3. Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8102, Japan
4. Department of Nursing, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8102, Japan