1. Department of Hematology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
2. Department of Medicine, Yale New Haven Hospital, New Haven, CT, USA
3. Department of Hematology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
4. Department of Intensive Care, Xiangya Hospital, Central South University, Changsha, Hunan, China
5. Department of Intensive Care, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
6. School of Public Health, Yale University, New Haven, CT, USA