1. Department of Internal Medicine, Harbin Medical University Cancer Hospital, Harbin Medical University, Harbin, Heilongjiang 150081, China
2. Department of Intensive Care Medicine, Harbin Medical University Cancer Hospital, Harbin Medical University, Harbin, Heilongjiang 150081, China
3. Heilongjiang Academy of Medical Science, Harbin, Heilongjiang 150081, China
4. Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA