1. Department of General Surgery, Affiliated Hospital of Qingdao University, Qingdao, China;
2. Department of Ultrasound, Affiliated Hospital of Qingdao University, Qingdao, China;
3. Department of Nuclear Medicine, Affiliated Hospital of Qingdao University, Qingdao, China;
4. Department of Intensive Care Unit, Affiliated Hospital of Qingdao University, Qingdao, China;
5. Department of Nephrology, Affiliated Hospital of Qingdao University, Qingdao, China;
6. Department of Epidemiology and Health Statistics, Qingdao University Medical College, Qingdao, China