1. Department of Pulmonary and Critical Care Medicine (PCCM), The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, China
2. Department of Gastroenterology, Fujian Provincial Hospital, Fuzhou, China
3. Department of Gastroenterology, Shengli Clinical Medical College of Fujian Medical University, Fuzhou, China
4. Department of Gastroenterology, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, China
5. Department of Gastroenterology, Dongguan Tungwah Hospital, DongGuan, China