1. College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
2. State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
3. Division of Echocardiography, Department of Cardiology, Gansu Provincial Hospital, Lanzhou 730000, China