The First Affiliated Hospital of Jinan University;
Jinan University;
Guangzhou 510632;
Guangdong Province;
China;
Department of Cardiology;
The Affiliated Hospital of Binzhou Medical College;
Binzhou 256600;
Shandong Province;
China;
Department of General Surgery;
The First Affiliated Hospital of Jinan University;
Guangzhou 510632;
Guangdong Province;
China;
Early oral feeding; Gastrointestinal tumor; Safety; Efficacy; Meta-analysis; Systematic review;