Clinical Research Directory

Inclusion Criteria: * men or women aged 18-80 years * expected feasible abdominal surgical treatment (partial gastrectomy, colorectal resection) * no preoperative intestinal barrier dysfunction * patients voluntarily participated in this study and signed an informed consent form. Exclusion Criteria: * Patients or their families refused to participate in this study * chronic inflammatory diseases (e.g. inflammatory bowel disease, chronic hepatitis, chronic pancreatitis, chronic peptic ulcer, etc.) * history of antibiotic administration in the last 2 weeks * severe cognitive impairment and other inability to cooperate preoperative neoadjuvant radiotherapy * combined with severe hepatic, renal, and cardiac insufficiency patients.