Esophageal diseases: gastroesophageal reflux, reflux esophagitis, esophageal polyps, esophageal cancer, esophageal stenosis, varicose veins, esophageal achalasia and so on.

Gastroduodenal diseases: acute gastritis, chronic superficial gastritis, chronic atrophic gastritis, Helicobacter pylori infection, bile reflux gastritis, gastric polyp, gastric stromal tumor, portal hypertensive gastropathy, peptic ulcer, gastric cancer, gastrointestinal dysfunction, duodenal cancer, etc.

Small intestine diseases: acute enteritis, small intestine benign tumor, small intestine adenocarcinoma, infectious enteritis, small intestine hemorrhage, intestinal tuberculosis, acute hemorrhagic necrotizing enteritis's disease, Crohn's disease, etc.

Colon diseases: Crohn's disease, bacillary dysentery, ulcerative colitis, diarrhea associated with dysbacteriosis, intestinal tuberculosis, colorectal polyps, functional constipation, melanosis coli, Hirschsprung's disease, intestinal parasitic diseases, irritable bowel syndrome, colorectal cancer, etc.

Liver diseases: viral hepatitis, drug-induced liver disease, fatty liver, alcoholic liver disease, autoimmune liver disease, liver cirrhosis, hepatic encephalopathy, Budd-Chiari syndrome, hepatolenticular degeneration, hepatic parasitic disease, liver abscess, primary liver cancer, etc.

Biliary diseases: cholelithiasis, acute cholecystitis, acute obstructive suppurative cholangitis, congenital intrahepatic biliary dilatation, biliary ascariasis, gallbladder cancer, cholangiocarcinoma, etc.

Pancreatic diseases: acute pancreatitis, pancreatic cyst, chronic pancreatitis and pancreatic cancer.

Peritoneal and mesenteric diseases: acute bacterial peritonitis, tuberculous peritonitis, spontaneous peritonitis, cancerous ascites, mesenteric lymph node tuberculosis, peritoneal metastatic carcinoma, etc.