helicobacter pylori and ulcers disease

acid anatomical anatomy bacteria bacterial belly biology body bowel cancer care cell colitis cross diagram digestion digestive disease duodenal duodenum education esophagus gaster gastric gastritis gastrointestinal gram gut health healthcare healthy heartburn helicobacter human infection inflammation intestine medical medicine microbiology mucosa mucous negative organ pain parasite peptic problem protective pylori research scheme science section stomach system tissue tract treatment tumor ulcer ulcerative ulcers vector weakens