Gastroscopy: Endoscopic examination, therapy or surgery of the interior of the stomach.Gastroscopes: Endoscopes used for examining the interior of the stomach.Stomach Diseases: Pathological processes involving the STOMACH.Dyspepsia: Impaired digestion, especially after eating.Endoscopy, Gastrointestinal: Endoscopic examination, therapy or surgery of the gastrointestinal tract.Hypnosis, Anesthetic: Procedure in which an individual is induced into a trance-like state to relieve pain. This procedure is frequently performed with local but not general ANESTHESIA.Gastritis, Atrophic: GASTRITIS with atrophy of the GASTRIC MUCOSA, the GASTRIC PARIETAL CELLS, and the mucosal glands leading to ACHLORHYDRIA. Atrophic gastritis usually progresses from chronic gastritis.Stomach Ulcer: Ulceration of the GASTRIC MUCOSA due to contact with GASTRIC JUICE. It is often associated with HELICOBACTER PYLORI infection or consumption of nonsteroidal anti-inflammatory drugs (NSAIDS).Helicobacter pylori: A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus CAMPYLOBACTER, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus HELICOBACTER. It has been officially transferred to Helicobacter gen. nov. (see Int J Syst Bacteriol 1989 Oct;39(4):297-405).Stomach Neoplasms: Tumors or cancer of the STOMACH.Helicobacter Infections: Infections with organisms of the genus HELICOBACTER, particularly, in humans, HELICOBACTER PYLORI. The clinical manifestations are focused in the stomach, usually the gastric mucosa and antrum, and the upper duodenum. This infection plays a major role in the pathogenesis of type B gastritis and peptic ulcer disease.Endoscopes, Gastrointestinal: Instruments for the visual examination of the interior of the gastrointestinal tract.Conscious Sedation: A drug-induced depression of consciousness during which patients respond purposefully to verbal commands, either alone or accompanied by light tactile stimulation. No interventions are required to maintain a patent airway. (From: American Society of Anesthesiologists Practice Guidelines)Gastritis: Inflammation of the GASTRIC MUCOSA, a lesion observed in a number of unrelated disorders.Antacids: Substances that counteract or neutralize acidity of the GASTROINTESTINAL TRACT.Stomach: An organ of digestion situated in the left upper quadrant of the abdomen between the termination of the ESOPHAGUS and the beginning of the DUODENUM.Gastrointestinal Hemorrhage: Bleeding in any segment of the GASTROINTESTINAL TRACT from ESOPHAGUS to RECTUM.Pepsinogen A: This is one of 2 related pepsinogen systems in humans and is also known as pepsinogen. (The other is PEPSINOGEN C.) This includes isozymogens Pg1-Pg5 (pepsinogens 1-5, group I or products of PGA1-PGA5 genes). This is the main pepsinogen found in urine.Gastric Mucosa: Lining of the STOMACH, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. The surface cells produce MUCUS that protects the stomach from attack by digestive acid and enzymes. When the epithelium invaginates into the LAMINA PROPRIA at various region of the stomach (CARDIA; GASTRIC FUNDUS; and PYLORUS), different tubular gastric glands are formed. These glands consist of cells that secrete mucus, enzymes, HYDROCHLORIC ACID, or hormones.Endoscopy, Digestive System: Endoscopic examination, therapy or surgery of the digestive tract.Biopsy: Removal and pathologic examination of specimens in the form of small pieces of tissue from the living body.Capsule Endoscopy: Non-invasive, endoscopic imaging by use of VIDEO CAPSULE ENDOSCOPES to perform examination of the gastrointestinal tract, especially the small bowel.Gastrectomy: Excision of the whole (total gastrectomy) or part (subtotal gastrectomy, partial gastrectomy, gastric resection) of the stomach. (Dorland, 28th ed)Referral and Consultation: The practice of sending a patient to another program or practitioner for services or advice which the referring source is not prepared to provide.Esophagitis: INFLAMMATION, acute or chronic, of the ESOPHAGUS caused by BACTERIA, chemicals, or TRAUMA.Gastrointestinal Diseases: Diseases in any segment of the GASTROINTESTINAL TRACT from ESOPHAGUS to RECTUM.Peptic Ulcer: Ulcer that occurs in the regions of the GASTROINTESTINAL TRACT which come into contact with GASTRIC JUICE containing PEPSIN and GASTRIC ACID. It occurs when there are defects in the MUCOSA barrier. The common forms of peptic ulcers are associated with HELICOBACTER PYLORI and the consumption of nonsteroidal anti-inflammatory drugs (NSAIDS).Duodenal Ulcer: A PEPTIC ULCER located in the DUODENUM.Metaplasia: A condition in which there is a change of one adult cell type to another similar adult cell type.Outpatient Clinics, Hospital: Organized services in a hospital which provide medical care on an outpatient basis.Anti-Ulcer Agents: Various agents with different action mechanisms used to treat or ameliorate PEPTIC ULCER or irritation of the gastrointestinal tract. This has included ANTIBIOTICS to treat HELICOBACTER INFECTIONS; HISTAMINE H2 ANTAGONISTS to reduce GASTRIC ACID secretion; and ANTACIDS for symptomatic relief.Waiting Lists: Prospective patient listings for appointments or treatments.Endoscopy: Procedures of applying ENDOSCOPES for disease diagnosis and treatment. Endoscopy involves passing an optical instrument through a small incision in the skin i.e., percutaneous; or through a natural orifice and along natural body pathways such as the digestive tract; and/or through an incision in the wall of a tubular structure or organ, i.e. transluminal, to examine or perform surgery on the interior parts of the body.Abdominal Pain: Sensation of discomfort, distress, or agony in the abdominal region.Colonoscopy: Endoscopic examination, therapy or surgery of the luminal surface of the colon.Family Practice: A medical specialty concerned with the provision of continuing, comprehensive primary health care for the entire family.Pyloric Antrum: The region between the sharp indentation at the lower third of the STOMACH (incisura angularis) and the junction of the PYLORUS with the DUODENUM. Pyloric antral glands contain mucus-secreting cells and gastrin-secreting endocrine cells (G CELLS).Retrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.Appointments and Schedules: The different methods of scheduling patient visits, appointment systems, individual or group appointments, waiting times, waiting lists for hospitals, walk-in clinics, etc.Gastrins: A family of gastrointestinal peptide hormones that excite the secretion of GASTRIC JUICE. They may also occur in the central nervous system where they are presumed to be neurotransmitters.Esophagus: The muscular membranous segment between the PHARYNX and the STOMACH in the UPPER GASTROINTESTINAL TRACT.Patient Satisfaction: The degree to which the individual regards the health care service or product or the manner in which it is delivered by the provider as useful, effective, or beneficial.Breath Tests: Any tests done on exhaled air.Gastroesophageal Reflux: Retrograde flow of gastric juice (GASTRIC ACID) and/or duodenal contents (BILE ACIDS; PANCREATIC JUICE) into the distal ESOPHAGUS, commonly due to incompetence of the LOWER ESOPHAGEAL SPHINCTER.Esophageal Neoplasms: Tumors or cancer of the ESOPHAGUS.Medical Audit: A detailed review and evaluation of selected clinical records by qualified professional personnel for evaluating quality of medical care.