Attention to methology: fundamental criteria for studies in gastroenterology. Measurement of protein synthesis in the gastrointestinal tract. Analytical subcellular fractionation. Intestinal perfusion techniques. Assessing intestinal absorptive capacity and permeability in vivo. Measurement of human intestinal secretion and absorption in vitro. Ambulatory oesophageal and gastric pH monitoring. Evaluation of cytokine profile in the gastrointestinal tract. Ion transport in the gastrointestinal tract. Motility measurements. Helicobacter pylory: Methods of detection and study. Doppler sonography. Techniques of endoscopic ultrasonography in investigating gastrointestinal pathologies and therapeutic options. Metabolic studies on isolated intestinal tissue. Fibre optic confocal imaging (foci) for in vivo subsurface microscopy of the colon. Stable isotopes in the study of intestinal metabolism: Digestion, absorption and intestinal nutrient metabolism. Studying the basement membrane. Lipid peroxidation measurement in gastrointestinal tissue. Microdialysis as applied to the gastrointestinal tract. Salivary secretion: Investigative techniques. Mesenteric lymph node studies. Measuring cell proliferation. Isolation of intestinal smooth muscle cells. Use of argyrophilic nucleolar organizer region (AgNOR) staining techniques. In situ hybridization techniques as applied to the gastrointestinal tract. Diagnostic morphological methods: Use of immunomorphological and enzymohistochemical methods for a single disease entity. Immuno electron-microscopy in gastro-entero-pancreatic cells with reference to connexins 32 and 26. Immunocytochemical investigation of paraffin-embedded tissue. Fluorescent microscopy of immune cells in the Peyer's patches and small intestines in immunodefiency. Flow cytometry: Clinical and experimental applications to intestinal pathologies. Three dimensional analysis of epithelial cell proliferation. In vitro uptake of nutrients by human duodenal biopsies with special reference to iron. The future direction of pathology: personal perspectives.