Microscopic view, duodenal mucosa, intact villous architecture, detailed microscopic structure, finger-like projections, intestinal epithelial cells, microvilli on surface, Brunner's glands, lymphoid cells, blood vessels, lamina propria, muscularis mucosae, submucosal layer, soft focus, warm color tone, high magnification, scientific illustration, educational content, 3D reconstruction, anatomical accuracy, realistic texture, detailed labels.