医学课件Histology ＆ Embryology.pptVIP

Histology ＆ Embryology Chapter 1 ??Definition--- What’s the histology? ??Significance--- Why we study it? Methods--- How to study it ? Histology (Greek words): histo-- tissue -logy-- study of or knowledge of Histology is a science which study the normal microstructure of human being and the relationship between the structure and its function. Anatomy: ---gross anatomy ---microscopic anatomy cell: smallest unit of structure and function of body ↓ tissue: group of cells and extracellular ground substance ↓ organ: made up of tissue, has special shape, structure and function ↓ system: organs which have related function get together. II. Significance The basis for other medical courses --physiology(生理学） --pathology（病理学） 1. microscope light microscope (LM) electron microscope (EM) Unit used in microscope 1μm=1/1000 mm 1 n m=1/1000μm Maximum resolution Light microscope: 0.2μm Transmission electron microscope: 0.2nm Scanning electron microscope: 5nm Light microscope  1). Tissue preparation (paraffin section preparation) Specimen: as fresh as possible Fixation: formalin solution Dehydration: replace the water in the tissue by alcohol Clearing: replace the alcohol by by xylene Embedding: replace the xylene with melted paraffin Sectioning staining other preparations  2). H-E Staining Hematoxylin: basic dye (blue) Eosin: acid dye (red) Basophilia: components bonded by basic dye (H) blue （nuclear chromatin basophilic substance in cytoplasm） Acidophilia: components bonded by acidic dye (E); pink (cytoplasm collagenous fiber) Neutrophilia: do not stain with both basic and acid dyes H-E Staining Electron Microscopy A. Transmission Electron Microscope (TEM) light source: a beam of electrons instead of visible light. Section