文档介绍：Chapter 1 Introduction
I.     What’s histology?
II.    Why we study it ?
III.   How to study it ?-Histological methods.
I. What’s histology?
Histology (Greek words):
/histo-tissue
/logia-study of ,or knowledge of
So, histology means the knowledge of tissue, is a branch of Anatomy.
Anatomy:
---gross anatomy
---microscopic anatomy
Structures related to function. So, exactly, Histology is a science which study the microstructure and the relationship between the structure and function of human being.
Cell: smallest unit of structure and function of body
↓
tissue: group of cell+extracellular ground substance
four basic tissue:
---epithelium
↓---connective tissue
---muscular tissue
---nervous an: made up of tissue, have special shape, structure and function
↓
system: organs Which have related function get together.
’s Embryology?
Embryology is a kind of science which study the processes and the regulations of the development of human fetus.
III.    How to study it- histological methods
---Development of histology deponds on the development of technique.
---Histology studies the microstructures. So, we should have the aid of microscope to study. Several types of microscopes are available. According to the light source used, microscopes can be basally classified as:
light microscope(LM)
electron microscope(EM)
1. structure of Microscope
LM EM
---useful magnification: 1500X 800,000X
---resolution:
2. Preparation of tissue for LM
The most routine one is paraffin section stained with hematoxylin and eosin(H&E)
The steps:
a. Obtaining th specimen: fresh, small pieces ( less than 5mm3)-tissue block
b. Fixation: fixatives: use formalin or Bouin’s to preserve anisation
c.  Dehydration: use ethyl alcohol to get rid of water of tissue and cell
d.  Clearing: use xylene to get rid of alcohol
*alcohol and xylene are embedding mediums
e.  Embedding: firstly, heat the paraffin, make it melt, then put tissue block into melted paraffin, allow par