在制备超薄切片之前,有些生物样品需要制作半薄切片,在光镜下确定所要观察的结构,并在环氧树脂包埋块上对此结构进行准确的定位,避免盲目的超薄切片,从而提高电镜的观察效率。用环氧树脂包埋的生物样品,如果采用适宜的染色方法对半薄切片进行染色,在光镜下观察,可获得比石蜡切片保存的更多的结构 Before the preparation of ultrathin sections, some biological samples need to be made into semi-thin sections, and the structure to be observed under the light microscope is determined. The structure is accurately positioned on the epoxy embedded block to avoid blind and ultra-thin sections, Thus improving the observation efficiency of electron microscope. Epoxy resin embedded biological samples, if the use of appropriate staining half-thin sections were stained, observed under the light microscope, can be obtained than the paraffin sections to save more structure