1781年Fontana首先描述了核仁是均匀,圆形的核内小体,H、E染色时对伊红有亲和力。核仁在细胞分裂间期有规律性变化。核仁消失于细胞分裂前期,出现于细胞分裂的末期。电镜下观察,核仁表面没有膜包绕,裸露于核内,以海绵状网为支架,腔隙连通,腔隙内物质与核液相混淆。海绵状网由纤维和颗粒所组成,颗粒的直径为 Fontana 1781 first described the nucleoli are uniform, round nucleosomes, H, E affinity to eosin affinity. Nucleolus in the cell division between the regular changes. Nucleolus disappeared in the pre-cell division, appeared in the late cell division. Electron microscopy showed that the surface of the nucleolus was surrounded by no membrane and was exposed in the nucleus. The spongy net was used as the scaffold, and the lacunar communication was established. The substance in the lacunar space was confused with the nuclear liquid phase. Spongy network consists of fibers and particles, the diameter of the particles