【摘要】 目的本研究通过对人胚发育过程中大脑皮质神经细胞及突触超微结构变化的研究,揭示神经元生长发育过程的机理,进而探讨神经发育与先天性神经系统疾病的相关关系,为预防先天性神经系统疾病提供理论依据。方法本研究拟采用收集的3、4、5、6、7个月不同胎龄的大脑组织标本,分别从胎儿大脑皮质,以中央前回为界取第一运动区,利用电镜超薄切片技术观察人胚胎不同月龄大脑皮质神经元及突触的超微结构。结果随胎龄增加,神经细胞体积增大,突起数量增多,长度增加,各种细胞器逐渐增多,其结构和功能逐步完善,突触结构也趋于成熟。结论6、7个月龄是发育的重要时期,也是发生先天性畸形的危险时期。更多还原

【Abstract】 Objective To disclose the mechanism of neuron development by investigating ultrastructural changes of cerebral cortex during fetal development,then to explore the correlation between neuron development and congenital nervous system diseases.Methods The cerebral tissue samples of 3,4,5,6 and 7-monthold fetuses were collected,whose nervous systems showed no lesion and deformity.The samples were gained from motor area which limited by precentral gyrus.Electronic microscope was used to observe the ultrastructure of cerebral neurons and synapse.Results With the increase in month,cellular volume of neurons was increased,with more and longer spines.Noticeable morphism variations in the nucleolus and organelle in some neurons could be observed under electron microscope;with the increase in month,the structure and function of synapse were gradually completed.Conclusion The 6 and 7-month stage of fetus is vital for the fetal development.In this period congenital malformations are taken place quite often.更多还原