胎儿肝脏发育的组织学及形态计量学和超微结构观察

目的了解胎儿肝脏的发育状况，探讨肝细胞与造血灶之间的关系。②方法选用２４例不同发育时期的胎儿，进行组织学、形态计量学和超微结构观察。③结果随胚龄增长胎儿肝细胞数量增多，体积增大，核质比减小，细胞器渐丰富；细胞排列有序且始终有明、暗细胞之分。肝血窦腔隙开始较大，造血组织在胚胎早中期较丰富；胚胎发育后期，肝血窦渐变窄，造血组织明显减少。胆小管发育至胚胎晚期，封闭其管腔的紧密连接发育完善。④结论肝细胞发育过程中始终有明、暗肝细胞之分。胎儿肝脏在胚胎早期和中期均有造血功能。发育中的肝细胞及库普弗细胞与幼红细胞密切接触，可能为造血细胞的发育提供良好的微环境。

A HISTOLOGICAL MORPHOMETRICAL AND ULTRASTRUCTRAL STUDY OF THE DEVELOPMENT OF THE FETUS LIVER

Objective\ To know the development of the fetus liver and to study the relationship between the liver cells and the blood forming focus.\ Methods\ Twenty four fetuses at different developing stages were observed histologically, morphometrically and ultrastructurally.\ Results\ with the age increase of the fetus, the number of the fetus liver cells increased, the volume became larger, the karyoplasmic ratio decreased, the cell organ gradually became more plentiful, the arrangement of cells was in order and there was always differentiation between light and dark cells. The lacuna of the hepatic sinusoid was large and the blood forming tissue increased at the early and middle stages. At the last stage of fetus development, the hepatic sinusoid became narrower and the blood forming tissue decreased apparently. When the bile canaliculus developed to the last stage of the fetus, the tight junction closing the lumen developed into a perfect condition.\ Conclusion\ The results of this study show that the appearance and morphological characteristics of light and dark cells in the process of the liver cell development are different from those observed in the previous study. The fetus liver has blood forming function at the early and middle stages of the fetus development. The developing liver cells and kupffer cells are in close contact with the immature red cells, which may provide a good micro circumstance for the development of blood forming cells .