过期妊娠胎盘的超微结构观察

本文选择8例过期妊娠胎盘进行超微结构观察，其改变主要有合体细胞微绒毛形态不规则，微绒毛变矮，部分区域微绒毛稀少，甚至消失。合体细胞浆内粗面内质同明显扩张，吞饮泡减少，线粒体的体积缩小，数量减少。局灶性的合体细胞坏死及细胞滋养层细胞增生。绒毛间质水肿，血管内皮细胞收缩并向腔内突出而导致管腔变小，纤维组织增生以及滋养层基底膜与血管基底膜之；司出现大小不一的囊泡。上述改变都影响到母子血液进行物质交换和胎儿的发育。此外对上述改变的发时机理进行一厂初步探讨。

ULTRASTRUCTURAL OBSERVATION OF THE PLACENTA IN PROLONGED PREGNANCY

We chose 8 cases of placentaes from proionged pregnancies for electron-microscop-ic study. The study has shown an irregularity shape and shorter syncytial microvilliThere is a paucity and disappearance of syncytial microvilli in some areas, dilatation ofsyncytial endoplasmic reticuium,decreased pinoc,,totic vesicles,an reduced size and num-ber of syncytial mitochondria, focal syncytiai, necrosis, hyperplasis of cytotrophoblasticcells, irregularity thicking of trophoblastic basement membrane, hydropic stromal offoetal villous,the endothelial cells of capiilary were contracted with cytoplasm protrud-ing bubously into,and narrowing lumen of the vessei in foe tai villous. The villous stromashowed an increase of collagen and appeared to be big or small vesculae between the tro-phoblastic basement membrane and the capillary basement melnbrane. These morpholog-ical changes will effect materno-foetal transfer and foetal growth. In addition,we dis-cussed inopcing mechanism of the microphoiogic changes.