国人胎儿胸腺的生长发育

DEVELOPMENT OF HUMAN FETAL THYMUS

称量了14—38周共56例引产胎儿胸腺的重量并观察了6—38周共25例引产胎儿胸腺的组织结构,认为胸腺在胚胎时期生长速度较快。光镜观察,6周已出现胸腺的始基,第9周开始出现淋巴细胞,12周开始分叶,13周以后,皮质髓质渐趋分明并出现胸腺小体,15周后胸腺小叶增多变宽,新小叶形成旺盛,胸腺小体增多,至28周后结构已近似成熟。

ABSTRACT Human fetal thymuses were weighed at different stages of development from 14 to 38 weeks and their histolo gic structures were studied with light microscopy at different stages from 6 to 38 weeks of gestation. The thymus of the fetus develops and grows rapid ly. At the sixth week the thymus just began to develop; and at the ninthweek there appeared some lymphocytes; at 12 th week it was divided into lobules by connective septa; at 13 th week, cortex medu 11a, thymus corpuscles and some dide lymphocytes could be dis tin guished. Atl5 th week the lobules increased in number, became larg er, with, some newlobules appearing After 28 th week, the histolog ic structures had become similar to those of an adult.