Ⅱ.人类胚胎睾丸组织发生的形态学观察

Ⅱ.MORPHOLOGICAL STUDY OF THE HISTOGENESIS OF HUMAN EMBRYONIC TESTIS

用36例人类胚胎睾丸标本研究了睾丸的组织发生过程。结果显示,5周时原始生殖细胞迁移到性腺。6.5周后睾丸内出现白膜和睾丸索。5～8周表面上皮含有原始生殖细胞。14周后某些标本的睾丸索内出现管腔。8周时出现Leydig细胞,11～14周数量最多,18周后明显减少。20周后出现睾丸小叶,23周后直细精管和睾丸网内出现管腔。

The histogenesis of human embryonic thymus was studied with 58 embryonic thymuses.The results are as follows:from 6 to 8 weeks of gesta- tion the thymus is unlobulated and has no differentiation of cortex and medulla。 At 8 weeks lymphocytes are found in the thymus.At 11 weeks the thymus is lobulated and cortex and medulla could be distinguished.The Hassall′s corpuscles begin to appear at 13 weeks and are found in numbers at the deep portion of the medulla by 17-18 weeks.The aggragated.Hassall′s corpuscles can be found in the medulla after 19 weeks.There are numerous acidophilic granulocytes within the thymus,especially near the blood vessels in trabe- culae after 20 weeks.