There are 5 stages during the development of embryo, including the stage of 2-celled proembryo, multicellular proembryo, globular proembryo, pyriform proembryo, differential embryo and mature embryo.

胎发育经过二细胞、多细胞、形、梨形、分化和成熟阶段。

Granulocytic sarcoma (GS), also known as extramedullary myeloblastoma or chloroma is an unusual manifestation and represent soft tissue masses composed of immature cells of the granulocytic series.

粒性白血肉瘤也称为骨髓细胞瘤瘤，是一种少见的疾病。

The midgut gland cell differentiation occurs at Z2, There are 4 types of cells, i. e., embryonic cell (E-cell), fibrillar cell (F-cell), blister cell (B-cell) and resorptive cell(R-cell).

中肠腺小管上皮在Z2期细胞已有了分化，由4类细胞组成，即细胞(E细胞)、纤维细胞(F细胞)、泡状细胞(B细胞)和吸收细胞(R细胞)。