英语语法分析

MAIN OUTCOME MEASURES: the morphological changes of cryptorchidism, and the sorting results of spermatogonial stem cells.

主要观察指标：隐睾的形态学变化，精原干细胞分选结果。

The feeder layers of bone marrow stromal cells allowed spermatogonial stem cells to proliferate well and remain undifferentiated.

结果原代的小鼠培养骨髓基质细胞能很好的维持精原干细胞的非分化性扩增。

This article reviews recent advances in studies of the use of embryonic stem cells and spermatogonial stem cells in male reproduction.

本文就近年来胚胎干细胞和精原干细胞在男性生殖中的研究进展作一介绍。