Methods Epithelial cells were isolated from sample tissue by cold trypsinization and cultured in serum-free growth medium.

方法 织块用冷消化法离出尿路上皮，培养于血清生长培养基。

Methods Separate the embryonic fibroblast of mice and culture with the method of suspension culture and method of trypsinization.

方法取大鼠胚胎离成纤维,别采用悬液法和胰酶消化植块培养法对其进行培养。