Methods: The expression and distribution of GDF-9 in different developmental stages of rat ovary is examined by immunohistochemistry and Western blot.

• 方法：选择不同发育时期的大鼠卵巢，采用免疫组化和Western blot技术检测大鼠卵泡各发育阶段GDF-9蛋白表达情况及分布规律。