英语语法分析

The diagnosis is usually not made until the end of the catarrhal stage .

诊断通常在卡他期终了前尚不能作出。

Only fragmentary information on pathogenesis of bovine malignant catarrhal fever is available.

关于牛恶性卡他热的病理发生，仅能获得一些零星的资料。

Method: 39 cases of 56 ears suffered from chronic catarrhal otitis media were treated by the eustachian catheter.

方法：用咽鼓管导管治疗慢性卡他性中耳炎39例、56耳。