1. The patient experienced an intervital period of relative stability before the symptoms worsened again.

病人在症状再次恶化之前经历了一个相对稳定的症状间歇期。

2. The doctor observed an intervital phase during which the patient's condition seemed to improve temporarily.

医生观察到一个症状间歇期，病人的情况在此期间似乎暂时有所改善。