pre-icterus stage

例句：

1. 1. The patient was in the pre-icterus stage when he was admitted to the hospital.
   病人入院时处于前发绀期。
2. 2. During the pre-icterus stage, the patient's condition improved significantly.
   在发绀前期，患者的病情有了很大的改善。
3. 3. The research focused on the pre-icterus stage of the disease.
   该研究关注了疾病的前发绀期。