Because of its insidious onset, the diagnosis of this disease was usually delayed rendening treatment difficult.

此病起病隐匿，诊断时往往已是晚期，治疗困难。

youdao

Hepatocellular carcinoma is also a high malignancy with insidious onset, invasive fast-growing, high recurrence rate and fatality.

肝细胞肝癌具有起病隐匿，恶性程度高，侵袭性生长快速，治疗后易复发，病死率高等特点。

youdao

All patients had insidious onset and slow progression of behavioral and cognitive dysfunction accompanied by daytime somnolence and headache.

所有患者均起病隐匿，其行为和认知功能障碍的进展速度也较为缓慢，并伴有日间嗜睡和头痛症状。

youdao

Its onset is rapid and insidious, and it can be fatal within 24 to 48 hours of the first non-specific symptoms.

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