To utilize the advantages of drug carriers of different sizes, a size switchable "ball-and-rod" drug delivery system was constructed, which could switch its size in response to enzymes in tumors. It would be a promising system with long circulation and deep penetration properties, which enable its application in tumor treatment.

中文翻译：

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新型“球杆” MSNs-pp-PEG系统的构建：具有粒径可切换功能的有前途的抗肿瘤药物递送系统。

为了利用不同大小的药物载体的优势，构建了大小可切换的“球杆”药物递送系统，该系统可以响应肿瘤中的酶来改变其大小。这将是一个有希望的系统，具有长循环和深穿透特性，使其能够在肿瘤治疗中应用。