已经证实术前戒烟至少8周可减少术后呼吸系统并发症。

This is evidenced by the decrease in postoperative respiratory complications in patients who have quit smoking cigarettes for at least 8 weeks before surgery.

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Cell - CT显微镜中，单个细胞嵌入到一种特殊玻璃管的凝胶中，玻璃管在一个固定相机前旋转，每旋转一周可拍摄许多照片。

In the Cell-CT microscope, each cell is embedded in a special gel inside a glass tube that rotates in front of a fixed camera that takes many pictures per rotation.

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所有吃剩下的东西都可以放进冰箱，可保鲜2至3周。

Whatever is left over may be put into the refrigerator, where it will keep for 2-3 weeks.

《柯林斯英汉双解大词典》

Two weeks after the Columbine massacre, Ludlow Colorado I got called before the U.S. Senate Commerce Committee to testify on the relationship of youth culture and violent entertainment.

科罗拉多可伦拜高中枪杀案，事发两周后,美国参议院商务委员会给我打电话,让我参加一场听证会,主题是青年文化和暴力性娱乐的关系。

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