At this point the upper stem has lost contact with the diaphragms. The valve should be opened to this point but not back seated.

在此时，上阀杆已经失去了同横膈膜的接触。阀门应该开启到这一点，但不能反向固定。

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Taking radiotherapy of tumor stem cells as a contact point, strategy designed by radiobiology can essentially solve this problem.

将肿瘤干细胞作为放射治疗的切入点，针对其放射生物学行为制订对策，才能从根本上解决问题。

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Toxicity: The major hazards of silane stem from its ability to spontaneously ignite on contact with air and its toxicological properties.

毒性：硅烷的主要危险来自它接触空气可以自发燃烧的能力和它的毒物学的性质。

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