I was supposed to give Greene a free hand, but I couldn't go out on a limb by having him knocking on someone's door and telling them they had a tree in pain.

我本该让格林自由行动，但我不能任由他敲开某户人家的房门，告诉这些陌生人他们家里的一棵大树正疼痛难忍，最终把我自己也拖下水。

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They were really surprised to watch the effect of merely "knocking" off a few pain related sensory nerve cells.

他们惊讶的观察到，仅简单敲除一小部分痛觉相关感觉神经细胞所带来的效果。

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In this week's issue of the "Proceedings of the National Academy of Sciences, " FitzGerald has published experiments showing that knocking out a gene in mice might decrease the risk of heart attacks while inhibiting pain.

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