按下Cmd和Opt键的同时击这个三角形符号，可以折叠或展开所有层级的群组文件夹。

Hold down Cmd + Opt + click on the triangle icon will collapse or expand all level layer groups.

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定做矫正器，来自桶形石膏夹制备的嘴和牙齿模具，显著降低呼吸暂停-呼吸减慢指数，而热塑性矫正器则无效。

The custom-made devices, created using a plaster cast of the patient's mouth and construction bites, significantly reduced the apnea-hypopnea index, whereas the prefabricated devices did not.

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在蜡台上设有特殊的成型片弹簧。弹簧夹口呈三角形状，蜡烛被固定在三角形内切圆位置上。

Its specially-shaped leaf spring constitutes a triangle with the candle being fixed in the position of inscribed circle of the triangle.

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