Anticholinergics act by blocking muscarinic receptors in the smooth muscle of the airways and inhibiting vagal tone.

抗胆碱药作用于气道平滑肌上的特定毒蕈碱受体，以抑制迷走张力。

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Airway smooth muscle (ASM), existing in the trachea and in the bronchial tree up to the terminal bronchioles, serves as an important structural effector tissue to regulate bronchomotor tone.

呼吸道平滑肌可见于气管至末梢细支气管中，它被认为是调节支气管运动张力的重要组织。

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But when you look in magazines like GQ you see a smooth figure, which shows off the definition of muscle tone.

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