Research suggests that the reason for this could be the ageing effects of stress, and the persistent relaxation of facial muscles which can be an effect of long term anti-depressant use.

研究表明这种现象的原因可能是紧张导致的衰老效应，而脸部肌肉的持续松弛可能是长期服用抗抑郁药物的结果。

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And the principle, object and selection principle of technological parameters of stabilizing treatment for improving the anti stress relaxation ability are given.

分析改进抗应力松弛性能的稳定化处理的原理、目的要求及工艺参数的选择原则。

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