It usually occurs before the age of 40, often during teenage years.

这种情况通常在40岁之前发生，在青少年时期。

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It usually occurs between 2 weeks and 4 months following the stressor.

通常发生在压力出现后的2周到4个月之间。

youdao

It usually occurs in winter, when a creature does not move for weeks or months continuously.

它通常发生在冬天，当一个生物不行动持续数周或数月。

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If it reflects economic fundamentals, then it implies that when important global news occurs, it is usually the sort of news that makes markets more volatile rather than stabilising them.

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It is found among people of all ages and classes and usually occurs after people experience some kind of financial upset, Dr Burchell added.

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Gupta said it was rare for teens to display symptoms of the disease, which usually occurs in young children.

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