The sudden onset of back pain following an injury is suspicious for a fracture.

在外伤后突然出现背部疼痛要怀疑骨折。

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Symptoms worth worrying about Sudden onset of severe central chest pain for ten minutes or more, which may spread to arms, neck or jaw.

值得担心突然发生严重中央胸痛10分钟或更长时间，这可能蔓延至手臂，颈部或颌部的症状。

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Military analysts know full well that a sudden onset of famine is one of the surest triggers for civil unrest and all out war.

FORBES: Peak Oil and ERoEI: Still Nonsense