It's unclear why insomnia is linked to higher heart attack risk. Some suggest sleep problems affect heart attack risk factors such as high blood pressure and inflammation.

目前还不清楚为什么失眠症与较高的心脏病发作风险相关。有人认为睡眠问题可能影响了心脏病发作的相关因素，比如高血压和炎症。

youdao

No one in high command believed that German forces would attack in the sub zero temperatures and near blizzard conditions. As the pre-dawn attack comes, with communications down Sgt.

他们这个 94步兵师的班在小镇外的山脊掘豪固守，可是没有一个美军高层指挥官相信德军会在零下温度的暴风雪中进攻。

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The researchers said the hair cortisol levels were a better predictor of heart attack than established risk factors like high blood pressure.

VOA: special.2010.10.12

These include heart disease, heart attack,stroke,diabetes and high blood pressure.

VOA: special.2009.06.09

It includes heart attack, stroke and high blood pressure.

VOA: special.2009.07.15

All of those pieces point to a complex, multistep targeted attack from a high-resource organization.

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Our two vehicles were under attack, at high speed, by two other vehicles.

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The attack on a high-profile event in the heart of the capital is seen as a big symbolic blow to Somalia's attempts to reinvent itself on the international stage after years as a failed state.

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