Blood vessels in the head tighten to stop the loss of body heat and then relax to let blood flow rise; that sudden rush of blood is what causes the headache.

头部的血管收紧以阻止身体热量的流失，然后放松让血液流动起来，血液的突然涌入是引起头痛的原因。

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But when researchers blocked production of that heat shock protein and let mosquitoes feast, the blood meal sat longer in their guts.

但是当研究者阻止了那种热休克蛋白的产生并让蚊子吸食的时候，所吸食的血在它们的肠道里待的时间更长。

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That is especially true in the heat, when blood vessels in the legs are distended and blood tends to pool in the feet, making the flow of blood up to the head even more difficult.

在高温下这更明显，因为腿部血管膨胀大量血液流向足部，使得向头部输送血液变得更难。

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