It is not clear that such bloodletting is required.

目前尚不清楚否需要这样的放血。

Between the breach and the bloodletting, it quickly ran out of nitrogen.

先，再放血，我的氮气罐早已空了。

So, maybe all those bloodletting patients from the past didn't understand what improvements in biomarkers meant, but found that they felt a little better.

所以，也许过去所有放血的病人都不明白生物标记的善意味着什么，但他们发现自己感觉好了一点。

For 3,000 years, people have been cut or given leeches to let out the blood because they thought that would make people better.

在长达3000年的时间里，人们划破皮肤放血水蛭吸血，因为他们认为放血能够善他们的身体。

And I happen to see this really tiny study which had the unpromising name, sub-lethal behavior and physiological effects of the biomedical bleeding process on the American horseshoe crab, Limulus Polyphemus.

我碰巧看到了这项非常微小的研究，它的名称、亚致死行为以及对美洲鲎（Limulus Polyphemus）生物医学放血过程的生理影响都没有什么希望。