(单词翻译:单击)
Donating blood is a great way to help others and it's easy to do if you're relatively healthy.
献血是帮助别人的好方法，如果你相当健康的话，想献血也很简单。
Of course, some people aren't able to donate blood due to medical conditions or because they're taking prescription medications.
当然，一些人由于医疗条件原因或者由于他们正在服用处方药而无法献血。
But even basic over-the-counter medicine can stop you from donating parts of your blood.
但即使是基本成药也能阻挡你献血。
Like, you can't donate platelets if you've recently taken aspirin.
比如，如果你近期服用了阿司匹林，你就无法捐献血小板。
Because even though you might have just taken it for a headache,
因为就算你是因为头痛而服用阿司匹林，
aspirin also effects the rest of your body including your platelets.
阿司匹林同样会影响到你的身体，包括你的血小板。
When you're gonna cut, it's your platelets also called thrombocytes that are mostly responsible for stopping any active bleeding,
当你被切伤，血小板，也被称为凝血细胞，就主要负责阻止活动性出血，
along with other proteins they clump up and bind together making a scab for your open wound.
其他蛋白质团成小块并粘合在一起让你裸露的伤口结痂。
When someone has a low platelet count that puts them at risk of severe bleeding, even for a less serious injury.
当某人血小板参数低时，即使是并不严重的伤口，都有严重出血的风险。
That's where donations come in.
此时献血者就要加入了。
Unfortunately, you'll probably be turned away from donating if you've taken aspirin too recently
不幸的是，如果你近期服用了阿司匹林，可能也会被拒之门外不能献血
because it stops your platelets from working normally.
因为阿司匹林让你的血小板无法正常工作。
Aspirin is a complicated molecule made of carbon, oxygen and hydrogen,
阿司匹林是一种由碳、氧和氢组成的复杂分子，
it's used to relieve pain and for patients at risk for recurring strokes or heart attacks.
被用来缓解病人反复中风或心脏病的疼痛。
People have been using it since the 1890s but it wasn't until the 1970s that scientists actually understood how it works.
自1890年代人们就开始使用阿司匹林，但直到1970年代，科学家们才真正了解它是如何工作的。
The drug blocks an enzyme called COX-1 that reduces the production of prostaglandins,
阿司匹林封锁一种被称为COX-1的酶，这种酶能减少前列腺素的产生，
hormone-like compounds that normally cause inflammation and pain
前列腺素是一种类似激素的化合物，通常能够导致炎症和疼痛
blocking those compounds is what helps your headache.
阻止了这些化学物质就能帮助缓解你的头疼。
But the aspirin also inhibits the protein thromboxane.
但阿司匹林也能抑制蛋白质血栓素。
Thromboxane helps create blood clots and scabs by constricting your blood vessels
血栓素能够通过压缩你的血管和聚集血小板
and recruiting platelets to clump together.
帮助创造血凝块和结痂。
So if you take aspirin which stops thromboxane that prevents blockages from forming in your blood vessels and keeps your blood flow and free.
如果你服用了阿司匹林，抑制了血栓素，就阻挡了你血管内堵塞的形成并阻挡了你血液的自由流动。
That's why it's so helpful in preventing heart attacks which are caused by blood clots and so harmful for hospital patients.
因此，阿司匹林有助于预防由血凝块导致的心脏病，但对住院患者确实有害的。
Donated platelets are often used for cancer patients or for complications in surgery
捐献的血小板通常被用于癌症病人或手术的并发症
so hospitals need to be completely sure that they'll actually work and will prevent excessive bleeding
因此医院需要完全确定捐献的血小板能够正常运用并能够预防失血过多
and if your platelets aren't clumping together like normal,
如果你的血小板无法正常聚集，
you can see why donating them to someone in need might be a problem.
你就会发现将这些血小板捐给需要的人可能会引发问题的原因。
If you're interested in donating platelets,
如果你对捐献血小板感兴趣，
most donor banks suggest waiting about 48 hours after taking aspirin to let the drugs effects wear off
大部分捐献库都会建议，在服用阿司匹林后等待48小时以让药品效果退去
so that your platelets can gain back their regular clotting cells.
让你的血小板重新获取正常的凝血细胞。
But if you're scheduled to donate whole blood everything not just the platelets and you have a headache
但如果你计划好要去捐献全血，包括血小板，而如果正好又头疼的话
no worries, whole blood transfusions are often used in more general cases
别担心，全血输血通常被用于更加普通情形
where the clotting property of blood isn't necessarily the main thing they need.
这种情况下血液的凝血属性并不是他们需要的主要物质。
So if your platelets don't work normally, it's not as much of a problem.
因此如果你的血小板无法正常工作，也不是很大的问题。
For such a simple and easily available medicine, aspirin does a lot more to your body than you might think
这样一种简单易得的药，阿司匹林确实比你想的要重要
but as long as you plan ahead, you can still go forth donate and help those in need.
但是只要你做好提前计划，你还是可以去献血帮助那些有需要的人。
