原文视听

The discovery of undesired effects is, however,
然而 药物出现不理想的作用
intrinsic to the experimental nature of medicine.
也是源于药物试验性的本质
Clinical trials are done on thousands of people,
临床试验在几千人身上进行
but some side effects are only found
然而有些副作用
when hundreds of thousands take them,
只有上百万的人服用以后
when the drug comes to the market.
也就是药物进入市场之后才会被发现
You might start picking up side effects
你可能会出现一些副作用
that you couldn't have anticipated,
可能是一些意料之外的
that you didn't know, that are relatively rare
你不了解的 很罕见的副作用
but nonetheless can sometimes be important.
却有可能很重要
Drug development is an ongoing clinical trial
药物发展就是在不断的进行临床试验
in which we all play a part.
我们都是试验的一份子
There's no such thing as a totally safe medicine.
是药三分毒
There's no such thing as a
根本没有一种药物
medicine that we know absolutely everything about
我们能了解它的一切
and therefore there is some uncertainty, and that persists.
因此有一些不确定因素 且将持续存在
Because this goes to the heart of what medicines are.
因为这源于药物的本质
When you make a medicine,
你在制造药物的过程
you're trying to disrupt a fundamental biological process.
你要试图打乱基本的生物进程
That's a pretty profound change.
这是个复杂的变化

重点解释

Clinical trials are done on thousands of people,临床试验在几千人身上进行

thousands of数千的 ...

There are thousands of awnings on the sea beach.

沙滩上有许多遮阳篷。

The liberal candidate romped through with thousands of votes to spare.

自由党候选人轻易获胜，超出选票数以千计。

You might start picking up side effects你可能会出现一些副作用

pick up得到

I am able to pick you up on the short wave radio.

我能用短波收音机收听到你的信号。

The dog easily picked up the scent of the murderer.

狗毫不费力地嗅出了谋杀者的气味。

we all play a part.我们都是试验的一份子

play a part扮演一个角色； 在 ... 中起作用

Hopefully, if he can stay fit he could play a part.

希望,他能很健康,能够成为队中的一部分。