VOA常速英语:Nicotine Enhances Effects of Cocaine

短语讲解：

1. Dr. Amir Levine says there is some support for the gateway hypothesis, that adolescents begin drug use with alcohol and nicotine, then advance to marijuana and more serious drugs.

advance to发展到…; 使晋升到…, 使提前到…
例句：About 80 percent of the graduates advanced to senior high schools.
约有80%的毕业生升入了高中。

2. And then we were wondering whether that sequence, apart from having cigarettes more available and alcohol more available, whether there was also a biological effect of these drugs on other drugs later on down the line.

apart from除去，撇开…来说(表示除…以外尚有)，此外，加之
例句：Apart from some spelling mistakes, the composition is fairly good.
除了一些拼写错误, 这篇文章写得很不错。
later on以后
Can we talk about it later on?
我们能否以后谈论这件事?

3. To find an answer, Levine and his colleagues used laboratory mice, and added nicotine to their water.

add to增加, 加强
例句：The office looked exactly the same as before, only some charts were added to the wall.
办公室里还是那个老样子, 只是墙上多了一些图表。

4. Then they injected the mice with cocaine and compared their behaviors with drugged mice that had not gotten the nicotine.

compare with (把…)与…相比
例句：My knowledge is not to be compared with yours.
我的知识不能与你的相比。

5. And it sort of makes a little bit of sense, why people start with nicotine and then go on to cocaine.

go on继续下去
例句：If he goes on like this he'll lose his job.
如果他继续这样下去,他会丢掉差事的。

6. Because if they're smoking nicotine and they begin with cocaine, they get a wow!

begin with以…开始, 从…开始
例句：The teacher began his class with a question.
老师以一个问题开始他的讲课。

7. Nicotine has a direct effect on DNA, Amir Levine explains, essentially exposing genes that are linked to addiction.

link to与…连接; 联系
例句：Fingerprints linked the suspect to the crime.
指纹使嫌疑犯与犯罪联系起来。

8. So then, when you give cocaine, certain genes that are involved in addiction are greatly expressed, much more than if you give cocaine by itself.

involve in使参与〔陷入, 牵扯到〕
例句：She was involved in working out a puzzle.
她在聚精会神地解一道难题。

9. And she saw that if you started smoking before you started cocaine, you are much more likely to become addicted to cocaine.

addict to上瘾；沉溺于
例句：She is addicted to television.
她对电视入了迷。

10. Co-author Eric Kandel says a deeper understanding of the biological process of addiction may lead to more effective treatments.

lead to导致
例句：Smoking can lead to lung cancer.
抽烟可能导致肺癌。