VOA常速英语2007-Broccoli Extract May Help Prevent Skin Cancer

By Jessica Berman
Washington
23 October 2007

Researchers say that an extract made from broccoli¹ sprouts³ may prevent skin cancer when applied⁴ directly to the skin.  VOA's Jessica Berman reports scientists say broccoli contains a chemical that stimulates⁵ the body's natural anti-cancer ability.

According to scientists, broccoli contains a chemical called sulphoraphane, which activates⁶ cancer-fighting enzymes⁷ inside cells.  Researchers say the richest source of sulphoraphane is contained in sprouts.

In a demonstration⁸ of the plant's anti-cancer properties, investigators⁹ smeared¹⁰ broccoli sprout² extract on the skin of six volunteers for three days, and then exposed them to high doses of ultraviolet radiation, which is the leading cause of skin cancer. 

They found there was an average 37 percent less redness and sunburn in the patches covered by broccoli extract.  Redness and sunburn are an indication of skin damage that could lead to cancer.

The results of the study are published in the journal Proceedings¹¹ of the National Academy of Sciences.

Paul Talalay is a Johns Hopkins University molecular¹² pharmacologist and the author of the study.  Talalay says sunscreen conferred no protection against the UV rays, but he says that does not mean people should stop using it. 

"We want to avoid under all circumstances people doing weird¹³ things like making broccoli sprout soup and applying to their skin and thinking that they will be protected against the sun," he said.  "They will have not have any protection whatsoever¹⁴, because it's a totally different mechanism¹⁵ and one cannot possibly substitute for the other."

Applied as a thick cream, sunscreen protects the skin by deflecting¹⁶ the sun's harmful rays.  But it must be constantly reapplied to remain effective. 

In contrast, Talalay says, a compound made of broccoli sprouts works by penetrating¹⁷ skin cells and stimulating¹⁸ their natural cancer-fighting mechanism.

Observers call the research promising¹⁹, but say more studies are needed because the results varied²⁰ considerably²¹ among participants, ranging from a low of eight percent to a high of 78 percent protection against sunburn.  Talalay disagrees.

"Everybody knows you go to the beach and you get fried and I go to the beach and nothing happens to me," he added.  "And we are in the same place.  So, the same experiment if done in a large number of individuals would be much more complex.  But I believe that the evidence certainly from animal studies is that we would get absolutely the same result."

Talalay believes if it works in the skin, a sulphoraphane extract from broccoli sprouts is very likely to act as a hedge against cancer in other organs.

Meanwhile, researchers say there are a number of challenges in making a sun cream from broccoli sprouts, not the least of which is figuring out how to get rid of the green tint²².

1 broccoli   

n.绿菜花，花椰菜

参考例句：

• She grew all the broccoli plants from seed.这些花椰菜都是她用种子培育出来的。
• They think broccoli is only green and cauliflower is only white.他们认为西兰花只有绿色的，而菜花都是白色的。

2 sprout   

n.芽，萌芽；vt.使发芽，摘去芽；vi.长芽，抽条

参考例句：

• When do deer first sprout horns?鹿在多大的时候开始长出角？
• It takes about a week for the seeds to sprout.这些种子大约要一周后才会发芽。

3 sprouts   

n.新芽，嫩枝( sprout的名词复数 )v.发芽( sprout的第三人称单数 )；抽芽；出现；（使）涌现出

参考例句：

• The wheat sprouts grew perceptibly after the rain. 下了一场雨，麦苗立刻见长。 来自《现代汉英综合大词典》
• The sprouts have pushed up the earth. 嫩芽把土顶起来了。 来自《现代汉英综合大词典》

4 applied   

adj.应用的；v.应用，适用

参考例句：

• She plans to take a course in applied linguistics.她打算学习应用语言学课程。
• This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。

5 stimulates   

v.刺激( stimulate的第三人称单数 )；激励；使兴奋；起兴奋作用，起刺激作用，起促进作用

参考例句：

• Exercise stimulates the body. 运动促进身体健康。 来自《简明英汉词典》
• Alcohol stimulates the action of the heart. 酒刺激心脏的活动。 来自《现代英汉综合大词典》

6 activates   

使活动，起动，触发( activate的第三人称单数 )

参考例句：

• Activates the window and displays it in its current size and position. 激活窗口，保持当前的大小及位置不变。
• Pulling out the alarm switch activates alarm and pushing it deactivates it. 闹钟的开和关是通过拔出和按入闹铃开关实现的。

7 enzymes   

n. 酶，酵素

参考例句：

• It was said that washing powders containing enzymes remove stains more efficiently. 据说加酶洗衣粉除污更有效。
• Among the enzymes which are particularly effective are pepsin, papain. 在酶当中特别有效的是胃朊酶、木瓜酶。

8 demonstration   

n.表明，示范，论证，示威

参考例句：

• His new book is a demonstration of his patriotism.他写的新书是他的爱国精神的证明。
• He gave a demonstration of the new technique then and there.他当场表演了这种新的操作方法。

9 investigators   

n.调查者，审查者( investigator的名词复数 )

参考例句：

• This memo could be the smoking gun that investigators have been looking for. 这份备忘录可能是调查人员一直在寻找的证据。
• The team consisted of six investigators and two secretaries. 这个团队由六个调查人员和两个秘书组成。 来自《简明英汉词典》

10 smeared   

弄脏； 玷污； 涂抹； 擦上

参考例句：

• The children had smeared mud on the walls. 那几个孩子往墙上抹了泥巴。
• A few words were smeared. 有写字被涂模糊了。

11 proceedings   

n.进程，过程，议程；诉讼(程序)；公报

参考例句：

• He was released on bail pending committal proceedings. 他交保获释正在候审。
• to initiate legal proceedings against sb 对某人提起诉讼

12 molecular   

adj.分子的；克分子的

参考例句：

• The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
• For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。

13 weird   

adj.古怪的，离奇的；怪诞的，神秘而可怕的

参考例句：

• From his weird behaviour,he seems a bit of an oddity.从他不寻常的行为看来，他好像有点怪。
• His weird clothes really gas me.他的怪衣裳简直笑死人。

14 whatsoever   

adv.（用于否定句中以加强语气）任何；pron.无论什么

参考例句：

• There's no reason whatsoever to turn down this suggestion.没有任何理由拒绝这个建议。
• All things whatsoever ye would that men should do to you,do ye even so to them.你想别人对你怎样，你就怎样对人。

15 mechanism   

n.机械装置；机构，结构

参考例句：

• The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。
• The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。

16 deflecting   

（使）偏斜， （使）偏离， （使）转向( deflect的现在分词 )

参考例句：

• A variety of mechanical surfaces have been employed for deflecting the exhaust jets of solid-propellant rockets. 人们已经用过各种类型的机械控制面来偏转固体推进剂火箭的排气流。
• If she made a leading statement, he was expert deflecting her into more impersonal channels. 只要她一开口，他就会巧妙地把她的话题转到与个人无关的问题上去。

17 penetrating   

adj.（声音）响亮的，尖锐的adj.（气味）刺激的adj.（思想）敏锐的，有洞察力的

参考例句：

• He had an extraordinarily penetrating gaze. 他的目光有股异乎寻常的洞察力。
• He examined the man with a penetrating gaze. 他以锐利的目光仔细观察了那个人。

18 stimulating   

adj.有启发性的，能激发人思考的

参考例句：

• shower gel containing plant extracts that have a stimulating effect on the skin 含有对皮肤有益的植物精华的沐浴凝胶
• This is a drug for stimulating nerves. 这是一种兴奋剂。

19 promising   

adj.有希望的，有前途的

参考例句：

• The results of the experiments are very promising.实验的结果充满了希望。
• We're trying to bring along one or two promising young swimmers.我们正设法培养出一两名有前途的年轻游泳选手。

20 varied   

adj.多样的，多变化的

参考例句：

• The forms of art are many and varied.艺术的形式是多种多样的。
• The hotel has a varied programme of nightly entertainment.宾馆有各种晚间娱乐活动。

21 considerably   

adv.极大地；相当大地；在很大程度上

参考例句：

• The economic situation has changed considerably.经济形势已发生了相当大的变化。
• The gap has narrowed considerably.分歧大大缩小了。

22 tint   

n.淡色，浅色；染发剂；vt.着以淡淡的颜色

参考例句：

• You can't get up that naturalness and artless rosy tint in after days.你今后不再会有这种自然和朴实无华的红润脸色。
• She gave me instructions on how to apply the tint.她告诉我如何使用染发剂。