SCIENCE IN THE NEWS

SCIENCE IN THE NEWS
By

Broadcast: Tuesday, June 08, 2004

VOICE ONE:

This is SCIENCE IN THE NEWS, in VOA Special English. I'm Sarah Long.

VOICE TWO:

And I'm Bob Doughty¹. Today we talk about a medicine that has found new uses over time.

VOICE ONE:

 
Graphic² Image
And may find even newer ones. Learn the history of aspirin³, and the most recent findings, coming up.

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VOICE ONE:

More than two-thousand years ago, in ancient Greece, Hippocrates advised his patients about a way to ease pain. The great doctor told them to chew on the bark of the willow⁴ tree. The outer covering of the tree contains a chemical, salicylic acid.

By the seventeen-hundreds, people used willow bark to reduce high body temperatures.

In eighteen-sixty, researchers at the Bayer Company in Germany copied nature. They created acetyl salicylic acid. And they took a name from the spirea plant, which also contains the natural chemical. They called their new formula aspirin.

VOICE TWO:

Aspirin has been sold for more than a century as a treatment for headaches, muscle pain and high temperature.

In nineteen-eighty-two, a British scientist shared the Nobel Prize in Medicine in part for discovering how aspirin works. Sir John Vane found that aspirin blocks the body from making natural substances called prostaglandins.

Prostaglandins have several effects on the body. Some cause pain and swelling⁵ in damaged tissue. Others protect the lining⁶ of the stomach and small intestine⁷. Prostaglandins also make the kidneys, heart and blood vessels⁸ work well. But there is a problem. Aspirin works against all prostaglandins, good and bad.

VOICE ONE:

Scientists learned how aspirin interferes¹⁰ with an enzyme¹¹. One form of this protein makes the prostaglandin that causes pain and swelling. Another form of the enzyme creates the protective kind of compound. So aspirin can reduce pain and swelling in damaged tissues. But it can also harm the lining of the stomach and small intestine.

Aspirin competes these days with a lot of other pain medicines. Many people like to take acetaminophen. This is the active substance in products like Tylenol. Still, experts say aspirin does some things that the others cannot.

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VOICE TWO:

Many people take aspirin to reduce the risk of a heart attack.

Scientists say aspirin prevents tiny blood cells called platelets from sticking together to form clots¹². Clots can block the flow of blood to the heart or the brain. This can cause heart attacks or strokes.

The use of aspirin to reduce the risk of heart disease has grown in recent years. Yet one doctor noted¹³ this effect in the nineteen-fifties.

VOICE ONE:

The doctor was Lawrence Craven. He observed unusual bleeding among children who chewed on aspirin gum to ease pain after a throat operation. Doctor Craven believed they were bleeding because aspirin prevented the blood from thickening. He decided¹⁴ that aspirin might help prevent heart attacks caused by blood clots.

So Doctor Craven examined medical records of about eight-thousand people. He found no heart attacks or strokes among those who regularly took aspirin. Doctor Craven invited other scientists to test his ideas. But it was many years before large studies took place.

VOICE TWO:

Doctor Charles Hennekens of the Harvard Medical School in Boston, Massachusetts, led one of the studies. In nineteen-eighty-three, he began to study more than twenty-two-thousand healthy male doctors over the age of forty.

Half the doctors in the study took an aspirin every other day. The other half took what they thought was aspirin, but was just a sugar pill. Five years later, Doctor Hennekens reported that the men who took aspirin reduced their chances of a heart attack. However, the men who took aspirin also had a higher risk of bleeding in the brain.

VOICE ONE:

In recent years, a group of American medical experts examined studies on aspirin for the Department of Health and Human Services. The experts said people who have an increased risk of a heart attack should take a small amount of aspirin every day.

People who are most likely to suffer a heart attack include men over the age of forty and women over the age of fifty. People who weigh too much or smoke cigarettes are also at greater risk. So are people with diabetes¹⁵, heart disease, high blood pressure or high cholesterol¹⁶.

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VOICE TWO:

Aspirin may help someone who is having a heart attack caused by a blockage¹⁷ in the flow of blood to the heart. Aspirin thins the blood. This can permit blood to flow past the blockage in the artery¹⁸. But heart experts say people should seek emergency help immediately. They say an aspirin is no substitute for treatment.

Some people should not take aspirin. These include people who have stomach problems. Doctors say people who take other blood thinners or have bleeding disorders¹⁹ should not take aspirin either.

VOICE ONE:

Some studies have been done on the effects of taking aspirin during the first signs of a stroke. These studies showed some improvement in the condition of the patients. But can aspirin prevent strokes in healthy people?

The Archives of Neurology published a report in two-thousand about aspirin and stroke prevention. Robert Hart and others at the University of Texas at San Antonio examined studies of more than fifty-thousand healthy people.

Some of the people already had an increased risk of stroke, like high blood pressure. Others had no signs that they might suffer a stroke in the future.

VOICE TWO:

The researchers found that aspirin did not seem to prevent strokes, as long as people had no signs of blocked blood vessels in their brain. Doctors say aspirin may help prevent small strokes that result from such blockage. But the report said aspirin was linked to a small increase in the risk of bleeding in the brain. This can also cause a stroke.

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VOICE ONE:

Like other medicines, aspirin can cause problems, especially if taken in large amounts. The acid in the drug may damage the tissue of the stomach or intestines²⁰. Aspirin can also interfere⁹ with the healing of the cells. Some people develop severe bleeding.

Yet other research has found that aspirin may help prevent cancers of the stomach and intestines. Studies in the last twenty years have shown that people who take aspirin have unusually low rates of such cancers.

VOICE TWO:

One of the newest reports about aspirin involves the most common form of breast cancer. In May, researchers announced findings from a study of almost three thousand women in New York City. The study compared women who took aspirin several times a week to women who did not. Scientists from Columbia University say the aspirin users had a twenty-five percent lower rate of breast cancer.

One of the doctors involved in the study said aspirin appeared to reduce the production of estrogen. This female hormone²¹ is linked to up to seventy percent of all cases of breast cancer.

The Journal of the American Medical Association published the findings. But the researchers say they are not ready to advise women to take aspirin in hopes of protection against breast cancer.

VOICE ONE:

But doctors do often advise aspirin for patients at risk of diseases that result from blood clots, such as a heart attack. In May, a Harvard Medical School publication said that some people, however, get little or no protection from aspirin. The Harvard Heart Letter said this idea is so new that many doctors do not know about it, or they are waiting for more research. Still, the report advised that it is not too early for people to ask about being tested to see if they respond to aspirin.

In any case, medical experts say no one should take aspirin for disease prevention without first asking a doctor. Aspirin is sold in different strengths. It can interfere with other drugs. And it is not safe for everyone. Most pregnant women are told to avoid aspirin. Children who take aspirin can suffer a serious disease called Reye's syndrome²².

Yet, even with its problems, aspirin remains²³ one of the oldest, least costly²⁴ and most widely used drugs in the world.

(THEME)

VOICE TWO:

This SCIENCE IN THE NEWS program was written by Caty Weaver²⁵ and produced by Cynthia Kirk. This is Bob Doughty.

VOICE ONE:

And this is Sarah Long. Join us again next week for more news about science in VOA Special English.

1 doughty   

adj.勇猛的，坚强的

参考例句：

• Most of successful men have the characteristics of contumacy and doughty.绝大多数成功人士都有共同的特质：脾气倔强，性格刚强。
• The doughty old man battled his illness with fierce determination.坚强的老人用巨大毅力与疾病作斗争。

2 graphic   

adj.生动的，形象的，绘画的，文字的，图表的

参考例句：

• The book gave a graphic description of the war.这本书生动地描述了战争的情况。
• Distinguish important text items in lists with graphic icons.用图标来区分重要的文本项。

3 aspirin   

n.阿司匹林

参考例句：

• The aspirin seems to quiet the headache.阿司匹林似乎使头痛减轻了。
• She went into a chemist's and bought some aspirin.她进了一家药店，买了些阿司匹林。

4 willow   

n.柳树

参考例句：

• The river was sparsely lined with willow trees.河边疏疏落落有几棵柳树。
• The willow's shadow falls on the lake.垂柳的影子倒映在湖面上。

5 swelling   

n.肿胀

参考例句：

• Use ice to reduce the swelling. 用冰敷消肿。
• There is a marked swelling of the lymph nodes. 淋巴结处有明显的肿块。

6 lining   

n.衬里，衬料

参考例句：

• The lining of my coat is torn.我的外套衬里破了。
• Moss makes an attractive lining to wire baskets.用苔藓垫在铁丝篮里很漂亮。

7 intestine   

adj.内部的；国内的；n.肠

参考例句：

• This vitamin is absorbed through the walls of the small intestine.这种维生素通过小肠壁被吸收。
• The service productivity is the function,including external efficiency,intestine efficiency and capacity efficiency.服务业的生产率是一个包含有外部效率、内部效率和能力效率的函数。

8 vessels   

n.血管( vessel的名词复数 )；船；容器；（具有特殊品质或接受特殊品质的）人

参考例句：

• The river is navigable by vessels of up to 90 tons. 90 吨以下的船只可以从这条河通过。 来自《简明英汉词典》
• All modern vessels of any size are fitted with radar installations. 所有现代化船只都有雷达装置。 来自《现代汉英综合大词典》

9 interfere   

v.(in)干涉，干预；(with)妨碍，打扰

参考例句：

• If we interfere, it may do more harm than good.如果我们干预的话，可能弊多利少。
• When others interfere in the affair,it always makes troubles. 别人一卷入这一事件，棘手的事情就来了。

10 interferes   

vi. 妨碍，冲突，干涉

参考例句：

• The noise interferes with my work. 这噪音妨碍我的工作。
• That interferes with my plan. 那干扰了我的计划。

11 enzyme   

n.酵素，酶

参考例句：

• Above a certain temperature,the enzyme molecule will become unfolded.超过一定温度，酶分子将会展开。
• An enzyme that dissolves the fibrin of blood clots.能溶解血凝块中的纤维的酶。

12 clots   

n.凝块( clot的名词复数 )；血块；蠢人；傻瓜v.凝固( clot的第三人称单数 )

参考例句：

• When you cut yourself, blood clots and forms a scab. 你割破了，血会凝固、结痂。 来自《简明英汉词典》
• Milk clots when it turns sour. 奶变酸就凝块。 来自《现代英汉综合大词典》

13 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

14 decided   

adj.决定了的，坚决的；明显的，明确的

参考例句：

• This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
• There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。

15 diabetes   

n.糖尿病

参考例句：

• In case of diabetes, physicians advise against the use of sugar.对于糖尿病患者，医生告诫他们不要吃糖。
• Diabetes is caused by a fault in the insulin production of the body.糖尿病是由体內胰岛素分泌失调引起的。

16 cholesterol   

n.（U）胆固醇

参考例句：

• There is cholesterol in the cell of body.人体细胞里有胆固醇。
• They are determining the serum-protein and cholesterol levels.他们正在测定血清蛋白和胆固醇的浓度。

17 blockage   

n.障碍物；封锁

参考例句：

• The logical treatment is to remove this blockage.合理的治疗方法就是清除堵塞物。
• If the blockage worked,they could retreat with dignity.如果封锁发生作用，他们可以体面地撤退。

18 artery   

n.干线，要道；动脉

参考例句：

• We couldn't feel the changes in the blood pressure within the artery.我们无法感觉到动脉血管内血压的变化。
• The aorta is the largest artery in the body.主动脉是人体中的最大动脉。

19 disorders   

n.混乱( disorder的名词复数 )；凌乱；骚乱；（身心、机能）失调

参考例句：

• Reports of anorexia and other eating disorders are on the increase. 据报告，厌食症和其他饮食方面的功能紊乱发生率正在不断增长。 来自《简明英汉词典》
• The announcement led to violent civil disorders. 这项宣布引起剧烈的骚乱。 来自《简明英汉词典》

20 intestines   

n.肠( intestine的名词复数 )

参考例句：

• Perhaps the most serious problems occur in the stomach and intestines. 最严重的问题或许出现在胃和肠里。 来自辞典例句
• The traps of carnivorous plants function a little like the stomachs and small intestines of animals. 食肉植物的捕蝇器起着动物的胃和小肠的作用。 来自辞典例句

21 hormone   

n.荷尔蒙，激素，内分泌

参考例句：

• Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。
• This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。

22 syndrome   

n.综合病症；并存特性

参考例句：

• The Institute says that an unidentified virus is to blame for the syndrome. 该研究所表示,引起这种综合症的是一种尚未确认的病毒。
• Results indicated that 11 fetuses had Down syndrome. 结果表明有11个胎儿患有唐氏综合征。

23 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。

24 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。

25 weaver   

n.织布工；编织者

参考例句：

• She was a fast weaver and the cloth was very good.她织布织得很快，而且布的质量很好。
• The eager weaver did not notice my confusion.热心的纺织工人没有注意到我的狼狈相。