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SCIENCE IN THE NEWS - Ginkgo as Memory Aid Disputed / New Fi

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SCIENCE IN THE NEWS - September 17, 2002: Ginkgo as Memory Aid Disputed / New Findings About
Deadly Skin Cancer / Hair and Sex Lives of Lions


VOICE ONE:
This is Sarah Long.
VOICE TWO:
And this is Steve Ember with Science in the News, a VOA Special English program about recent developments


in science. Today, we tell about a new study of a product people take to improve their memory. We tell some
new information about lions. We tell about an unusual side effect of an anti-cancer drug. And we tell some new
research about a deadly form of skin cancer.

((THEME)
)
VOICE ONE:
Memory problems are a sign of old age. A number of products claim to have the ability to improve memory and


other mental activities. Many older adults around the world take a substance called ginkgo in an effort to treat the
problem. Now, a new study is disputing the effectiveness of ginkgo.


Ginkgo is an herb, the part of a plant valued for its medical uses. It comes from the
leaves of the ginkgo biloba tree. Ginkgo is an anti-oxidant, much like vitamins C
and E. Scientists believe anti-oxidants protect the body from damage caused by
harmful oxygen particles called free radicals1.

VOICE TWO:

Millions of Americans take ginkgo as a way to improve their memory. They spend
hundreds of millions of dollars on ginkgo products. Doctors in Germany commonly
suggest ginkgo for treating mental problems.

Scientists from Williams College in Williamstown, Massachusetts organized the new ginkgo study. It involved
more than two-hundred people over sixty years of age. All of the people were in good mental health.

For six weeks, half the group took forty milligrams of ginkgo three times a day. The other half took an inactive
substance or placebo2. The people did not know which substance they were taking.

VOICE ONE:

The Williams College researchers questioned a close friend of each person about any changes in mental ability.
No differences were observed. Everyone in the study also took a series of tests designed to show their mental
abilities including memory before, during and after the study. The scientists found no measurable improvement in
memory or any other mental ability.

The Journal of the American Medical Association reported the findings. The National Institute on Aging
provided money for the study.

VOICE TWO:

In recent years, the American government has approved such studies to examine claims made by producers of
herbal products. The Food and Drug Administration sets rules for medicines sold in the United States, but not for
herbal products.

Makers3 of ginkgo were quick to dispute the findings. Boehringer Ingelheim Pharmaceuticals4 made the ginkgo


products used in the study. A company official said that other studies have found that ginkgo improved people’s
memory. An industry trade group added that larger studies are necessary.
((MUSIC BRIDGE)
)


VOICE ONE:
The lion is perhaps the most famous member of the cat family. Lions are well known for their power and beauty.
Adult male lions are the only cats with manes. This long, thick hair covers the animal’s head and neck.


For years, biologists have wondered why lions have manes or what purpose they
serve. One suggestion is that the thick hair protects a lion’s neck during fights with
other males. Another idea is that the mane is a sign of the male’s physical
condition. This idea says the hair frightens other males and helps females choose
successful mates.

VOICE TWO:

Now, a new American study suggests that manes strongly influence the sex life of
lions. Two University of Minnesota scientists found that female lions in Tanzania
like males with dark manes. Science magazine reported their findings.

Peyton West and Craig Packer studied lions in Tanzania’s world famous Serengeti National Park. They set up
life-size models of lions near where the wild animals live. The models of the lions had different kinds of manes.
Then, they waited to see how the lions would react to the models.

VOICE ONE:

The scientists say the results were clear. Male lions were not afraid to move toward the model lions with short
and light-colored manes. The females were less concerned about hair length. However, they avoided the model
lions with lighter5 manes. Ninety percent of the time, the females moved toward the model lions with dark hair.

Mizz West said the females seemed to be reacting to the physical condition of the males. She said lions with dark
manes usually have higher levels of the male hormone6 testosterone. She notes that such lions are more aggressive
fighters. They win fights more often. Her studies show that male lions with dark manes are more likely to recover
from wounds. They also are able to frighten other lions and defend their families.

((MUSIC BRIDGE))

VOICE TWO:

A drug normally used to treat cancer has been found to have a surprising side effect. It appears to restore color to
gray hair in some people.

Doctors from the Victor Segalen University in Bordeaux, France were testing the drug,
called Gleevec. Last year, American officials approved Gleevec for treatment of chronic7
myeloid leukemia, a rare form of blood cancer.

The French doctors gave the drug to one-hundred-thirty-three leukemia patients. The
drug darkened the hair of nine patients who had gray hair. The darkening effect began
two to fourteen months after the patients began taking the drug.

VOICE ONE:

One doctor said the effect may have been found in even more patients. It was difficult to identify the true
numbers because some patients had used hair coloring products to darken their hair.

The New England Journal of Medicine published the findings. Gleevec has strong side effects. It can damage the
liver and blood. So doctors say the drug should not be used as a hair-coloring product. But scientists have begun


Would he have tried it?

to study the unusual side effect.
((MUSIC BRIDGE)
)
VOICE TWO:
Scientists have discovered a genetic9 change that can cause malignant10 melanoma, the most serious kind of skin


cancer. The cancer spreads through the body. Malignant melanoma kills almost forty-thousand people around the


world each year.

The new research was reported in the publication Nature. The work was done by
medical scientists involved in the Cancer Genome Project at the Wellcome Trust
Sanger Institute in Cambridge, England. The aim of the Cancer Genome Project is
to find which of the thirty-thousand human genes11 are involved in cancer.

VOICE ONE:


Genes contain material called D-N-A. The order of the D-N-A in a gene8 is
represented by a series of letters. A change, or mutation12, happens when the order of the letters changes.
Mutations happen in two ways. Chemicals, radiation or viruses can damage D-N-A. Damage also can result from
mistakes before cells divide.


Most of these mutations are harmless. However, sometimes a mutation in a gene will cause cells to act in an
unusual way. For example, a changed gene will cause a cell to divide when it should stop dividing. Or the cell
will move away from its normal place and into another organ. This is how cancer begins. Experts say it takes
about twenty-five years from the time of the first gene mutation until a cancerous growth appears in adults.


VOICE TWO:


Cancer Genome Project researchers have been examining human genes to find the abnormal13 genes that cause
cells to become cancerous. The change that causes malignant melanoma is the first one they have found. It is in
the gene called B-R-A-F, one of a group of genes that must all be turned on for a cell to grow and divide.


Scientists say when a gene causes a cell to grow and divide it is “turned on.

Normally, it then “turns off”
and stops the cell from dividing any more. The Genome Project scientists found that the mutation makes the gene
stay turned on all the time. It causes the cells to divide and never stop. This leads to cancer.


The researchers say the finding could lead to effective drugs to treat melanoma. They have already started
searching for drugs to make the gene turn off and stop the growth of the cancer. But they also say that people
should try to prevent malignant melanoma from developing by staying out of the sun as much as possible.


((THEME)
)


VOICE ONE:


This SCIENCE IN THE NEWS program was written by George Grow and Nancy Steinbach. It was produced by
Cynthia Kirk. This is Sarah Long.


VOICE TWO:


And this is Steve Ember. Join us again next week for more news about science in Special English on the Voice of
America.

 

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点击收听单词发音收听单词发音  

1 radicals 5c853925d2a610c29b107b916c89076e     
n.激进分子( radical的名词复数 );根基;基本原理;[数学]根数
参考例句:
  • Some militant leaders want to merge with white radicals. 一些好斗的领导人要和白人中的激进派联合。 来自《简明英汉词典》
  • The worry is that the radicals will grow more intransigent. 现在人们担忧激进分子会变得更加不妥协。 来自辞典例句
2 placebo placebo     
n.安慰剂;宽慰话
参考例句:
  • The placebo has been found to work with a lot of different cases.人们已发现安慰剂能在很多不同的病例中发挥作用。
  • The placebo effect refers to all the observable behaviors caused by placebo.安慰剂效应是指由安慰剂所引起的可观察的行为。
3 makers 22a4efff03ac42c1785d09a48313d352     
n.制造者,制造商(maker的复数形式)
参考例句:
  • The makers of the product assured us that there had been no sacrifice of quality. 这一产品的制造商向我们保证说他们没有牺牲质量。
  • The makers are about to launch out a new product. 制造商们马上要生产一种新产品。 来自《简明英汉词典》
4 pharmaceuticals be065c8a4af3a2d925d11969faac34cf     
n.医药品;药物( pharmaceutical的名词复数 )
参考例句:
  • the development of new pharmaceuticals 新药的开发
  • The companies are pouring trillions of yen into biotechnology research,especially for pharmaceuticals and new seeds. 这些公司将大量资金投入生物工艺学研究,尤其是药品和新种子方面。 来自《简明英汉词典》
5 lighter 5pPzPR     
n.打火机,点火器;驳船;v.用驳船运送;light的比较级
参考例句:
  • The portrait was touched up so as to make it lighter.这张画经过润色,色调明朗了一些。
  • The lighter works off the car battery.引燃器利用汽车蓄电池打火。
6 hormone uyky3     
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。
7 chronic BO9zl     
adj.(疾病)长期未愈的,慢性的;极坏的
参考例句:
  • Famine differs from chronic malnutrition.饥荒不同于慢性营养不良。
  • Chronic poisoning may lead to death from inanition.慢性中毒也可能由虚弱导致死亡。
8 gene WgKxx     
n.遗传因子,基因
参考例句:
  • A single gene may have many effects.单一基因可能具有很多种效应。
  • The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。
9 genetic PgIxp     
adj.遗传的,遗传学的
参考例句:
  • It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
  • Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。
10 malignant Z89zY     
adj.恶性的,致命的;恶意的,恶毒的
参考例句:
  • Alexander got a malignant slander.亚历山大受到恶意的诽谤。
  • He started to his feet with a malignant glance at Winston.他爬了起来,不高兴地看了温斯顿一眼。
11 genes 01914f8eac35d7e14afa065217edd8c0     
n.基因( gene的名词复数 )
参考例句:
  • You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因,所以能够活得很长。 来自《简明英汉词典》
  • Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪
12 mutation t1PyM     
n.变化,变异,转变
参考例句:
  • People who have this mutation need less sleep than others.有这种突变的人需要的睡眠比其他人少。
  • So far the discussion has centered entirely around mutation in the strict sense.到目前为止,严格来讲,讨论完全集中于围绕突变问题上。
13 abnormal UIvy2     
adj.反常的,不正常的,不规则的
参考例句:
  • This warm weather is abnormal for February.二月里这种温暖的天气不太正常。
  • That is simply abnormal.那简直是反常的。

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