14 科技新闻摘要（三）
DATE=5-1-01
TITLE=SCIENCE IN THE NEWS #2122 - Digest
BYLINE=Staff
VOICE ONE:
This is Bob Doughty.
VOICE TWO:
And this is Sarah Long with Science in the News, a VOA Special English program about recent developments in science. Today, we tell about a new (1) genetic treatment for Alzheimer's disease. We tell about the discovery of stem cells in fat. And we tell about the （2）decrease in the number of giant pandas at the Wolong Nature （3）Reserve in China.
((THEME))
VOICE ONE:
Doctors have placed genetically changed cells into the brain of a woman with Alzheimer's disease. They operated on the sixty-year-old woman in a hospital in California. The patient was showing early signs of Alzheimer's. This （4）experimental operation was an effort to （5）control or stop the （6）destruction of brain cells caused by the disease.
Alzheimer's disease affects millions of people around the world. It damages and destroys cells in many areas of the brain. It slowly robs its (7) victims of intelligence and the ability to remember. As it progresses people can no longer care for themselves. There is no cure.
VOICE TWO:
Mark Tuszynski of the University of California at San Diego developed the new treatment. He says it is the first genetic （8） treatment for a disease that destroys brain tissue. Doctor Tuszynski developed the treatment to increase the effectiveness of a brain chemical called acetylcholine. This chemical is known to fight the brain damage caused by Alzheimer's disease.
Doctors took healthy skin cells from the patient. They added specially treated genes to the cells. These cells were designed to produce a protein called （9）nerve growth factor. Nerve growth factor helps normal brain cells survive and grow. Doctors then placed the genetically changed cells into five areas deep in the right side of the patient's brain. The cells are meant to release nerve growth factor into （10）surrounding areas of the brain.
VOICE ONE:
Hoi Sang U led the team of doctors who operated on the patient. She was treated to prevent pain during the eleven-hour （11）operation. This permitted her to stay awake so the doctors could observe her reactions as they operated.
Doctor Tuszynski says it may be years before they know if the genetic treatment helped this patient. He says placing the genetically changed cells into a damaged brain probably cannot cure the disease. But he says it may help delay the progress of the disease and improve the （12） quality of life. Doctors say they will perform the gene （13） therapy treatment on seven more patients if the first patient shows no bad effects.
VOICE TWO:
Doctor Tuszynski performed research on rats and monkeys for years before testing his treatment on a person. His studies in animals showed the nerve growth factor could help keep some special brain cells healthy. These cholinergic cells are among several kinds of brain cells that Alzheimer's disease destroys. These brain cells are especially important because they help people learn and remember. Cholinergic cells contain the (14) acetylcholine that helps protect normal brain cells.
Doctor Tuszynski received permission from two government agencies to treat Alzheimer's disease patients. The Food and Drug Administration and a committee of the National Institutes of Health approved his research in Nineteen-Ninety-Nine. The F-D-A still must say the process is safe for humans before permitting its effectiveness to be measured.
VOICE ONE:
Some scientists fear the treatment is not safe. They say genetically changed cells might poison the brain or produce a （15）tumor. Or the treatment might cause bleeding in the brain. Earlier tests of nerve growth factor in humans reportedly have caused such problems.
However, these processes were not done by （16）operation. Doctor Tuszynski says he believes his studies have shown this treatment will not produce harmful results. He believes the genetic treatment for Alzheimer's disease can succeed.
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VOICE TWO:
You are listening to the Special English program SCIENCE IN THE NEWS on VOA. This is Sarah Long with Bob Doughty in Washington.
((MUSIC BRIDGE))
American medical researchers say they have discovered stem cells in human fat for the first time. Stem cells are able to develop into other kinds of cells, including nerve, bone and muscle cells.
Scientists have been studying the use of stem cells to treat and possibly cure many diseases. These stem cells have the power to grow into new heart muscle for people with heart disease. Or the stem cells can become new insulin-producing cells for people suffering （17）diabetes.
Researchers have collected stem cells from the brain, bones and (18) fetal tissue from unborn babies. Getting these stem cells for research purposes is difficult. And many people are opposed to using fetal tissue for research. The new discovery means that it might be easier to get stem cells for research and treatment of diseases.
VOICE ONE:
Researchers from the University of California at Los Angeles and the University of Pittsburgh carried out the study. The researchers took fat from the stomachs and legs of healthy adults in an operation known as liposuction. About six- hundred- thousand such operations are done in the United States every year. People choose to have liposuction to remove unwanted body fat.
The researchers treated the fat with a substance that separated out the stem cells. They found that about two- hundred grams of fat could produce as many as fifty- million to one- hundred- million stem-like cells. Then they used different chemicals to change those cells into bone cells, (19) cartilage cells and muscle cells.
VOICE TWO:
This is the first study to show that a person's own stem cells in fat might someday be used to treat disease or repair injured body parts. This would solve the problems of （20）rejection by the body because no foreign tissue would be used. Scientists are working to confirm the findings of this experiment. They are testing the stem cells in animals. If this is successful, researchers say human testing could begin in about five years.
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VOICE ONE:
A new report says human activities are harming the Wolong Nature Reserve, China's largest protected area for giant pandas. The report says the environment in the nature reserve is being destroyed quicker than in other parts of China that are not protected. This is causing a decrease in the panda population in the nature reserve. Giant pandas are becoming increasingly rare in the wild. Only about one- thousand of the animals live in the mountains of southwestern China.
VOICE TWO:
Chinese officials established Wolong Nature Reserve in Nineteen-Seventy-Five. It covers two- hundred-t housand hectares of land in Sichuan Province. However, the number of pandas in Wolong has decreased since the reserve was created. The research team says there were one- hundred- forty- five pandas in the reserve in Nineteen-Seventy-Four. Twelve years later, the panda population fell to seventy-two. The team says the number probably is even smaller today.
Giant pandas live in mountain areas where there are plenty of forests. They eat mainly (21) bamboo plants. The researchers compared the rates of change in Wolong's forests and environment before and after the reserve opened. They examined satellite images taken since Nineteen-Sixty-Five.
VOICE ONE:
The researchers found that humans have taken control of large parts of Wolong. Jianguo Liu of Michigan State University led the study. He says human settlements have grown in the reserve, mainly because it has so many visitors. The human population has increased by seventy percent since the reserve was created. The people are cutting more trees for fuel and other uses. This has destroyed areas where pandas live.
Mister Liu's team says the best hope for Wolong is to improve education for the young people who live there. Then they can get jobs and move to other parts of China.
A panda expert at the World Wildlife Fund says China has more than thirty other protected areas for giant pandas. Most of them are not threatened by human activities. And she says panda protection is becoming very important in China.
((THEME))
VOICE TWO:
This SCIENCE IN THE NEWS program was written by Jerilyn Watson, Nancy Steinbach and George Grow. It was produced by George Grow. This is Sarah Long.
VOICE ONE:
And this is Bob Doughty. Join us again next week for more news about science in Special English on the Voice of America.
注释：
（1） genetic[ ????????? ]adj.遗传的, 起源的
（2） decrease[???????????]n.减少, 减少之量v.减少
（3） reserve[?????????]n.储备(物), 储藏量v.储备, 保存
（4） experimental [ ?????????????? ]adj.实验的, 根据实验的
（5） control[????????]n.控制, 支配v.控制, 支配
（6） destruction[ ??????????? ]n.破坏, 毁灭
（7） victim[?????????]n.受害人, 牺牲者
（8） treatment[ ???????????]n.待遇, 对待
（9） nerve[ ?????]n.神经, 胆量v.鼓起勇气
（10） surrounding[ ?????????? ]n.围绕物, 环境adj.周围的
（11） operation[ ????????????]n.运转, 操作
（12） quality[ ???????? ]n.质量, 品质
（13） therapy[ ??????? ]n.治疗
（14） acetylcholine[?????????????????]n.[化]乙酰胆碱
（15） tumor[ ??????? ]n.瘤
（16） operation[ ??????????? ]n.运转, 操作
（17） diabetes[ ?????????????????????]n.[医] 糖尿病, 多尿症
（18） fetal[ ???????]adj.胎儿的, 胎的
（19） cartilage[ ?????????? ]n.[解剖]软骨
（20） rejection[??????????? ]n.拒绝
（21） bamboo[???????? ]n.竹子
15 科技新闻摘要（四）
DATE=5-8-01
TITLE=SCIENCE IN THE NEWS #2123 - Digest
BYLINE=Staff
VOICE ONE:
This is Bob Doughty.
VOICE TWO:
And this is Sarah Long with Science in the News, a VOA Special English program about recent developments in science. Today, we tell about a new drug to treat cancer of the blood. We tell about a new study of the care of young children. And we tell about a lake in Africa that is （1）shrinking.
((THEME))
VOICE ONE:
A new drug appears to produce good results as a (2) treatment for one kind of （3）leukemia or cancer of the blood. In a recent study, the medicine helped patients' blood become normal in fifty-three out of fifty-four cases. Fifty-one of the patients still are doing well after taking the medicine for about one year. Cancer experts say this success rate is very unusual. However, researchers note that it is too early to know how the drug affects patients' (4) survival over long periods of time.
Brian Druker of Oregon Health Sciences University led two studies of the drug. The studies were published in the New England Journal of Medicine.
VOICE TWO:
The new drug is called Gleevec. Recent tests show that Gleevec helps people who suffer from chronic （5）myeloid leukemia. There are several different kinds of leukemia. All of them affect the body's (6) production of blood cells. Chronic myeloid leukemia causes the body to produce unhealthy white blood cells. After a period of time, the body produces more unhealthy cells than healthy ones.
The drug works by (7)blocking the action of an （8）enzyme that does not work correctly within the body. The enzyme is said to be (9) defective.
A (10) chromosome lacking several genes causes the enzyme to be produced. The enzyme makes a (11) protein that causes defective white blood cells to be produced (12) uncontrollably. Gleevec appears to stop this process by blocking the action of the defective enzyme.
VOICE ONE:
Gleevec also appears to fight different kinds of (13) cancer as well. Some researchers have had good results using the drug against cancer of the stomach and （14）intestines. Glivec is also being tested on some lung cancers and brain cancer. However, scientists say more research is necessary.
Scientists say the drug may be important because it targets the cause of the disease without damaging other cells. They say the drug is also important because the goal of cancer research is to identify the differences between cancer cells and normal cells.
Gleevec is made by the Swiss company Novartis. Novartis has asked the United States Food and Drug Administration to approve Gleevec for treatment of chronic myeloid leukemia. The drug company also permits some people to use the drug now through a special experimental program.
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VOICE TWO:
You are listening to the Special English program SCIENCE IN THE NEWS on VOA. This is Sarah Long with Bob Doughty in Washington.
VOICE TWO:
An American study has linked aggression in children to the amount of time they spend away from their mothers.
The study compared young children who stayed with their mothers to children who were cared for by other people. It found that those who spent long periods away from their mothers were more likely to be (15) aggressive toward other children. They were also more likely to (16) disobey orders.
Study organizers say the findings were true, even when they considered different kinds of childcare or the family's (17) financial situation.
The ten-year study is widely considered the most complete (18) investigation yet of childcare in the United States. The National Institute of Child Health and Human Development provided financial support for the study. The (19) agency is part of the National (20) Institutes of Health.
VOICE ONE:
Childcare is a major issue in the United States and other countries. The Children's Defense Fund is a group concerned with improving the (21) quality of childcare. It (22) reports that thirteen- million young American children are cared for by someone other than their parents until they are old enough to begin school. Children usually begin school at the age of five or six.
The Children's (23) Defense Fund reports that almost thirty percent of young children are in child care centers. Such centers usually care for thirteen or more children while their parents are at work. About fifteen percent of young boys and girls are cared for by someone in a private home. Five percent stay in their own home with someone other than a parent or family member.
About twenty-five percent of young children stay with a family member. The remaining twenty- four percent are cared for by one or both of their parents.
VOICE TWO:
The new study involved more than one- thousand- three- hundred children in ten American cities. The children spent an (24) average of twenty-six hours a week away from their mothers in childcare.
Researchers found that seventeen percent of the children who spent more than thirty hours a week in child care showed behavior problems by the time they were ready to start school. Only six percent of those who spent less than ten hours a week in childcare had the same problems.
Jay Belsky of the University of London was one of the lead investigators in the study. He said children who spent more than thirty hours a week in childcare were more demanding and (25) aggressive. He said they also were more likely to fight with other children, do bad things to other children and talk too much.
VOICE ONE:
The study had other interesting findings. The boys and girls who spent more time in childcare were found to be more fearful and sad compared to other children. However, these differences disappeared by the time the children were ready to begin school.
There was also good news for boys and girls who spent long periods in child care centers during their early years. The study found they were more likely to have better (26) language skills and better short-term memory.
VOICE TWO:
Doctor Belsky warned parents not to overreact to the study's findings. He said the findings do not mean that children in childcare are a danger to society. He suggested that parents could increase the time they spend with their children.
Some experts on work and family life question the findings. They say many American mothers have to work. They say childcare is the only choice for some families if they want to avoid being poor. Other experts say the study suggests the need to improve the quality of childcare in the United States.
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VOICE ONE:
Scientists say there has been a severe (27) decrease in the amount of water in Lake Chad in northern Africa in the last thirty years. They report that nature and humans share equal blame for this loss. In 1963, the fresh-water lake covered twenty-five-thousand-square kilometers. Now the lake is only about five percent of that size. It measures only about 1,300 square kilometers in the dry season.
Four nations surround Lake Chad. People in (28) Niger, Nigeria, Chad, and (29) Cameroon use it for water and fish.
VOICE TWO:
Michael Coe and Jonathan Foley are water experts at the University of Wisconsin in Madison. They reported about Lake Chad in the Journal of (30) Geophysical Research. They say the area has suffered from a lack of heavy rain for more than thirty years. This has forced people to build systems to carry water to dry land. These irrigation systems further decrease the lake.
Mister Coe says Lake Chad will be only a small body of water in the future. He says people still can get water from the lake to drink and for crops. But he says the lake will no longer provide a healthy environment for fish and plant life.
VOICE ONE:
The researchers used a computer to study what caused the water loss. They say major irrigation systems were built in the Nineteen-Eighties. The systems took water from two rivers that flow into Lake Chad. The Chari and Logone rivers carry most of the water that enters the lake.
The study showed the increased (31) irrigation reduced the flow in the two rivers. Climate changes also were responsible for the reduction. Today the flow of the two rivers has been reduced by almost seventy-five percent.
Scientists say the problem is expected to worsen in the coming years as the population and demand for water continue to increase.
((THEME))
VOICE TWO:
This SCIENCE IN THE NEWS program was written by Mario Ritter, George Grow and Jerilyn Watson. It was produced by George Grow. This is Sarah Long.
VOICE ONE:
And this is Bob Doughty. Join us again next week for more news about science in Special English on the Voice of America.
注释：
(1) shrink[?????? ]v.收缩, (使)皱缩, 缩短
(2) treatment[ ???????????]n.待遇, 对待, 处理, 治疗
(3) leukemia[ ??????????? ]n.白血病
(4) survival[ ????????? ]n.生存, 幸存
(5) myeloid[??????????? ]a.骨髓的
(6) production[ ?????????? ]n.生产, 产品
(7) blocking[ ????????]v.舞台场面设计,舞台调度
(8) Enzyme [???????] n. [生化] 酶
(9) defective[ ????????? ]adj.有缺陷的
(10) chromosome[ ????????????]n.[生物]染色体
(11) protein[ ????????? ]n.[生化]蛋白质
(12) uncontrollable[?????????????????]adj.无法控制的
(13) cancer[??????? ]n.癌, 毒瘤
(14) intestine[?????????? ]adj.内部的, 国内的n.[解, 动]肠
(15) aggressive[ ?????????]adj.好斗的, 敢做敢为的
(16) disobey[ ??????????]v.违反, 不服从
(17) financial[??????????????????]adj.财政的, 金融的
(18) investigation[???????????????? ]n.调查, 研究
(19) agency[ ??????????]n.代理处, 行销处
(20) institute[ ??????????? ]n.学会, 学院
(21) quality[ ?????????]n.质量, 品质
(22) report[???????? ]n.报告, 传说v.报导, 汇报
(23) defense[???????? ]n.(美国)国防部, 防卫v.谋划抵御
(24) average[ ???????? ]adj.一般的, 通常的v.平均v.买进, 卖出
(25) aggressive[??????????]adj.好斗的, 敢做敢为的
(26) language[ ????????? ]n.语言
(27) decrease[???????????]n.减少, 减少之量v.减少
(28) Niger[ ????????]n.尼日尔(非洲中西部国家)
(29) Cameroon[ ????????? ]n.喀麦隆(非洲西部国家)
(30) geophysical[???????????????]adj.地球物理学的
(31) irrigation[ ??????????? ]n.灌溉, 冲洗
