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Nội dung: <blockquote data-quote="Butchi" data-source="post: 92104" data-attributes="member: 7">Transgenic Monkeys Produced in JapanHướng dẫn: Nghe audio, theo dõi và phán đoán từ cần điền vào chỗ trống. Bôi đen các chỗ trống để xem đáp án.[MP3]https://server1.vnkienthuc.com/files/3/Media/20090623a.mp3[/MP3]This is SCIENCE IN THE NEWS, a program in VOA Special English.  I'm Bob Doughty. And I'm Shirley Griffith. This  week, we will tell about a study involving monkeys and a gene from  jellyfish.  We will tell about an agreement to ban nine dangerous  chemicals.  We will also report on problems linked to cigarette smoking  and alcoholic drinks. (MUSIC) Scientists in Japan say they  have produced [A]monkeys[/A] with a gene that gives the skin of the animals an [A]unusual look[/A].  The skin is said to look bright green under ultraviolet  lighting. The scientists say the monkeys represent an important  step in how [A]researchers [/A]study human disease.  These marmosets are the  first fully transgenic primates.  Primates are the biological group of  animals that includes monkeys and apes.  An animal that has received  foreign genetic material is considered transgenic. For almost  thirty years, researchers have used [A]transgenic mice[/A] to carry out  biomedical research.  To produce these animals, researchers inject  fertilized mice eggs with foreign genes, and then place them in the  uterus of a female mouse.  The specially chosen genes are then expressed  in some of the [A]mouse's babies[/A]. Transgenic mice help researchers  study the [A]appearance[/A] and treatment of human diseases.  But mice are not  as helpful as primates are for studying the behavior of human diseases. Scientists  at Japan's Central Institute for Experimental Animals led the study  that made the [A]transgenic marmosets[/A].  The scientists say they injected a  green glowing protein found in jellyfish into fertilized marmoset eggs.   They chose this gene because it is easy to see with a fluorescent  light. Four of the five marmosets born as part of the experiment  carried the foreign gene in several kinds of tissue.  The fifth only  carried the green protein in its placenta tissue at birth.  Two of the  animals later showed the foreign gene in their [A]reproductive cells[/A].  This  means they would pass on the gene for the green protein to their young. Later,  a male transgenic marmoset reproduced and passed on the green gene to a  baby.  This is the first time scientists have successfully passed on a  foreign gene to a future generation.  And, it means that transgenic  marmosets can be produced from breeding instead of by the [A]lengthy  process[/A] of injecting fertilized eggs. The scientists say the  marmosets could one day be easily produced for medical research.  They  could be used to study conditions like Parkinson's disease and Lou  Gehrig's disease.  A report about the [A]experiment [/A]was published last  month in Nature magazine. (MUSIC) Officials from more than  one hundred sixty governments have agreed to ban production of nine of  the world's most [A]dangerous chemicals[/A].  The agreement was announced last  month at a United Nations conference in Switzerland. The chemicals  are joining twelve other [A]substances[/A] that are already banned under a  treaty known as the Stockholm Convention.  The treaty was signed in two  thousand one. The Stockholm Convention governs some kinds of [A]industrial chemicals[/A] and pesticides -- products meant to kill insects.   These substances can damage the human nervous system and natural  defenses against disease.  They have also been linked to cancer,  reproductive disorders and interfere with [A]normal child development[/A].  The  substances can also kill people. Donald Cooper is Executive  Secretary of the Stockholm Convention.  He says the substances are  especially dangerous because they travel through the air and stay in the  atmosphere, soil and water.  It takes many years for them to weaken.   Mr. Cooper says the substances build up in the cells of plants, animals  and [A]human beings[/A]. One of the newly banned chemicals is  perflurooctane sulfonic acid, or PFOS.  It is found in electrical parts  and [A]fire-fighting products[/A].  Another banned chemical is the pesticide  Lindane.  It is used in some areas as a treatment for head lice. The  governments at the U.N. conference also reached a decision on another  pesticide, DDT.  They said they want DDT banned, but recognize that some  countries use it to protect people from diseases like [A]malaria[/A].  The  governments said they will consider a plan that supports safer,  effective choices to DDT.  And, they hope to ban its use by two thousand  ten. (MUSIC) Chronic obstructive pulmonary disease, also  known as C.O.P.D., blocks airflow through the lungs.  It makes breathing  difficult.  The leading cause is [A]cigarette smoking[/A].  America's National  Institutes of Health says the damage to the lungs cannot be repaired  and there is no cure. Dawn DeMeo is an assistant professor at Harvard Medical School in Massachusetts. DAWN DeMEO: "By two thousand and twenty, C.O.P.D. will likely be the third leading cause of death across the world." C.O.P.D.  is a new name for emphysema and [A]chronic bronchitis[/A].  These are the two  most common forms of the disease.  Many people with C.O.P.D. have both  of them. Doctor DeMeo wrote about a study by a team from Harvard's  Brigham and Women's Hospital and the University of Bergen in Norway.   The study adds to findings that women may be more at risk than men for  the [A]damaging effects[/A] of smoking. The team examined results from a  Norwegian study of more than nine hundred people with C.O.P.D.   Inga-Cecilie Soerheim also wrote about the team's findings.  She says  they show that women suffered the same severity of C.O.P.D. as men.   But, the female smokers were younger and had smoked a lot less. The  team also looked at two groups among the people in the study.  These  were people under the age of sixty and those who had smoked for less  than twenty years.  In both cases, women had more severe C.O.P.D. and a  greater loss of [A]lung function[/A] than men. The study was presented last month to the American Thoracic Society. Doctor  Soerheim says there are several possible explanations why women may be  more at risk from the effects of cigarette smoke than men.  Women have  smaller airways, she says, so each cigarette may do more harm.  Also,  there are differences between males and females in the way the body [A]processes[/A] cigarette smoke.  And, she says, genes and hormones could also  play an important part. (MUSIC) Finally, a listener in  Taiwan wrote to ask why his face [A]turns red [/A]when he drinks alcohol.  This  effect called facial flushing is a common reaction to alcohol among  East Asians.  It affects an estimated thirty-six percent of Japanese,  Chinese and Koreans. For many people, even a little alcohol can  cause[A] unpleasant effects[/A].  Most commonly, their face, neck and sometimes  their whole body turns red.  People might also feel sick to their  stomach and lightheaded.  They might experience a burning sensation,  increased heart rate, shortness of breath and headaches. The cause  is a genetic difference that some people are born with.  It prevents  their bodies from processing alcohol the way other people do.  But the  effects might be more serious than just a red face.  Researchers have  warned of a link between this condition and an increased risk of [A]cancer[/A]  of the esophagus from drinking alcohol. A report about facial  flushing appeared recently in PLoS Medicine, a publication of the Public  Library of Science.  The report says the more alcohol that persons with  this deficiency drink, the greater their risk.  It estimates that at  least five hundred forty million people have the deficiency. Esophageal  cancer is one of the [A]deadliest cancers[/A].  It can be treated when found  early.  But once it grows the chances of survival drop sharply. Philip  Brooks is a researcher at America's National Institute on Alcohol Abuse  and Alcoholism.  Doctor Brooks says it is important to educate people  about the link between the alcohol flushing effect and [A]esophageal  cancer.[/A]  He says doctors should ask East Asian patients about their  experiences with facial flushing after drinking alcohol.  Those with a  history of it should be advised to limit their alcohol use.  They should  also be warned that cigarette smoking works with the alcohol in a way  that further increases the risk of esophageal cancer.This  SCIENCE IN THE NEWS was written by Lawan Davis, Dana Demange and June  Simms.  Our producer was Brianna Blake.  I'm Shirley Griffith. And I'm  Bob Doughty.  Join us again next week for more news about science in  Special English on the Voice of America. </blockquote>

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