首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Many people today are worried about bird flu. They are afraid that it will pass from birds to humans and that thousands of peopl
Many people today are worried about bird flu. They are afraid that it will pass from birds to humans and that thousands of peopl
admin
2022-10-28
29
问题
Many people today are worried about bird flu. They are afraid that it will pass from birds to humans and that thousands of people will die in a pandemic. In 1918 a flu virus killed about 50 million people around the world. The virus was called Spanish influenza (or Spanish flu, for short) because Spanish newspapers first described the disease. Now, after nine years of work, scientists in an American laboratory in Atlanta, Georgia, have produced a copy of the Spanish flu virus. They are also going to publish the genetic sequence of the virus on the Internet and some experts are afraid that other laboratories could copy the virus.
Scientists have copied the virus because they want to understand why the 1918 Spanish flu pandemic killed so many people. In a report in the journal Science, Dr. Jeffery Taubenberger and a team of scientists in the USA show that the copied virus is extremely powerful. The scientists injected the virus into mice and the mice began to lose weight very quickly. They lost 13% of their weight in two days and all of the mice died within six days.
"I didn’t expect it to be as lethal as it was, " Dr. Terrence Tumpey, one of the scientists in the team, told the journal Nature. In another experiment, they injected more mice with a normal type of flu. The mice lost weight at first but then they got better and did not die. The experiments showed that the mice with the Spanish flu virus had 39,000 times more flu virus in their bodies than the second group of mice.
The scientists who copied the virus say their work has already provided important information about the virus and helps to explain why it is so lethal. But other experts are worried that the virus could escape from the laboratory. " Some people will think that they have really created a biological weapon," said Professor Ronald Atlas of the University of Louisville in Kentucky. " I am even more worried now than I was before about the possibility of a flu pandemic. The 1918 flu pandemic started with bird flu and that might happen again today with Asian bird flu."
Some scientists are worried about the publication of the genetic sequence on the Internet. They are afraid that biologists could copy the virus using the information on the Internet. This could be very dangerous.
It took a long time to copy the virus. Scientists used material taken from the lungs of people who died from the flu virus in 1918. In a second report in Nature, Taubenberger and his colleagues analyzed the genetic make-up of the virus. They were surprised to find that it was completely different from all the normal human flu viruses. This probably means that Spanish flu jumped from birds to humans and did not mix with a human virus first. This is very worrying for scientists because in the past everyone believed that a pandemic was only possible if a bird flu virus mixed with a human flu virus.
Taubenberger says it is very important to know what changes in the virus caused the 1918 Spanish flu virus. This will help scientists to work out which viruses might cause a pandemic. The H5N1 bird flu in Asia is already changing and it could infect humans, he said.
Viruses have escaped from high-security labs before. The SARS virus escaped at least twice, once in Taiwan and once in Singapore. But some scientists believe a pandemic will not happen even if the virus escapes, because most people are naturally immune and there are now a lot of drugs which protect people from flu.
What is H5N1?
选项
答案
A bird flu virus.
解析
根据第七段最后一句可知,H5N1是亚洲的一种禽流感病毒,正在发生变异,有可能感染人类。
转载请注明原文地址:https://jikaoti.com/ti/FSCiFFFM
本试题收录于:
C类竞赛(非英语专业本科)题库大学生英语竞赛(NECCS)分类
0
C类竞赛(非英语专业本科)
大学生英语竞赛(NECCS)
相关试题推荐
ThefamilyisthecenterofmosttraditionalAsians’lives.Manypeopleworryabouttheirfamilies’welfare,reputation,andhon
Mostworthwhilecareersrequiresomekindofspecializedtraining.Ideally,therefore,thechoiceofan【C1】________shouldbemad
Mostworthwhilecareersrequiresomekindofspecializedtraining.Ideally,therefore,thechoiceofan【C1】________shouldbemad
Generallyspeaking,aBritishiswidelyregardedasaquiet,shyandconservativepersonwhois【C1】________onlyamongthosewith
Canada’spremiers(theleadersofprovincialgovernment),iftheyhaveanybreathleftaftercomplainingaboutOttawaattheirl
Psychologistsusedtobelievethatgreaterprejudiceamongolderadultswasduetothefactthatolderpeoplegrewupinlesseg
"Forestsarethelungsofourland,"saidFranklinDelanoRoosevelt.Twentyyearsago,theworld’slungswerediseased.Roughly
Thehumanspecieshasincreaseditslifespanby________.
Inperiodofthesummerholidaystherewillbearevisedschedule(修改过的时刻表)ofser-vicesforthestudents.Changesfordining-ro
A:Excuseme,Iamareporterfromastudentmagazine.【D1】________B:Sure,Please.A:Wheredoyoucomefrom?B:IamfromGerm
随机试题
关于工程质量有缺陷时的说法正确的是()。
投资收益率是指投资方案建成投产并达到设计生产能力后一个正常生产年份的()的比率。
下列可以作为个人汽车贷款担保方式的有()。
我国采用班级授课制最早是在()年的京师同文馆。
某村村委会,根据村情民意,决定发展食用菊花种植、绿色蔬菜生产、生态家禽养殖等特色农业,带领村民致富。为确保特色农业顺利发展,村委会动员村里的能人带头示范。通过这些能人的辛勤努力和村委会的积极服务,这些示范户当年都取得了较高的收益。村民们纷纷效仿,很快在村里
给定资料1.中国人讲究礼尚往来,逢年过节来往走动,互赠礼物,互祝安康,也是美好情谊的表达。特别是在结婚这样的喜事上更是讲究礼尚往来。操办婚礼无可厚非,但是动辄十几万甚至几十万的彩礼、几百几千的份子钱,亲朋好友连吃多天的婚宴酒席等大操大办、铺张
教学
深度为5的完全二叉树的结点数不可能是
—Readthearticlebelowaboutcost.—Choosethebestwordtofilleachgap,fromA,B,CorD.—Foreachquestion19—33,markon
()收益人()到期()海运提单()信用证
最新回复
(
0
)