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
Shortages of flu vaccine are nothing new in America, but this year’ s is a whopper. Until last week, it appeared that 100 millio
Shortages of flu vaccine are nothing new in America, but this year’ s is a whopper. Until last week, it appeared that 100 millio
admin
2018-03-16
28
问题
Shortages of flu vaccine are nothing new in America, but this year’ s is a whopper. Until last week, it appeared that 100 million Americans would have access to flu shots this fall. Then British authorities, concerned about quality-control problems at a production plant in Liverpool, barred all further shipments by the Chiron Corp. Overnight, the U. S. vaccine supply dwindled by nearly half and federal health officials found themselves making an unusual plea. Instead of beseeching us all to get vaccinated, they’ re now urging most healthy people between the ages of 2 and 64 not to. "This reemphasizes the fragility of our vaccine supply, " says Dr. Martin Myers of the National Network for Immunization Information, " and the lack of redundancy in our system. "
Why is such a basic health service so easily knocked out? Mainly because private companies have had little incentive to pursue it. To create a single dose of flu vaccine, a manufacturer has to grow live virus in a 2-week-old fertilized chicken egg, then crack the egg, harvest the virus and extract the proteins used to provoke an immune response. Profit margins are narrow, demand is fickle and, because each year’ s flu virus is different, any leftover vaccine goes to waste. As a result, the United States now has only two major suppliers(Chiron and Aventis Pasteur)—and when one of them runs into trouble, there isn’ t much the other can do about it. " A vaccine maker can’ t just call up and order 40 million more fertilized eggs, " says Manon Cox, of Connecticut-based Protein Sciences Corp. "There’ s a whole industry that’ s scheduled to produce a certain number of eggs at a certain time. "
Sleeker technologies are now in the works, and experts are hoping that this year’ s fiasco will speed the pace of innovation. The main challenge is to shift production from eggs into cell cultures—a medium already used to make most other vaccines. Flu vaccines are harder than most to produce this way, but several biotech companies are now pursuing this strategy, and one culture-based product(Solvay Pharmaceuticals’ Invivac)has been cleared for marketing in Europe.
For Americans, the immediate challenge is to make the most of a limited supply. The government estimates that 95 million people still qualify for shots under the voluntary restrictions announced last week. That’ s nearly twice the number of doses that clinics will have on hand, but only 60 million Americans seek out shots in a normal year. In fact, many experts are hoping the shortage will serve as an awareness campaign—encouraging the people who really need a flu shot to get one.
The word "cleared"(Line 4, Paragraph 3)might mean______.
选项
A、permitted
B、removed
C、proved
D、produced
答案
A
解析
在第三段最后一句“…one culture-based product has been cleared for marketing in Europe.”里出现了“cleared”一词。根据下文中“marketing”和读者有关药品上市前应该得到批准的常识,可以判断出,该词在本句中的意思是“得到官方的批准”。因此正确答案为A。
转载请注明原文地址:https://jikaoti.com/ti/InIsFFFM
本试题收录于:
公共英语五级笔试题库公共英语(PETS)分类
0
公共英语五级笔试
公共英语(PETS)
相关试题推荐
WhatiswrongwiththeAmericandiet?
______almosthadnointertribalwarfare?______,______havesomeoftheirpeoplelivinginCanada?
Detailsoftheprivatelifeofanastronautarehardtocomeby,becausetheyare______.Toaudience,thetypicalAmericanastr
Howmanylanguagesareusedthroughouttheworldtoday?
BillGatesistherichestprivatecitizenintheworld.Thereisnothinghecan’t(31).Everymorning,whenhisalarmclockgoes
Theauthorpointsoutatthebeginningthat______.Accordingtothepassage,allofthefollowingmayaffectaperson’shandedn
Theenvironmentiseverythingthatsurroundsusandcanaffectusinsomeway.
Theenvironmentiseverythingthatsurroundsusandcanaffectusinsomeway.
Psychologistssaytherearetwodifferentkindsofloneliness.
Psychologistssaytherearetwodifferentkindsofloneliness.
随机试题
垂直牙体牙根裂常发生在使用桩核修复的牙齿。使用哪一类桩核修复后,垂直牙体牙根裂的可能性最大A.有螺纹的圆柱形桩核B.有螺纹的圆锥形桩核C.无螺纹的圆柱形桩核D.无螺纹的圆锥形桩核E.以上无差异
小儿右髋部摔伤,首选的X线检查方法是
蜂蜜丸中蜂蜜加热105~115℃,含水量达到17%~20%属于()。
下列工序质量控制的方法,属于工序质量预控的有()。
下列关于股票内在价值与价格关系的表述中,错误的是( )。
某投资中心投资额为1000000元,企业加权平均的最低投资报酬率为18%,剩余收益为200000元,则该中心的投资报酬率为20%。()
假设某计算机有1MB的内存,并按字节编址,为了能存取其中的内容,其地址寄存器至少需要(9)位。为使4字节组成的字能从存储器中一次读出,要求存放在存储器中的字边界对齐,一个字的地址码应(10)。若存储周期为200ns,且每个周期访问4B,则该存储器的带宽为
直接转移指令执行时,是将指令中的地址送入()。
在基于ARM微处理器为核心的硬件平台上,开发其Linux环境下的应用程序expl.c。若需要编译后生成expl.c对应的汇编程序,应使用的命令是()。
AccordingtoAmericanlaw,ifsomeoneisaccusedofacrime,heisconsidered【B1】______untilthecourtprovesthepersonisguil
最新回复
(
0
)