单项选择题

关于胆道出血的叙述，下列哪项不正确？

A.最常见病因是胆道感染
B.每次出血量200~300ml,很少引起休克
C.周期性出血，1~2周发作1次
D.多采用手术治疗

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An old saying has it that half of all advertising budgets are wasted — the trouble is, no one knows which half. In the internet age, at least in theory, this fraction can be much reduced.By watching what people search for, click on and say online, companies can aim “behavioural” ads at those most likely to buy.In the past couple of weeks a quarrel has illustrated the value to advertisers of such fine- grained information: Should advertisers assume that people are happy to be tracked and sent behavioural ads? Or should they have explicit permission?In December 2010 America’s Federal Trade Commission (FTC) proposed adding a “do not track” (DNT) option to internet browsers, so that users could tell advertisers that they did not want to be followed.Microsoft’s Internet Explorerand Apple’s Safari both offerDNT; Google’s Chrome is due to do so this year. In February the FTC and the Digital Advertising Alliance (DAA) agreed that the industrywould get cracking on responding to DNT requests.On May 31st Microsoft set off the row. It said that Internet Explorer 10, the version due to appear with Windows 8, would have DNT as a default.Advertisers are horrified.Human nature being what it is, most people stick with default settings. Few switch DNT on now, but if tracking is off it will stay off. Bob Liodice, the chief executive of the Association of National Advertisers, says consumers will be worse off if the industry cannot collect information about their preferences. People will not get fewer ads, he says. “They’ll get less meaningful, less targeted ads.”It is not yet clear how advertisers will respond.Getting a DNT signal does not oblige anyone to stop tracking, although some companies have promised to do so. Unable to tell whether someone really objects to behavioural ads or whether they are sticking with Microsoft’s default, some may ignore a DNT signal and press on anyway.Also unclear is why Microsoft has gone it alone.A.fter all, it has an ad business too, which it says will comply with DNT requests, though it is still working out how. If it is trying to upset Google, which relies almost wholly on advertising, it has chosen an indirect method: There is no guarantee that DNT by default will become the norm. DNT does not seem an obviously huge selling point for Windows 8 — though the firm has compared some of its other products favourably with Google’s on that count before. Brendon Lynch, Microsoft’s chief privacy officer, blogged: “We believe consumers should have more control.” Could it really be that simple?Which of the following is true according to Paragraph 6?

A.AdvertisersarewillingtoimplementDNT
B.DNTmaynotserveitsintendedpurpose
C.DNTislosingitspopularityamongconsumers
D.Advertisersareobligedtoofferbehaviouralads

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根据下列内容，回答181-185题。Modem scientists divide the process of dying into two stages--clinical or temporary death andbiological death. Clinical death occurs when the vital organs, such as the heart or lungs, haveceased to function, but have not suffered permanent damage. The organism can still be revived.Biological death occurs when changes in the organism lead to the disintegration of vital ceils andtissues. Death is then irreversible and final.Scientists have been seeking a way to prolong the period of clinical death so that the organismcan be revived before biological death occurs. The best method developed so far involves cooling ofthe organism, combined with narcotic sleep. By slowing down the body's metabolism, cooling de-lays the processes leading to biological death.To illustrate how this works, scientists performed an experiment on a six-year-old femalemonkey called Keta. The scientists put Keta to sleep with a narcotic. Then they surrounded herbody with ice-bags and began checking her body temperature. When it had dropped to 28 degreesthe scientists began draining blood from its body. The monkey's blood pressure decreased and anhour later both the heart and breathing stopped; clinical death set in. For twenty minutes Keta re-mained in this state. Her temperature dropped to 22 degrees. At this point the scientists pumpedblood into its body in the direction of the heart and started artificial breathing. After two minutesthe monkey's heart became active once more. After fifteen minutes, spontaneous breathing began,and after four hours Keta opened her eyes and lifted her head. After six hours, when the scientiststried to give her a penicillin injection, Keta seized the syringe and ran with it around the room.Her behavior differed little from that of a healthy animal.This passage focuses on__________.

A.thedifferencebetweenbiologicalandclinicaldeath
B.theprocessofdying
C.prolongingtheperiodofclinicaldeath
D.thenatureofclinicaldeath