Artificial hearts have long been the stuff of science fiction. In "Robocop", snazzy cardiac devices are made by Yamaha and Jense

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问题     Artificial hearts have long been the stuff of science fiction. In "Robocop", snazzy cardiac devices are made by Yamaha and Jensen, and in "Star Trek", Jean-Luc Picard, captain of the Enterprise, has one implanted in the year 2328. In the present day, however, their history has been more chequered. The first serious attempt to build one happened in the 1980s, when Jarvik-7, made by Robert Jarvik, a surgeon at the University of Utah, captured the world’s attention. But Jarvik-7 was a complicated affair that needed to be connected via tubes to machines outside the body. The patient could not go home, nor even turn around in bed. Scientists have tried many other designs, but all were seen as temporary expedients intended to tide a patient over until the real thing became available from a human donor.
    That may be about to change. This week, America’s Food and Drug Administration gave its approval to a new type of artificial heart made by Abiomed, a firm based near Boston. The agency granted a "humanitarian device exemption" , a restricted form of approval that will allow doctors to implant the new device in people whose hearts are about to fail but who cannot, for reasons such as intolerance of the immunosuppressive drugs needed to stop rejection, receive a transplant. Such people have a life expectancy of less than a month, but a dozen similarly hopeless patients implanted with Abiomed’s heart survived for about five months.
    Unlike Dr. Jarvik’s device, this newfangled bundle of titanium and polyurethane aims to set the patient free. An electric motor which revolves up to 10,000 times a minute pushes an incompressible fluid around the Abiomed heart, and that fluid, in turn, pushes the blood—first to the lungs to be oxygenated, and then around the body. Power is supplied by an electric current generated in a pack outside the body. This induces current in the motor inside the heart. All diagnostics are done remotely, using radio signals. There are no tubes or wires coming out of the patient.
    The charger is usually plugged into the mains, but if armed with a battery it can be carried around for hours in a vest or backpack, thus allowing the patient to roam freely. Most strikingly, the device’s internal battery can last half an hour before it needs recharging. That allows someone time to take a shower or even go for a quick swim without having to wear the charger.
    Abiomed’s chairman, Michael Minogue, does not claim that his firm’s product will displace human transplants. Even so, the firm has big ambitions. It is already developing a new version that will be 30% smaller (meaning more women can use it) and will last for five years. That should be ready by 2008—320 years earlier than the writers of "Star Trek" predicted.
It can be concluded from the second paragraph that

选项 A、the regulatory approval is limited with respect to the scope of application.
B、the life expectancy will not be improved compared with that indicated by the current record.
C、America’s Food and Drug Administration gave its approval to a new type of artificial heart.
D、Doctors will implant the new device in patients whose hearts are about to fail.

答案A

解析 这是一道细节分析题。本题的答案信息来源在第二段的第二、三句,尤其是第三句中的“a restricted form of approval”(一种局限性的准许形式),暗示“相关准许是在一定范围内的准许,是一种受到某种限制的准许,并非绝对的准许”。由此可以推断本题的答案应该是选项A。考生在阅读时要对原文中的修饰限定性词语认真对待和理解。
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