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.
"Star Trek" is mentioned in the text in order to

选项 A、depict the long history of artificial hearts in science fiction.
B、enumerate artificial hearts of all sorts on sale.
C、provide background for the discussion of artificial hearts.
D、emphasize the great efforts made by Yamaha and Jensen in the development of artificial hearts.

答案C

解析 这是一道中心主旨类题目。本文的中心主旨段(即为中心主旨句所在段落)是原文的第二段。原文的第一段是为第二段的到来进行的铺垫。故本题的正确选项应该是C(为对人造心脏的讨论提供背景)。要注意:阅读中的例子是为作者观点服务的,而不是单纯为了交代例子中的事情,段落中的例子一般是为了说明段落主旨,而文章开头的例子一般是为了引出或者论证全文主旨。因此,考生在阅读时要注意揣摩全文主旨和作者意图,找好主旨句和主旨段。
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