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Text 2 Judging from recent surveys, most experts in sleep behavior agree that there is virtually an epidemic of sleepiness in the nation. "I can’t think of a single study that hasn’t found Americans getting less sleep than they ought to," says Dr David. Even people who think they are sleeping enough would probably be better off with more rest. The beginning of our sleep-deficit crisis can be traced to the invention of the light bulb a century ago. From diary entries and other personal accounts from the 18th and 19th centuries, sleep scientists have reached the conclusion that the average person used to sleep about 9. 5 hours a night. "The best sleep habits once were forced on us, when we had nothing to do in the evening down on the farm, and it was dark." By the 1950s and 1960s, that sleep schedule had been reduced dramatically, to between 7.5 and 8 hours, and most people had to wake to an alarm clock. "People cheat on their sleep, and they don’t even realize they’re doing it," says Dr David. "They think they’re okay because they can get by on 6.5 hours, when they really need 7.5, 8 hours or even more to feel ideally vigorous." Perhaps the most merciless rubber of sleep, researchers say, is the complexity of the day. When ever pressures from work, family, friends and community mount, many people consider sleep the least expensive item on his programme. "In our society, you’re considered dynamic if you say you only need 5.5 hours’ sleep. If you’ve got to get 8.5 hours, people think you lack drive and ambition." To determine the consequences of sleep deficit, researchers have put subjects through a set of psychological and performance tests requiring them, for instance, to add columns of numbers or recall a passage read to them only minutes earlier. "We’ve found that if you’re in sleep deficit, performance suffers," says Dr David. "Short-term memory is weakened, as are abilities to make decisions and to concentrate." The underlined word "subjects"(Line 1, Para. 4) refers to ______.
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Text 3 Thousands of years ago man used handy rocks for his surgical operations. Later he used sharp bone or horn, metal knives and more recently, rubber and plastic and that was where we stuck, in surgical instrument terms, for many years. In the 1960s a new tool was developed, one which was, first of all, to be of great practical use to the armed forces and industry, but which was also, in time, to revolutionize the art and science of surgery. The tool is the laser and it is being used by more and more surgeons all over the world, for a very large number of different complaints. The word "laser" means: light amplification by stimulated emission of radiation. As we all know, light is hot, any source of light -- from the sun itself down to a humble match burning -- will give warmth. But light is usually spread out over a wide area. The light in a laser beam, however, is concentrated. This means that a light with no more power than that produced by an ordinary electric light bulb becomes intensely strong as it is concentrated to a pinpoint-sized beam. Experiments with these pinpoint beams showed researchers that different energy sources produce beams that have a particular effect on certain living cells. It is now possible for eye surgeons to operate on the back of the human eye without harming the front of the eye, simply by passing a laser beam right through the eyeball. No knives, no stitches, no unwanted damage -- a true surgical wonder. Operations which once left patients exhausted and in need of long period of recovery time now leave them feeling relaxed and comfortable. So much more difficult operations can now be tried. The rapid development of laser techniques in the past ten years has made it clear that the future is likely to be very exciting. Perhaps some cancers will be treated with laser in a way that makes surgery not only safer but also more effective. Altogether, tomorrow may see more and more information coming to light on the diseases which can be treated medically. What do we find after the development of the laser in the 1960s
25，“少阴病，下利清谷，里寒外热，手足厥逆，脉微欲绝，______，______，或腹痛，或干呕，或咽痛，或利止脉不出者，______。”
阅读下面一段文字，完成下列问题。①生物体都具有感觉器官，无论是感知物理信息抑或检测化学信息的这些自然感测器，都是生物体藉以获得生存必需信息的良好帮手。然而人要获得客观世界的大量信息，光凭人类自身的感觉器官是远远满足不了的，必须借助人造的各类感测器。②科学家们首先想到的是存在于生物体内的2000多种不同的酶。由于在人体生命活动中担任催化剂作用的酶具有严密的对象选择性，即某一种酶只促成对应的某种对象的化学反应，科学家们就巧妙地设计出各种带不同酶的生物类化学感测器。为了克服酶会溶于水而不能反复使用的技术难题，他们又将酶涂布在高分子膜上，然后将这种带酶的膜放进所测试的采样中，催化受质(待测的特定化学物质)的化学反应。在膜附近产生或消耗的其他化学物质，通过膜上带有的碳电极测定化学物质的浓度变化，就能间接地计算出原受质的浓度。这样，只要使用不同的酶，便可制成测定各种不同化学物质的生物感测器了。③这种生物感测器是高技术的结晶。它利用了先进的印刷和半导体加工技术。先在基板上印刷碳电极，再印刷附着特定酶的膜，之后裹上多孔的高分子膜，类似集成电路的制作。一般是在同一基片上制成大量感测元件，只要将它们切开，就能同时制成多枚生物感测器。④如今科学家已不满足于上述利用物质电特性制成的生物感测器，他们又投入以物质的光特性为基础的光纤传感类的新型生物感测器的研制，并将其广泛应用于各个领域。 第三段的“这种生物感测器”指什么正确的一项是（）。
阅读下面的文章，完成下列问题。文艺不单是作者人格的表现，也是一般人生世相的返照。培养人格是一套工夫，对于一般人生世相积蓄丰富而正确的学识经验又是另一套工夫。这可以分两层说。一是读书。从前中国文人以能熔经铸史为贵。韩愈在《进学解》里发挥这个意思，最为详尽。读书功用在储知蓄理，扩充眼界改变气质。读的范围愈广，知识愈丰富审辩愈精当胸襟也愈恢阔。在近代，一个文人不但要博习本国古典，还要涉猎近代各种学问，否则见解难免偏蔽。这事固然很难。我们第一要精选，不要浪费精力于无用之书。第二要持恒，日积月累涓涓终成江河。第三要有哲学的高瞻远瞩，科学地客观剖析，否则食而不化，学问反而足以梏没性灵。其次是实地观察体验。这对于文艺创作或比读书还更重要。从前中国文人喜游名山大川，一则增长阅历，一则增加自然界瑰奇壮丽之气与幽深玄渺之趣。其实这种“气”与“趣”不只在自然中可以见出，在一般的人生世相中也可得到。许多著名的悲喜剧与近代小说所表现的学超精神气魄正不让于名山大川。观察体验的最大功用还不仅在此，尤其在洞达人情物理。文学超现实而不能脱离现实，它所创造的世界尽管有时是理想的，却不能不有现实的真实性。近代写实主义者主张文学须有“凭证”，就因为这个道理。你想写某一种社会或某一种人物，你必须对于那种社会人物的外在生活与内心生活都有彻底的了解，这非多观察体验不可。要观察得正确，体验得深刻，你最好投身他们中间，和他们过同样的生活。你过的生活愈丰富，对于人性的了解愈深刻，你的作品就愈有真实性，不至于如雾里看花。 不能体现“实地观察体验”对于文艺创作或比读书还更重要的一项是（）。
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