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单选题Medicine Award Kicks off Nobel Prize Announcements Two scientists who have won praise for research into the growth of cancer cells could be candidates for the Nobel Prize in medicine when the 2008 winners are presented on Monday, kicking off six days of Nobel announcements. Australian-born U.S. citizen Elizabeth Blackburn and American Carol Greider have already won a series of medical honors for their enzyme research and experts say they could be among the front-runners for Nobel. Only seven women have won the medicine prize since the first Nobel Prizes were handed out in 1901. The last female winner was U.S. researcher Linda Buck in 2004, who shared the prize with Richard Axel. Among the pair"s possible rivals are Frenchman Pierre Chambon and Americans Ronald Evans and Elwood Jensen, who opened up the field of studying proteins called nuclear hormone receptors. As usual, the award committee is giving no hints about who is in the running before presenting its decision in a news conference at Stockholm"s Karolinska Institute. Alfred Nobel, the Swede who invented dynamite, established the prizes in his will in the categories of medicine, physics, chemistry, literature and peace. The economics prize is technically not a Nobel but a 1968 creation of Sweden"s central bank. Nobel left few instructions on how to select winners, but medicine winners are typically awarded for a specific breakthrough rather than a body of research. Hans Jornvall, secretary of the medicine prize committee, said the 10 million kronor (US $1.3 million) prize encourages groundbreaking research but he did not think winning it was the primary goal for scientists. "Individual researchers probably don"t look at themselves as potential Nobel Prize winners when they"re at work," Jornvall told The Associated Press. "They get their kicks from their research and their interest in how life functions." In 2006, Blackburn, of the University of California, San Francisco, and Greider, of Johns Hopkins University in Baltimore, shared the Lasker prize for basic medical research with Jack Szostak of Harvard Medical School. Their work set the stage for research suggesting that cancer cells use telomerase to sustain their uncontrolled growth.
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单选题 阅读下面的短文,文中有15处空白,每处空白给出了4个选项,请根据短文的内容从4个选项中选择1个最佳答案。 {{B}} Language and Communication{{/B}} A language is a signaling system which operates with symbolic vocal sounds (语声), and which is used by a group of people for the purpose of communication. Let's look at this {{U}}(51) {{/U}} in more detail because it is language, more than anything else, {{U}}(52) {{/U}} distinguishes man from the rest of the physical world. Other animals, it is true, communicate with one another by {{U}}(53) {{/U}} of cries: for example, many birds utter {{U}}(54) {{/U}} calls at the approach of danger; monkeys utter {{U}}(55) {{/U}} cries, such as expressions of anger, fear and pleasure. {{U}}(56) {{/U}} these various means of communication differ in important ways from human language. For instance, animals' cries do not {{U}}(57) {{/U}} thoughts and feelings clearly. This means, basically, that they lack structure. They lack the kind of structure that {{U}}(58) {{/U}} us to divide a human utterance into {{U}}(59) {{/U}}. We can change an utterance by replacing one word in it with {{U}}(60) {{/U}}: a good illustration of this is a soldier who can say, e.g., "tanks approaching from the north", {{U}}(61) {{/U}} who can change one word and say "aircraft approaching from the north" or "tanks approaching from the west"; but a bird has a single alarm cry, {{U}}(62) {{/U}} means "danger!" This is why the number of signals that an animal can make is very limited: the great tit (山雀) is a case {{U}}(63) {{/U}} point; it has about twenty different calls, {{U}}(64) {{/U}} in human language the number of possible utterances is limitless. It also explains why animal cries are very {{U}}(65) {{/U}} in meaning.
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单选题Blend together the eggs, sugar and flour.
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单选题 Relaxation During a state of deep relaxation, several physiological changes take place in the body: the body's oxygen consumption is reduced; the heart heat decreases; muscle tension and sweating ease, and there is decreased sympathetic(交感的) nervous system activity. This restful state not only allows the body to repair and restore itself, but it has a calming effect on the consciousness. How to achieve this state of relaxation, however, is a matter of opinion, and in some medical circles, a matter of controversy(争论). A recent report by Dr. David Holmes of the University of Kansas in the journal "American Psychologist" said that simply sitting in an armchair has just as many beneficial characteristics for the body as meditation(冥想) does. Researchers of other relaxation techniques disagree. These experts believe that more structured techniques, such as meditation, lead to a condition of deep relaxation. The debate goes on, but one thing appears to be clear that the relaxation response can be reached by a number of methods, and the methods themselves are not as important as getting there. One day, one method may work best; on another day, an alternative method may be more appropriate. Once you are aware of all the methods, you can find the one that works best for you. Some of the relaxation techniques are meditation, autoanalysis (自我心理分析) and progressive muscle relaxation. Although these techniques may not, in the end, produce more of a relaxation response than just sitting quietly in a chair, they have the added benefit of structure and discipline, and for these reasons appear to be more effective for most individuals.
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单选题The dentist has decided to {{U}}pull out{{/U}} her bad tooth.
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单选题It"s prudent to start any exercise program gradually at first.
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单选题 下面有.3篇短文,每篇短文后有5道题,每题后面有4个选项。请仔细阅读短文并根据短文回答其后面的问题,从4个选项中选择1个最佳答案。{{B}}第一篇{{/B}} Volunteers are being recruited(征募) to eat raw potatoes in the first human trials of a vaccine grown in genetically engineered vegetables. Researchers in Texas hope that people who eat the potatoes will be protected against common gut(肠,肠子) infections. They believe this technique could prove to be a cost-effective way of growing vaccines in developing countries where such diseases are still killers. Other researchers previously succeeded in using similar techniques to produce potential vaccines Now Hugh Mason and his colleagues at Texas A & M University(得克萨斯农业及机械大学) their plant vaccines on mice and plan to recruit 15 volunteers for a human trial. The team first tested the technique in tobacco plants. They took a strain of Escherichia coli(大肠杆菌) bacteria that causes food poisoning, and identified the part of the poison which binds to its victims gut cells. They then used a modified plant bacterium called Agrobacterium tumefasciens to transfer the segment of DNA which manufactures the binding protein into the tobacco plant. Under normal circumstances, these bacteria transfer packets of DNA into plant cells to force the plant to manufacture the nutrients they need. But in the modified bacteria, the DNA package includes the gene to pro- duce the binding protein. Once the foreign DNA segment was incorporated(结合,合并) into the tobacco's own DNA, the bacteria were killed off with antibiotics. Mason's team then grew these modified tobacco plants and found that they produced the E. coli binding protein. Proof of success came when the tobacco leaves were mashed up(捣碎) and squirted into the stomachs of mice. Mason says that within days the mice started producing specific antibodies to the E. coli poison, but suffered no ill effects from digesting the binding protein. Mason then produced genetically engineered potatoes and fed these to mice, with similar results. Mason's team have used plants to produce vaccines against a number of other infectious agents. For example, they have made a vaccine using a protein from the shell of the Norwalk virus, which causes diarrhoea(腹泻) in children. A third vaccine has also been produced in tobacco using a surface protein from the hepatitis B virus. But Mason says that so far they have only been able to produce small amounts of it in potatoes. Although a vaccine already exists against hepatitis B, a cheaper plant version could make mass immunisation(群众性免疫) possible. One problem with growing potatoes to produce vaccines is that cooking tends to destroy the protein component of the vaccine, so they must be eaten raw. Mason thinks that bananas may be a better option. "One banana could potentially produce a whole host of different vaccines," says Mason.
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单选题We consume a lot more than we are able to produce.
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单选题American Universities and Colleges Higher education is given in colleges and universities. The average course is four years. Students choose their "major" and a number of "electives". Typically, an undergraduate student has to earn a number of "credits", about 120, to receive the Bachelor's degree at the end of four years' study. One credit usually equals one hour of class per week in a single course which lasts 10 to 16 weeks-the length of a "semester". About half of the students are awarded the Bachelor's degree when they leave university. Then the students may go on to graduate school and with a year or two of further study get a master's degree. After another year or two of study and research, they may get a still higher degree as doctor of philosophy. Higher education trains people to become teachers, nurses, engineers, dentists or do other professional work. Lawyers and doctors must go to school longer than four years. Most states have universities that do not charge much money to residents of that state because public taxes help pay the cost of the university. Other universities do not have public money to help them and must charge their students much more to attend. It is common for students to earn money by doing odd jobs during vacations and term-time. Even students from well-off families do part-time jobs in restaurants or supermarkets. Americans do not look down upon anyone engaged in honest work to make money. Part-time jobs can cultivate self-reliance. Most cities have colleges or universities that hold classes at night as well as in the daytime. In this way people who have to work may attend school at night and work for a degree or just take a course in a subject that interests them. Community groups often give courses and lectures, usually about leisure time activities. In many cities, the secondary schools offer classes in adult education.
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单选题The number of the United States citizens who are eligible to vote continues to increase. A. encouraged B. enforced C. expected D. entitled
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单选题He often {{U}}finds fault with{{/U}} my work.
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单选题The planned general strike represents Ua vital/U economic challenge to the government.
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单选题He was elevated to the post of prime minister.
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单选题Herbal medicine (草药) can be used to cure sleeplessness.
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单选题A Udeadly/U disease has affected these animals.
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单选题 A. So far, we have not known exactly yet whether mouth-to-mouth breathing is really useless in CPR. B. Only ten percent of the victims treated with traditional CPR survived with good brain ability. C. CPR keeps blood and oxygen flowing to the heart and brain. D. His studies show that many people do not want to perform mouth-to-mouth breathing on a stranger for fear of getting a disease. E. It said people should increase the number of chest presses from fifteen to thirty for every two breaths given. F. No mouth-to-mouth rescue breaths were given to them.
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单选题Researchers have known for years that animals have a "clock" somewhere in their brains a control-centre that regulates circadian(生物节奏的) rhythms. Circadian rhythms are the body's daily biological cycles, controlling such activities as sleep and wakefulness. In November 1988, neuroscientists at the University of Virginia in Charlotteville reported that the supra chasmatic nucleus(SCN), a small cluster(束)of cells in the middle of the brain that neuroscientists have long suspected of playing a role in daily rhythms, is the long-sought biological clock. The investigators performed a series of tissue-transplant experiments with hamsters (仓鼠). Some of the animals were normal hamsters, which have a circadian cycle of 24 hours; the others were mutant(变异型)hamsters whose cycles were only 20 or 22 hours long. The scientists first removed the SCN from the brans of the hamsters in both groups. They then implanted an SCN from a mutant hamster into the brain of each normal animal, and vice versa. When the hamsters had recovered from their operations, the circadian rhythms of the two groups were reversed. The normal hamsters had a daily cycle of 20 to 22 hours, and the mutants were on a 24-hour cycle. The identification of the internal clock is an important stepping-stone in understanding the basic, automatic mechanisms of brain function. It may also help in finding ways to relieve human sleep disorders.
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单选题Keep on Fighting Turning once again to the question of invasion, I would observe that there has never been a period in all these long centuries of which we boast when an absolute guarantee against invasion, still less against serious raids, could have been given to our people. In the days of Napoleon the same wind which would have carried his transports across the Channel might have driven away the blockading (封锁) fleet. There was always the chance, and it is that chance which has excited and befooled (愚弄的) the imaginations of many continental tyrants. Many are the tales that are told. We are assured that novel methods will be adopted, and when we see the originality of malice (怨恨), the ingenuity of aggression, which our enemy displays, we may certainly prepare ourselves for every kind of novel stratagem (战略) and every kind of brutal and treacherous (奸诈的) maneuver (花招). I think that no idea is so outlandish (古怪的) that it should not be considered and viewed with a searching, but at the same time, I hope, with a steady eye. We must never forget the solid assurances of sea power and those which belong to air power if it can be locally exercised. I have, myself, full confidence that if all do their duty, if nothing is neglected, and if the best arrangements are made, as they are being made, we shall prove ourselves once again able to defend our island home, to ride out the storm of war, and to outlive the menace (威胁) of tyranny, if necessary for years, if necessary alone. At any rate, that is what we are going to try to do. This is the resolve of his Majesty"s government—every man of them. This is the will of parliament and the nation. The British Empire and the French republic, linked together in their cause and in their need, will defend to the death their native soil, aiding each other like good comrades to the utmost of their strength. Even though large tracts of Europe and many old and famous states have fallen or may fall into the grip of the Gestapo and all the odious (可憎的) apparatus of Nazi rule, we shall not flag (变弱) or fail. We shall go on to the end, we shall fight in France, we shall fight on the seas and oceans, we shall fight with growing confidence and growing strength in the air, we shall defend our island, whatever the cost might be, we shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills, we shall never surrender, and even if, which I do not for a moment believe, this island or a large part of it were subjugated (征服) and starving, then our empire beyond the seas, armed and guarded by the British fleet, would carry on the struggle, until, in God"s good time, the new world, with its power and might, steps forth to the rescue and the liberation of the old.
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单选题These are our motives for doing it.
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单选题One Good Reason to Let Smallpox Live It's now a fair bet that we will never see the total extinction of the smallpox virus. The idea was to cap the glorious achievement of 1980, when smallpox was eradicated in the wild, by destroying the killer virus in the last two labs that are supposed to have it-one in the US and one in Russia. If smallpox had truly gone from the planet, what point was there in keeping these reserves? (51) reality, of course, it was naive to (52) that everyone would let (53) of such a potent potential weapon. 1 Undoubtedly several nations still have (54) vials. (55) the last "official" stocks of live virus bred mistrust of the US and Russia, (56) no obvious gain. Now American researchers have (57) an animal model of the human disease, opening the (58) for tests on new treatments and vaccines. So one again there's a good reason to (59) the virus-just in (60) the disease puts in a reappearance. How do we (61) with the mistrust of the US and Russia? (62) Keep the virus (63) international auspices in a well-guarded UN laboratory that's open to all countries. The US will object, of course, just as it rejects a multilateral approach to just about everything. But it doesn't (64) the idea is wrong. If the virus (65) useful, the let's make it the servant of all humanity—not just a part of it.
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