单选题Physical Exercise Declaring that physical exercise is one of the most powerful medicines to help improve our quality of life is not an exaggeration. The World Health Organization expressed the same view in its 2002 World Heath Report, emphasizing that the damage produced by lack of physical activity was equal to the strong probability of serious illness such as heart disease and even some kinds of cancer. Those who have embraced an active lifestyle for years are familiar with the sort of physical and psychological benefits that come from exercise. Nevertheless a lot of people would never think of physical activity as a way of feeling better, simply because they don"t think they are in need of it, or because they are lazy or maintain that they haven"t got enough time. There are many positive effects that result from physical exercise and they are not only concerned with the physical aspects but also psychological and social ones. Beginning with the physical benefits, physical activity improves the life of the heart, burns off fat, lowers high blood pressure, makes tissues more resistant, and increases muscle flexibility and joint mobility. On a psychological level, physical activity helps reduce anxiety and stress by causing tension to disappear and by encouraging us to have a better sense of ourselves through listening to our bodies during movement. Lastly, seeing ourselves in better health is advantageous socially. The sense of satisfaction thus obtained will result in an increase of self-respect and serf-confidence in terms of our ability to interact with others. The benefits linked to exercise have also not gone unnoticed in the business world, with more and more companies setting up gyms on-site. Employees" improved health translates into better performance and reduced costs as well as an increase in people"s satisfaction in the workplace. Physical activity is recommended for all age groups, including children. It is an important growth factor in a child"s education. And for the elderly? There is no doubt that regular physical activity allows greater efficiency in daily life as well as creating more basic independence day by day, including the possibility of keeping in touch with others and not feeling isolated.

单选题Black Americans are more likely to die of cancer than

单选题Nightingale's parents did not approve of her decision

单选题Unidentified Flying Object Unidentified Flying Object (UFO) is any object or light, reportedly sighted in the sky, that cannot be immediately explained by the observer. Sightings of unusual flying objects date back to ancient times, but UFOs (sometimes called flying saucers) became widely discussed only after the first widely publicized U. S sighting in 1947. Many thousands of such observations have since been reported worldwide. At least 90 percent of UFO sightings can be identified as conventional objects, although time—consuming investigations are often necessary for such identification. The objects most often mistaken for UFOs are bright planets and stars, aircraft, birds, balloons, kites, aorial flares, peculiar clouds, meteors, and satellites. The remaining sightings most likely can be attributed to other mistaken sightings or to inaccurate reporting, tricks, or delusions, although to disprove all claims made about UFOs is impossible. From 1947 to 1969 the U. S. Force investigated UFOs as a possible threat to national security. A total of 12,618 reports were received, of which 701 reports, or 5.6 percent, were listed as unexplained. The air force concluded that "no UFO reported, investigated, and evaluated by the Air Force has ever given any indication of threat to our national security". Since 1969 no agency of the U.S. government has had any active program of UFO investigation. Some persons, however, believe that UFOs are extraterrestrial spacecraft, even though no scientifically valid evidence supports that belief. The possibility of extraterrestrial civilizations is not the stumbling block; most scientists grant that intelligent life may well exist elsewhere in the universe. A fully convincing UFO photograph has yet to be taken, however, and the scientific method requires that highly speculative explanations should not be adopted unless all of the more ordinary explanations can be ruled out. UFO enthusiasts persist, however, and some persons even claim to have been captured and taken aboard UFOs. No one has produced scientifically acceptable proof of these claims. Behavioral scientist Carl Sagan once proposed that "certain psychological needs are met by belief in superior beings from other worlds. /

单选题Henry cannot resist the {{U}}lure{{/U}} of drugs

单选题There was ample time to get to the airport.

单选题He spoke in a {{U}}temperate{{/U}} manner, not favoring either side especially.

单选题That performance was （pretty） impressive.

单选题These factors interact intimately and cannot be separated.

单选题Please watch the milk carefully; I don't want it to {{U}}boil{{/U}} over.

下面的短文后有2项测试任务：(1)第23～26题要求从所给的6个选项中为第2～?段名其中4段选择1个最佳标题；(2)第27～30题要求从所给的6个选项中为每个句子确定1个最佳选项。 {{B}}Screen Test{{/B}}1. Every year millions of women are screened with X-rays to pick up signs of breast cancer. If this happens early enough, the disease can often be. treated successfully. According to a survey published last year, 21 countries have screening programmes. Nine of them, including Australia, Canada, the US and Spain, screen women under 50.2. But the medical benefits of screening these younger women are controversial, partly because the radiation brings a small risk of inducing cancer. Also, younger women must be given higher doses of X-rays because their breast tissue is denser.3. Researchers at the Polytechnic University of Valencia analysed the effect of screening more than 160,000 women at 11 local clinics. After estimating the women's cumulative dose of radiation, they used two models to calculate the number of extra cancers this would cause.4. The mathematical model recommended by Britain's National Radiological Protection Board (NRPB) predicted that the screening programme would cause 36 cancers per 100,000 women, 18 of them fatal. The model preferred by the UN Scientific Committee on the Effects of Atomic Radiation led to a lower figure of 20 cancers.5. The researchers argue that the level of radiation-induced cancers is "not very significant" compared to the far larger number of cancers that are discovered and treated. The Valencia programme, they say, detects between 300 and 450 cases of breast cancer in every 100,000 women screened.6. But they point out that the risk of women contracting cancer from radiation could be reduced by between 40 and 80 percent if screening began at 50 instead of 45, because they would be exposed to less radiation. The results of their study, they suggest, could help "optimise the technique" for breast cancer screening.7. "There is a trade-off between the diagnostic benefits of breast screening and its risks," admits Michael Clark of the NRPB. But he warns that the study should be interpreted with caution. "On the basis of the current data, for every 10 cancers successfully detected and prevented there is a risk of causing one later in life. That's why radiation exposure should be minimized in any screening programme."

Timothy Stow of Inver Grove Heights, Minn. worked hard, exercised often and thought he got plenty of sleep. Yet he never felt rested. The 20-year-old salesman dozed off during meetings and had four car accidents after falling asleep at the wheel. {{U}}(46) {{/U}} {{U}} (47) {{/U}}Electrodes affixed from head to toe kept track of all activity in his brain, heart, eyes, faces, arms and legs. {{U}} (48) {{/U}} When he slept, the soft tissue at the back of his throat, near the base of his tongue, collapsed against itself, blocking air intake. Each time his breath was cut off—about 100 times an hour—his brain would alert him to awaken and breathe. He never woke to full consciousness, but neither did he fall into a deep, restful sleep. Sleep apnea afflicts millions of Americans, typically middle-aged, overweight men. The problem begins gradually with loud and prolonged snoring. {{U}}(49) {{/U}} In severe cases, the victim spends most of his sleep time not breathing. Doctors at the center gave Stow a Continuous Positive Airway Pressure (CPAP) device. {{U}}(50) {{/U}} A. Now when he retires, he straps over his nose a soft rubber mask connected to a small unit that supplies just enough air pressure to hold his airway open so he can breathe continuously. B. Finally his doctor sent him to the Minnesota Regional Sleep Disorders Center in Minneapolis. C. Later, at the end of each run of snores comes a brief breath-holding spell. D. Doctors soon realized that Stow was a victim of sleep apnea. E. Many people have chronic sleep problems. F. Placed in a quiet room, Stow went to sleep at his usual time.

Some people can quite accurately time the end of their night's sleep at will, without using an alarm clock, demonstrating that it is possible to voluntarily control a state of consciousness that is characterized by a loss of volition and attentional guidance. Here we show that the expectation that sleep will come to an end at a certain time induces a marked increase in the concentration of the hormone adrenocorticotriopin(促肾上腺皮质激素) in the blood one hour before waking. The regulation of adrenocorticotropin release during nocturnal sleep is therefore not confined to daily rhythms; {{U}}(46) {{/U}} {{U}}(47) {{/U}} Normally, the release of adrenocorticotropin and cortisol(皮质醇)increases during late stages of sleeping, reaching a daily maximum at the time of spontaneous waking. Adrenocorticotropin and cortisol are also released from the pituitary-adrenal system in a major adaptive response to stress, and are secreted in anticipation of stressful events. We investigated whether the increase in the secretion of pituitary-adrenal hormones during the late stages of sleeping in part reflects anticipation of the 'stress' of the waking phase. {{U}}(48) {{/U}} We made recordings of electroencephalogram, electrooculogram and electromyogram throughout the night, and took blood samples every 15 minutes to determine plasma concentrations of adrenocorticortropin and cortisol. Lights were turned off at midnight, after subjects had been told they would be woken at either 6:00 ('short sleep', on one night) or 9:00('long sleep', on the other two nights). On one of the long-sleep nights they were woken at 9:00 as they expected, but on the other night they were instead woken at 6:00 ('surprise')under the pretence of a technical problem. {{U}}(49) {{/U}} We interviewed the volunteers at the end of the experiments, and found that all but one of the subjects had expected to be woken up at the specified time. The order of the three experimental nights was balanced across subjects, with five subjects starting with short sleep, five with long sleep, and five with the surprise condition. The increase in adrenocorticotropin release before the expected time of waking indicates that anticipation, which is generally considered to be a unique characteristic of the regulation of conscious action, pervades sleep {{U}}(50) {{/U}} The regulation of adrenocorticotropin release points to a mechanism that quickly adjusts endocrine activity to sharp changes in the duration. A. The regulation of sleep termination has been thought to embedded in a daily rhythm controlling in paralleling the release of pituitary and adrenal hormones. B. Fifteen healthy volunteers with regular sleep-wake rhythms were studied during three nights. C. It also reflects a preparatory process in anticipation of the end of sleep D. After being woken, subjects stayed in bed for another three hours E. The anticipatory adrenocorticotropin increase may also facilitate spontaneous waking F. About 10 million Americans consult doctors sleep problems each year

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}}Can Loud Music Cause Hearing Impairment (损伤)?{{/B}} Have you ever gone to a concert and realized that your seats were right next to the booming speakers? Are you guilty______(51) turning up the volume on your portable cassette or CD player to drown out the whining (哭哭啼啼) of your little brother? Sometimes it's difficult to avoid loud music or noises, but they can be bad news because loud noises can______(52) temporary or permanent hearing loss. Extremely loud music and noises that go on for long periods of______(53) are common causes of deafness. If a noise is so loud that you have to shout to make yourself______(54), there is a______(55) that the mechanism inside your ear can be injured. Temporary hearing loss can happen after you've been______(56) to loud noise for only 15 minutes. If you have temporary hearing loss, you won't be able to hear as______(57) as you normally can, and you may have tinnitus (耳鸣), which is a fancy word for ringing in the ears. Your ears can feel "full", too.______(58), these things usually go away and your hearing soon returns to normal. Permanent hearing loss can happen when someone is exposed to loud noise ______(59) and over. Construction workers and people who work in factories must ______(60) ear protectors because the equipment they use can be extremely loud. But even some lawn mowers (割草机) and power tools can permanently______(61) a person's ability to hear high-pitched noises and can also give him permanent tinnitus. Listening to extremely loud music over and over can also have the same effect on a person's______(62). And using headphones on a portable cassette or CD player can be dangerous______(63) if the volume is too high and the headphones are used a lot, the noise can damage the ears. The best way to avoid hearing loss is to wear ear protectors when working with machinery and earplugs when going to a______(64). Headphones are OK to wear when you're listening to music; just be sure the volume isn't too high, and give them a rest______(65) once in a while.

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}} Eat for a Good and Healthful Life{{/B}} Food{{U}} (1) {{/U}}us alive. It is our sustenance and our pleasure. But recently, research has shown that the eating habits of the average Americans may be dangerous to future health. The foods Americans now choose are oftentimes too{{U}} (2) {{/U}}in calories and fats, so this article reports a new study: Diet and Health, Implications for Reducing Chronic Disease Risk. The study, conducted{{U}} (3) {{/U}}the National Research Council's Committee on Diet and Health,{{U}} (4) {{/U}}that balancing nutrition, calories and activity is key{{U}} (5) {{/U}}enjoying a long and healthful life. The report recommends that most Americans increase{{U}} (6) {{/U}}activity to a moderate level and make changes in food{{U}} (7) {{/U}}and calories intake to maintain ideal weight. Most of us-- even those of us at ideal weight--need to eat{{U}} (8) {{/U}}fat so that no more than 30% of our dally calories will come from fat. That means cutting{{U}} (9) {{/U}}on red meat and whole milk dairy products.{{U}} (10) {{/U}}, eat fish, chicken without skin, lean meats, and low-fat and no-fat dairy products. The report of the Committee on Diet and Health recommends we eat five or more 1/2-cup servings of vegetables and fruits{{U}} (11) {{/U}}-- especially green and yellow vegetables and citrus fruits. Eating more fruits and vegetables doesn't have to mean increased calories intake. Many plant foods are nutrient-rich: they provide many vitamins and minerals for very few{{U}} (12) {{/U}}. Nutrient-rich foods are particularly important for Americans{{U}} (13) {{/U}}age 50. As we{{U}} (14) {{/U}}, we need to eat less because our bodies need{{U}} (15) {{/U}}calories to function properly. But we still need full measures of vitamins and minerals to release the energy in our foods and make us feel strong and healthy.

Can New Doctors Be Harmflul to Your Health? Between the nerves, the unfamiliarity and the urge to impress, few people do themselves justice on the first day of a new job. When it comes to doctors starting out in emergency medicine, though, are patients' lives being put at risk? According to research from Imperial College London, the death rate among patients admitted to English hospitals on the first Wednesday in August -the day, traditionally, that newly graduated doctors take up their posts--was, on average, 6% higher than for those admitted the last Wednesday in July. An influx of new medical staff, in other words, just might be very, very bad for your health. In the university' s study (the biggest of its kind so far), published Sept. 23 in PLoS One, the online scientific journal of the U. S. Public Library of Science, scientists analyzed close to 300,000 patients admitted to state - run hospitals across England on those two Wednesdays from 2000 to 2008. The health of the patients, who were split evenly between the July and August admission days, was tracked for a week. While there was little difference between the crude death rates for each seven -day period, when researchers controlled for the patients' age, sex, socioeconomic status and secondary medical problems, the odds of dying was found to be 6% higher for those admired on the Wednesday in August. Among so - called medical achnissions - all those not suffering from cancer or requiring surgery -the odds were 8% higher. Should patients be nervous? Scientists have for years been examining the patient risk associated with a change over of medical staff Smaller studies conducted over the past two decades in Britain and the U. S. -where researchers label it the "July phenomenon," after the month in which medical students usually begin training--have often proved inconelusive. Even the "small but significant" discrepancy highlighted by Imperial' s study doesn't point to a particular cause. It' s possible that patients admitted on the days junior doctors began work were simply in worse health than those taken in the week earlier. Some hospitals may have been more reluctant to admit patients with less - serious problems on the days new staff started work, limiting the number of cases young medics had to deal with but increasing the concentration of acutely ill patients in the process. "So it may not necessarily be directly related to the quality of care, "says Paul Aylin, an epidemiologist at Imperial College London and senior author of the study.

{{U}} (46) {{/U}} Yet, after wrapping a flexible cuff around your arm and pumping it up, your doctor frowns and gives you the bad news:you are one of the roughly 60 million Americans who have high blood pressure. Because it can lurk in the body without your knowing it, high blood pressure has been called the silent killler. {{U}}(47) {{/U}} {{U}} (48) {{/U}} Depending on how high your pressure is, how you live and what changes you're willing to make in your lifestyle, treatment can be tailored specifically to you. {{U}} (49) {{/U}} The first, or top, number is the systolic reading, the pressure of blood against artery walls when the heart beats—the period of highest tension. The second, or bottom, number is the diastolic—the minimum pressure, between beats, when the heart is filling with blood and artery walls are relaxed. If the diastolic goes over 105 and stays there through several readings, that's the beginning of the danger zone, moderate hypertension, and continued monitoring is essential. Once the diastolic rises above 115, the condition is severe. A diastolic between 90 and 104 falls into the gray area of "mild" hypertension.{{U}} (50) {{/U}} A. These drugs can lower blood pressure by getting rid of excess fluid and salt in the body. B. It is the leading cause of strokes and a major factor in heart attacks and kidney failure. C. You've had no symptoms, no pain, no sense of being sick. D. For the average adult, a healthy blood-pressure reading is 120 over 80, or lower. E. Three-fourths of those with high blood pressure are in this category. F. The good news is that thanks to an explosion of research, science now knows how to defuse the danger, and control the disease.

下面的短文后列出了7个句子，请根据短文的内容对每个句子做出判断：如果该句提供的是正确信息，请选择A；如果该句提供的是错误信息，请选择B；如果该句的信息文中没有提及，请选择C。 {{B}}An Observation and an Explanation{{/B}} It is worth looking at one or two aspects of the way a mother behaves towards her baby. The usual fondling, cuddling and cleaning require little comment, but the position in which she holds the baby against her body when resting is rather revealing. Careful studies have shown the fact that 80 percent of mothers hold their infants in their left arms, holding them against the left side of their bodies. If asked to explain the significance of this preference most people reply that it is obviously the result of the predominance of right-handedness in the population. By holding the babies in their left arms, the mothers keep their dominant arm free for manipulations. But a detailed analysis shows that this is not the case. True, there is a slight difference between right-handed and left-handed females; but not enough to provide adequate explanation. It emerges that 83 percent of right-handed mothers hold the baby on the left side, but so do 78 percent of left-handed mothers. In other words, only 22 percent of the left-handed mothers have their dominant hands free for actions. Clearly there must be some other, less obvious explanation. The only other clue comes from the fact that the heart is on the side of the mother's body. Could it be that the sound of her heartbeat is the vital factor? And in what way? Thinking along these lines it was argued that perhaps during its existence inside the body of the mother the unborn baby get used to the sound of the heart beat. If this is so, then the re-discovery of this familiar sound after birth might have a claiming effect on the infant, especially as it has just been born into a strange and frighteningly new world. If this is so then the mother would, somehow, soon arrive at the discovery that her baby is more at peace if held on the left against her heart than on the right.

下面的短文有15处空白，请根据短文内容为每处空白确定1个最佳选项。 {{B}}Friends May Be Key to Living Longer{{/B}} Looking for the secret of a long life? Look closely at your friends. New research suggests that having a strong network of friends helps people live longer. "Older people with better social networks of friends were less likely to{{U}} (51) {{/U}}over a 10-year follow-up (随访) period than older people with{{U}} (52) {{/U}}friends networks," Lynne C. Giles of Flinders University in Australia told Reuters Health. But in what may come as a surprising finding to older people{{U}} (53) {{/U}}rely on their children and other relatives, having a large network of relatives was not associated with longer life, according{{U}} (54) {{/U}}Giles and her colleagues. "Of course, that is not to say that social networks{{U}} (55) {{/U}}children and other relatives are not important in many other ways," Giles said. Study after study has shown that elderly people who{{U}} (56) {{/U}}connected with lots of people tend to live longer lives.{{U}} (57) {{/U}}, few studies have examined whether different types of relationships - with friends, partners, children and{{U}} (58) {{/U}}relatives-have different effects on longevity (长寿). Giles's team set out to examine the relationship between various types of social networks and{{U}} (59) {{/U}}in a group of almost 1,500 Australians who were at least 70 years{{U}} (60) {{/U}}. Volunteers answered{{U}} (61) {{/U}}about their social networks and then were followed for 10 years. The researchers took into account several factors that could have influenced how long a person lived,{{U}} (62) {{/U}}sex, age, health and smoking status. What the study showed was{{U}} (63) {{/U}}Older people who reported better social networks of friends were{{U}} (64) {{/U}}likely to be alive at the end of the study than people with fewer friends. But relationships with children and other relatives did not have{{U}} (65) {{/U}}effect on survival in the study.

The basis for overhauling the country's tobacco regulations—and the opportunity to snag a huge windfall for the Treasury —{{U}} (46) {{/U}} State attorneys general had ganged up on the industry, suing for reimbursement of Medicaid and other patient-care costs incurred, they say, because of the companies' promotion of cigarette smoking. {{U}}(47) {{/U}} The companies offered to pay a whopping $ 368.5 billion to the plaintiffs and various governments over 25 years, accept strict regulation of their products, and curb advertising. {{U}}(48) {{/U}} The companies specifically asked Congress for a bar on class-action suits, protection from punitive damage awards for past deeds, and an annual limit of roughly $ 5 billion on damages awarded to individual plaintiffs. The proposal is stunning, but Congress didn't leap at the offer. Just days after these terms were unveiled, two of the nation's best known public health officials and antitobacco crusaders—former Surgeon General C. Everett Koop and former FDA Commissioner David Kessler, now dean of the Yale medical school—denounced the proposal. {{U}}(49) {{/U}}Koop told the reporters he was concerned that the public might be "snookered" by the cash offer. Koop and Kessler were later joined by other public health advocacy groups, including the American Lung Association and American Medical Association, in urging Congress not to accept the proposal without revision. Kessler says he thinks it is "unlikely that there will be a deal granting the industry immunity (from litigation), "because no one will want to accept the risk of being perceived as a friend of tobacco. Yet at the same time, Kessler says, "I'm all in favor of an excise tax on cigarettes" that would raise the price and make it harder for teenagers to buy cigarettes. He adds, "I am strongly in favor of using that money for biomedical research." {{U}}(50) {{/U}} A. On 20 June, the two negotiating teams unveiled a deal that they said could end the litigation and aid public health, if Congress could approve it. B. In return, they asked the federal government to shield them from certain legal bills C. arose last year in talks between 5 major tobacco companies and 40 states D. In short, cigarette smoking does nothing but harm to the people's health E. Kessler warns, however, that the federal government muse be careful not to get "hooked on tobacco money." F. Both argued that the settlement provided too little in return for indemnity from class-action suits.