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.

Robert Beckett, who broke his leg and had to have it set at the local hospital, was given something to put him to sleep while this rather painful process was going on. All he remembered afterward was that a white-coated man made a prick in his arm—the body hardly felt it—and then sat down beside him and asked him to count slowly to ten.{{U}} (46) {{/U}} {{U}} (47) {{/U}} While Robert was couting, the anaesthetist was pressing the plunger of the syringe and injecting into his arm a small amount of liquid that looked like water. The liquid was not water, but a solution containing a drug that was powerful enough to put Robert to sleep and keep him there while his leg was being set. The same drug would not have been powerful enough to keep Robert unconscious had he required serious surgery. For operations where the patient must remain unconscious for an hour or more, the anaesthetist must administer the right amount of anesthetic continuously. {{U}}(48) {{/U}} It is usually not an injection, but a kind of gas that the patient breathes in through a mask placed over his face. {{U}} (49) {{/U}} Like most other early medicines, they were extracted from plants. Four plants producing such drugs were particularly well know—the poppy, henbane, hemp and mandrake. Poppies are still used as a source of morphine, a very widely used drug. {{U}}(50) {{/U}} Today hemp is most often used as raw material from which rope is made, but it is still known in parts of Central South America as "the weed that intoxicates". The other herb, mandrake, is almost unknown today, but it was widely used among the ancient Egyptians, the Greeks, and peoples of the Far East. According to one legend, the mandrake plant, when pulled from the ground, was supposed to give an unearthly shriek, so dreadful that a person who heard it died or went mad. A. The type of anesthetic he uses depends on the patient and the type of surgery to be performed. B. Robert got as far as seven, then woke up in bed with his leg in plaster. C. The prick that he felt was caused by the hollow needle of a hypodermic syringe. D. That was the state of affairs until the beginning of the last century. E. Henbane is not so well known, though it is still used in some medicines. F. Drugs that cause unconsciousness and kill pain are not new.

Three basic pathophysiologic mechanisms lead to virtually all the clinical disease states involving endocrine glands: {{U}}(46) {{/U}} the excessive hormone production and action and neoplasa. Deficiency of hormone action is most commonly caused by an abnormally low level of biologically active hormone reaching target tissues. {{U}}(47) {{/U}} Endocrine gland hypofunciton may be congenital, caused by a complete failure of gland development, a mutant gene-encoding the structure of hormone or an enzyme responsible for hormone biosythesis. {{U}} (48) {{/U}} replacement by tumor, surgical extirpation, effects of pharmacologic or environmental agents, or inflammation. Other causes of decreased hormone action in target tissues are encountered less frequently. Deranged physiologic control of pituitary gland function causes secondary glandular failure, which can be either congenital or acquired {{U}}(49) {{/U}} Defective postsecretory hormone activation or accelerated hormone metabolism may result in abnormally low hormone activity. Hormonal deficiency states, despite normal or even elevated concentrations of biologically active hormone in the circulation, may be due to target-tissue resistance. {{U}} (50) {{/U}} This failure of target tissue responsiveness may be due to an abnormality of hormone receptors or in post-binding signaling of the hormone-receptor interaction. A. Deficiency of hormone action on target tissues. B. Improvement of hormone release may result in glandular hypofunction. C. Functional endocrine tumors secrete a hormonal product. D. Inadequate hormone production may occur as a result of primary gland failure. E. Resistance can be congenital or acquired F. Endocrine gland failure may also be acquired as a consequence of physiologic atrophy.

Motoring Technology 1.2 million road deaths worldwide occur each year, plus a further 50 million injuries. To reduce car crash rate, much research now is focused on safety and new fuels—though some electric vehicle and biofuel research aims at going faster. Travelling at speed has always been risky. One cutting edge area of research in motoring safety is the use of digital in-car assistants. They can ensure you don"t miss crucial road signs or fall asleep. The use of artificial intelligence software allows these assistants to monitor your driving and makes sure your phone or radio doesn"t distract you at a vital moment. Most crashes result from human and not mechanical faults. Some safety developments aim to improve your vision. Radar can spot obstacles in fog, while other technology "sees through" high-sided vehicles blocking your view. And improvements to seat belts, pedal controls and tyres are making driving smoother and safer. The colour of a car has been found to be linked with safety, as have, less surprisingly, size and shape. And alternatives to fossil-fuel based petrol, such as plant oils, are a hot area of research. Fuel cells based on hydrogen burn cleanly, and are the subject of a serious research effort. But whatever is in the fuel tank, you don"t want a thief in the driving seat and there have been many innovations, some using satellite tracking and remote communications, to fight against car theft. These communication systems can also come into play if you crash, automatically calling for help. Accidents cause many traffic jams, but there are more subtle interplays between vehicles that can cause jams even on a clear but busy road. Such jams can be analysed using statistical tools. Robotic drivers could be programmed to make traffic flow smoothly and will perhaps one day be everyone"s personal chauffeur, but their latest efforts suggest that won"t be soon.

语法与词汇John has always remained (loyal) to his family and friends.

语法与词汇Einstein''s theory of relativity seemed (incredible) when it was first introduced.

语法与词汇It is taken for granted that a piano without any (defects) would produce very grand music.

语法与词汇During the United States Civil war, many people in the south were forced to (flee) their home.

语法与词汇Experiments enable young scientists to judge accurately what must be accepted and what must be viewed with (suspicion).

语法与词汇The development of the transistor and integrated circuits revolutionized the electronics industry by allowing components to be packaged more (densely).

语法与词汇Everybody {{U}}was glad to{{/U}}see Mary back

语法与词汇He has (thought out) the best way of saving oil for your car.