单选题 Once upon a time， staying a healthy weight was easy. To lose weight you simply had to practise the reverse of home economics-spend more than you earned. Unfortunately for many, but perhaps not surprisingly, {{U}}it turns out that{{/U}} {{U}}eople are rather more complicated than bank accounts{{/U}}. To stay a healthy weight, you need a hormone called leptin to work properly. It sends "I'm full" messages from the fat cells up to the brain，where they go, among other places, to the same pleasure centers that respond tO drugs like cocaine. Obese people produce plenty of leptin, but the brain doesn't seem to respond to it properly. Last year, researchers at the Oregon Research Institute scanned the brains of overweight people and found their reward circuits were underactive. They were eating more to try to get the enjoyment they were missing. There's a lot of evidence for the fact that most, if not all, of us have a set point around which our weight can vary by about seven to nine kilos, but anything beyond that is a real struggle. Making changes is hard, particularly if your body is working against you. So why not ditch the traditional approaches and try some new methods, based on the latest research, that work with your body rather than against it. Several years ago researchers at the National Institute on Aging in Baltimore reported that when they gave rats very little food one day and allowed them to eat plenty the next, they showed virtually all the benefits of a permanent calorie restriction diet. The same goes for humans, according to Dr.James Johnson. How does it work?Besides forcing the body to burn fat, it may also trigger hormonal changes. Most people say that the diet takes a bit of getting used to, but is not as {{U}}grindng{{/U}} as trying tO cut back on an everyday basis. Older dieters may remember something called brown fat. Unlike the undesirable white stuff, this was a dieter's dream. Instead of storing excess energy as fat, brown-fat tissue burned it off to keep you warm—at least in mice. Brown fat fell out of favor because researchers couldn't find much in humans but now, thanks to the New England Journal of Medicine, it's back in fashion. The idea is to expose people to cold temperatures. They then make more brown fat and their weight drops.

单选题The heavy earthquake occurred in the afternoon, causing an {{U}}inconceivable{{/U}} damage. A. unnecessary B. unreasonable C. unavoidable D. unbelievable

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单选题As in the rest of the continent, South Africa still has to {{U}}contend with{{/U}} overwhelming poverty. A. suffer from B. bring about C. invest in D. fight against

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单选题One way to maintain social stability is to {{U}}crack down{{/U}} on crime while creating more jobs. A. clamp down on B. settle down to C. look down upon D. boil down to

单选题This young lawyer dares to take on the powerful on behalf of the poor and weak. A. with the favor of B. find good jobs for C. assume the responsibility for D. accept the challenge of

单选题The difficulties facing these hikers {{U}}stem from{{/U}} the bad weather they have been having. A. cling to B. arise from C. result in D. compensate for

单选题Novel drugs developed through biotechnologies can be expected to {{U}}deliver{{/U}} a better effect. A. distribute B. produce C. liberate D. express

单选题On Christmas Eve in America the shopping malls are {{U}}saturated{{/U}} with shoppers in a frantic competition for last minute gifts. A. bustled B. soared C. filled D. broadened

单选题The massacre of innocent people cannot ever be {{U}}condoned{{/U}}. A. overlooked B. praise C. condemned D. satisfied

单选题This honor recognizes the work done by these private enterprises on behalf of charity. A. in the face of B. in the process of C. in the course of D. in the interests of

单选题Students of English are advised to try to ______ the meaning of a new word from the context. A. turn out B. figure out C. look out D. put out

单选题 Passage Three "I smoke for my health," I proclaimed in a newspaper article published in 1979. Since I am a doctor, this advice attracted amused attention. I reasoned that smoking made me cough and thus prevented pneumonia; smoking made my heart go faster and eliminated the need for special exercise; smoking restrained my appetite and kept me trim. And then, at 51, I had a heart attack. I knew the risk factors for early heart disease, high blood-cholesterol levels and smoking. The first four were in my favor, but 1; chose to smoke. Strange how the evidence that linked smoking to heart disease appeared unclear to me, and how the same data now appear overwhelmingly convincing. Why stop now? Smokers who stop after their first heart attack have an 80-percent chance of living ten more years—if they don't, a 60-per cent chance. As a smoker, I always resented the fact that we smokers received only scorn from nonsmokers. How could nonsmokers know that smoking was bad for the health if there were no smokers to prove it? Being a member of the experimental group, rather than the control group, deserves a certain measure of social appreciation. I've done my time. I'm now ready to be a control. No longer smoke for my health. My health can't stand the help. Will I miss the late-night trips to find a store that's still open and selling cigarettes? Will I miss searching through ashtrays (烟灰缸) to find the longest butt that is still smokable? Only time will tell. Not smoking may give me the time to find out. Was it easy to stop? Sure. Here is all you have to do. First, experience a severe crushing pain under your breastbone as you finish a cigarette. Next, have yourself admitted to a coronary-care(心脏康复) unit and be stripped of your clothing and belongings. Finally, remain in the unit at ad-solute bed rest for four days while smoking is forbidden. This broke my had-it. See if it works for you.

单选题Something worth doing is none______for being done twice,

单选题A careful {{U}}screening{{/U}} of the disease will lessen the patients' anxiety. A. showing B. hiding C. investigation D. projection

单选题Many people came to donate blood {{U}}of their own accord{{/U}}. A. willingly B. for their own sake C. of their own D. without the help of others

单选题Obama's high-profile failure to win the Olympics for Chicago could feed negative {{U}}narratives{{/U}} nipping at his heels. A. attitudes B. accounts C. impacts D. responses

单选题Fearful of losing her job for good, this lady decided to talk to the manager directly. A. for benefits B. by luck C. for ever D. at hand

单选题Humans have to settle the problems with food, clothes and______before they can survive. A．cabin B．mansion C．shed D．shelter