Scientists have developed a slimming drug that successfully suppresses appetite and results in a dramatic loss of weight without any apparent ill effects. The drug interferes with appetite control and prevents the build-up of fatty tissue. More importantly, the drug appears to prevent a serious decline in metabolic rate-causing tiredness and lethargy—which is typically associated with living on a starvation diet. As a result, mice taking the drug lost 45 percent more weight than mice fed the same amount of food, which compensate for the lack of food by becoming more sluggish. The scientists, from the Johns Hopkins University in Baltimore, said that C 75 is likely to produce a similar effect on humans because appetite control in the brain is thought to be based largely on the same chemical pathways as those in mice. " We are not claiming to have found the fabled weight-loss drug. What we have found, using C 75, is a major path way in the brain that the body uses naturally in regulating appetite at least in mice," said Francis Kuhajda, a pathologist and senior team member. "We badly need effective drugs for weight loss. Obesity is a huge problem. We"re hoping to explore the possibilities of this new pathway," he said. Discovering a biochemical pathway in the brain that controls appetite raises new prospects for developing slimming aids. Research on leptin, a hormone produced in fatty tissue for controlling fat deposits, has so far failed to produce the expected slimming drug break-through. The latest study, published in the journal Science, showed that even moderate doses of C 75 produced a significant loss of appetite, which returned to normal after a few months. The scientists believe that C 75, which they produced synthetically in the laboratory, binds to an enzyme called fatty acid sythase, which is involved in storing excess food intake as fat. Inhibiting the enzyme causes a build-up of a chemical in the liver which acts as a precursor to fat deposition. This precursor is thought to have an indirect effect on the brain, causing appetite suppression. Normally, when animals fast, a hormone called neuropeptide Y increases sharply in the appetite control centers of the brain, stimulating the desire for food. However, when animals are given C 75, levels of this hormone fall, leading to a loss of interest in food. Dr Kuhajda said discovering that C 75 has no effect on metabolic rate is one of the most significant findings of the study. "If you try to lose weight by starving, your metabolism slows down after a few days," he said. " It" s a survival mechanism that sabotages many diets. We see this in fasting mice. Yet metabolic rate in the C 75-treated mice doesn"t slow at all. " Further animals studies will be needed before C 75 could be tested on humans. The newly-found slimming drug can successfully suppress appetite because______.
A. C 75 made synthetically in the laboratory works effectively on human body
B. fatty acid sythase is involved in storing excess food intake as fat
C 75 inhibits the activity of an enzyme called fatty acid sythase
D. it increases a hormone called neuropeptide Y in the appetite-control centers of the brain
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For eight months he has floated in his private ocean. This morning he awakens, opens his eyes, yawns and kicks vigorously several times. His umbilical cord drifts by his questing fingers. He plays with it briefly, brings his hands up to his mouth and sucks his thumb. Over his mother" s heartbeat and the gurgles of her digestive tract, he can hear her talking with his father. Interested, he stops sucking to listen. Until recent years, we could only speculate on what life was like for an unborn baby. Then, major advances inultrasound scanningbegan opening a window to the womb; doctors could view every movement of the baby on a television—like screen. The pictures show unborn babies yawning, sucking, grasping, stretching, blinking and making faces—in short, all the things they will do after birth. Normally an unborn baby never experiences hunger or thirst. But if a mother does not consume sufficient nutrients, the baby" s diet will not be adequate either. When an unborn baby is severely malnourished—for instance, because his mother" s heavy smoking restricts blood flow to the placenta—Dr, Jason Birnholz, an ultrasound expert, believes he has seen the baby" s chest and throat making crying motions. A radio startles him awake. He blinks and grimaces at the new sensation, but then becomes interested in the music. He turns his head to bring his ear closer to the outside world. He notices the pressure of the book his mother is resting on her belly. He kicks at it, her laugh comes to him as a dull, echoing rumble. She pats the spot he kicked and, entering into the spirit of the game, he kicks back. They play several rounds before he loses interest and falls asleep. Can a mother" s stress, anger, shock or grief harm her baby No. The normal stresses and strains of life won" t hurt him. As the expert Maurers put it, such periods are the womb equivalent of having a spell of " bad weather". Some are startled when exposed to a series of loud buzzes, but some then turn an ear to listen. Severe continuous stress may be another story. It remains unclear whether problems arise from the stress itself or from the poor nutrition, smoking, drinking or drug taking that likely accompany it. In any case the baby is affected. The passage suggests that______.
A. the severe anger of the mother will affect the unborn baby
B. bad weather does no harm to the babies in the wombs
C. some of the unborn babies are more interested in music
D. most of the unborn babies enjoy the good weather
Most patients respond to the awareness that they have a terminal illness with the statement, "Oh no, this can"t happen to me. " After the first shock, numbness, and need to deny the reality of the situation, the patient begins to send out cues that he is ready to "talk about it". If we, at that point, need to deny the reality of the situation, the patient will often feel deserted, isolated, and lonely and unable to communicate with another human being what he needs so desperately to share. Most patients who have passed the stage will become angry as they ask the question, "Why me" Many look at others in their environment and express envy, jealousy, anger, and rage toward those who are young, healthy, and full of life. These are the patients who make life difficult for nurses, physicians, social workers, clergymen, and members of their families. Without justification they criticize everyone. What we have to learn is that the stage in terminal illness is a blessing, not a cure. These patients are not angry at their families or at the members of the helping professions. Rather, they are angry at what these people represent; health and energy. Without being judgmental, we must allow these patients to express their anger and dismay. We must try to understand that the patients have to ask, "Why me" and that there is no need on our part to answer this question concretely. Once a patient has ventilated his rage and his envy, then he can arrive at the bargaining stage. During this time, he" s usually able to say, "Yes, it is happening to me—but". The"but" usually includes a prayer to God; "If you give me one more year to live, I will be a good Christian. " How many stages can a patient with terminal illness pass through in facing death
A. Two.
B. Three.
C. Four.
D. Five.
下列属于会计软件数据最基本的输出形式是______。
A. 向磁盘输出
B. 查询与打印
C. 网络传输输出
D. 备份
Charles Paul and his wife, Hazel, stopped using the motor home they bought several years ago; it sits idle behind their house in Richardson, Texas. Travel is just one sacrifice they made to pay for the cost of their prescriptions, more than a dozen medications for the two of them. They found relief by switching drugstores, to one in nearby McKinney. A prescription for Paul" s diabetes had cost $ 89. 88 when he got it from a national chain but dropped down to $ 58 from McKinney" s Smith Drug. Smith, which claims to be the oldest drugstore in Texas, has been getting a lot of attention since a Dallas newspaper touted its astoundingly low prices. The overwhelming response from the public has been " a little scary," says co-owner Kaylei Mosier. She says the store simply marks each prescription up enough to cover its costs, but for many prescriptions that" s a lot lower than at other stores. The Smith Drug story has highlighted a little-known fact: prescription prices vary from city to city and block to block, and a little research can save consumers hundreds or thousands of dollars. Insurance copays can make these differences invisible, but they" re a huge deal to the 45 million uninsured Americans. Why the price swings Howard Schiff, executive director of the Maryland Pharmacists Association , explains that pharmacies generally buy their drugs from a wholesaler, who doesn" t sell to every drugstore at the same price. Once the drug is in the pharmacy, each owner chooses how much to mark it up. Because fewer than 10 percent of consumers comparison-shop for prescriptions the way they might for a quart of milk—and drug prices generally are not advertised—pharmacies don" t worry that higher prices will drive people away, says Stanford economist Alan Scorensen. There is a downside to hopping from drugstore to drugstore. If people price-shop, they" re going to lose some protection that comes from having one pharmacy track all your medications. Going to many pharmacies keeps one pharmacist from noticing potentially harmful interactions between prescriptions. Comparison-shopping is further complicated because pharmacies that have the best price on one drug don" t usually have the lowest prices across the board, so finding a good price on one drug at a pharmacy does not guarantee a cheaper total bill. The word "downside" used in the last paragraph refers to______.
A. the poor service in tracking medications
B. the trend of reducing drug prices
C. the popularity of comparison-shopping
D. the drawback of switching drugstores