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Eat More, Weigh Less, Live Longer Clever genetic detective work may have found out the reason why a near-starvation diet prolongs the life of many animals. Ronald Kahn at Harvard Medical School in Boston, U.S., and his colleagues have been able to extend the lifespan (寿命) of mice by 18 per cent by blocking the rodent’s (啮齿动物) increase of fat in specific cells. This suggests that thinness--and not necessarily diet--promotes long life in "calorie (热量卡) restricted" animals. "It’s very cool work," says aging researcher Cynthia Kenyon of the University of California, San Francisco. "These mice eat all they want, lose weight and live longer. It’s like heaven." Calorie restriction dramatically extends the lifespan of organisms as different as worms and rodents. Whether this works in humans is still unknown partly because few people are willing to submit to such a strict diet. But many researchers hope they will be able to trigger the same effect with a drug once they understand how less food leads to a longer life. One theory is that eating less reduces the increase of harmful things that can damage cells. But Kahn’s team wondered whether the animals simply benefit by becoming thin. To find out, they used biology tricks to disrupt the insulin (胰岛素) receptor (受体) gene in lab mice, but only in their fat cells. "Since insulin is needed to help fat cells store fat, these animals were protected against becoming fat," explains Kahn. This slight genetic change in a single tissue had dramatic effects. By three months of age, Kahn’s modified mice had up to 70 per cent less body fat than normal control mice, despite the fact that they ate 55 per cent more food per gram of body weight. In addition, their lifespan increased. The average control mouse lived 753 days, while the thin rodents averaged a lifespan of 887 days. After three years, all the control mice had died, but one-quarter of the modified rodents were still alive. "That they get these effects by just manipulating the fat cells is controversial," says Leonard Guarente of the Massachusetts Institute of Technology, who studies calorie restriction and aging. But Guarente says Kahn has yet to prove that the same effect is responsible for increased lifespan in calorie-restricted animals. "It might be the same effect or there might be two routes to long life," he points out, "and that would be very interesting.\ The average modified mouse lived ______.
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Eat More, Weigh Less, Live Longer Clever genetic detective work may have found out the reason why a near-starvation diet prolongs the life of many animals. Ronald Kahn at Harvard Medical School in Boston, U.S., and his colleagues have been able to extend the lifespan (寿命) of mice by 18 per cent by blocking the rodent’s (啮齿动物) increase of fat in specific cells. This suggests that thinness--and not necessarily diet--promotes long life in "calorie (热量卡) restricted" animals. "It’s very cool work," says aging researcher Cynthia Kenyon of the University of California, San Francisco. "These mice eat all they want, lose weight and live longer. It’s like heaven." Calorie restriction dramatically extends the lifespan of organisms as different as worms and rodents. Whether this works in humans is still unknown partly because few people are willing to submit to such a strict diet. But many researchers hope they will be able to trigger the same effect with a drug once they understand how less food leads to a longer life. One theory is that eating less reduces the increase of harmful things that can damage cells. But Kahn’s team wondered whether the animals simply benefit by becoming thin. To find out, they used biology tricks to disrupt the insulin (胰岛素) receptor (受体) gene in lab mice, but only in their fat cells. "Since insulin is needed to help fat cells store fat, these animals were protected against becoming fat," explains Kahn. This slight genetic change in a single tissue had dramatic effects. By three months of age, Kahn’s modified mice had up to 70 per cent less body fat than normal control mice, despite the fact that they ate 55 per cent more food per gram of body weight. In addition, their lifespan increased. The average control mouse lived 753 days, while the thin rodents averaged a lifespan of 887 days. After three years, all the control mice had died, but one-quarter of the modified rodents were still alive. "That they get these effects by just manipulating the fat cells is controversial," says Leonard Guarente of the Massachusetts Institute of Technology, who studies calorie restriction and aging. But Guarente says Kahn has yet to prove that the same effect is responsible for increased lifespan in calorie-restricted animals. "It might be the same effect or there might be two routes to long life," he points out, "and that would be very interesting.\ What can be inferred from the passage about the route to long life
A. The Organization of An ArticleB. Check Your Reading SpeedC. A Way to Increase Your Reading SpeedD. Check Your UnderstandingE. Read Something Every DayF. Read Extensively Paragraph 2 ______
Online Cancer Chat with a Safety Net Cancer Research U.K. has lanched an online chat forum for cancer patients to swap stories and share experiences on how to cope with such a devastating disease. But Cancer Chat is a forum with a difference: it has an information safety net. This means that a Cancer Research U.K. team will keep a watching brief to ensure that patients are not subjected to rogue "cancer cures" or scientifically unsound information. Anyone can have access to the messages posted on Cancer Chat but if people wish to post a message they will need to register. And Rebekah Gibbs, cancer patient and star of TV’s Casualty has pledged her support for the new project. "I think Cancer Chat is a brilliant idea," she said. "I have written a public diary about what I went through with breast cancer and I have had such a heart-warming response from other people going through the same thing. "The idea of a Cancer Chat forum means you can share information about treatment and side effects and you can really open up about your feelings online in a way that can be difficult when talking to close friends and family. And with Cancer Research U.K. monitoring the forum people can be reassured about the quality of information being exchanged. " Cancer Chat will also encourage its users to check out any cancer questions on its CancerHelp U.K. website which is specially designed to give patients and their families 6,000 pages of up-to-date information that is easy to understand and explains a wide range of treatments for different types of cancer and gives details of clinical trials. There is also a U.K. database of cancer clinical trials. The award-winning website attracts around one million visitors a month and Cancer Research U.K. hopes that some of these visitors will also want to post comments on the Cancer. For those who do not have access to computers and have questions about cancer, the charity’s team of cancer information nurses are available during office hours to talk over patients’ concerns on the phone. "The charity" in the last line but one refers to ______.
Florence Nightingale In 1837, to the age of seventeen, Florence Nightingale decided to become a nurse, (51) horrified her dear mother. In (52) days, nurses were little more than doormen, and hospitals were places of dirtiness and (53) . Nightingale pressed on and in 1853 she became president (54) a small London hospital. She went on to the Crimea when war (55) there between Britain and Russia. She (56) the first of what we now know (57) war hospitals: sanitary. safe, and stocked with supplies. Her tireless ministrations (照料) to the (58) soldiers made her famous all (59) the world. Following the War, Nightingale (60) fame and continued to train nurse, ever battling (61) what she herself declared "a commonly received idea...that it requires nothing (62) a disappointment in love, or incapacity in other things, to turn a woman (63) a good nurse." Since 1921, her birthday (64) the centerpiece of National Hospital Week, (65) in British and American hospitals with special exhibitions, workshops, and publicity drives.
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