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53-54考研英语阅读报刊资料

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- 53 - How does the brain know when carbohydrates have been or should be consumed? The answer to this question is not known, but one element in the explanation seems to be the neurotransmitter sero-tonin (血清素), one of a class of chemical mediators that may be released from a pre-synaptic neuron and that cause the transmission of a nerve impulse across a synapse (突触) to an adjacent postsynaptic neuron. In general, it’s been found that drugs that selectively facilitate serotonin-mediated neuro-transmission tend to cause weight loss, whereas drugs that block serotonin-mediated transmission often have the opposite effect: they often induce carbohydrate craving and consequent weight gain. Serotonin is a derivative of tryptophan (色氨酸), an amino acid that is normally present at low levels in the bloodstream. The rate of conversion is af-fected by the proportion of carbohydrates in an in-dividual’s die: carbohydrates stimulate the secretion of insulin, which facilitates the uptake of most amino acids into peripheral tissues, such as muscles. Blood tryptophan levels, however, are unaffected by insulin, so the proportion of tryptophan in the blood relative to the other amino acids increases when carbohydrates are consumed. Since tryptophan competes with other amino acids for transport across the blood-brain barrier into the brain, insulin secretion indirectly speeds tryptophan’s entry into the central nervous system where, in a special clus-ter of neurons, it is converted into serotonin. The level of serotonin in the brain in turn af-fects the amount of carbohydrate an individual chooses to eat. Rats that are allowed to choose among synthetic foods containing different propor-tions of carbohydrate and protein will normally al-ternate between foods containing mostly protein and those containing mostly carbohydrate. However, if rats are given drugs that enhance the effect of se-rotonin, the rats’ carbohydrate intake is reduced. On the other hand, when rats are given drugs that in-terrupt serotonin-mediated neurotransmission, their brains fail to respond when carbohydrates are eaten, so the desire for them persists. In human beings a serotonin-like drug, fenflu-ramine氟苯丙胺(which releases serotonin into brain synapses and then prolongs its action by blocking its re-absorption into the pre-synaptic neuron), se-lectively suppresses carbohydrate snacking (and its associated weight gain) in people who crave car-bohydrates. In contrast, drugs that block serotonin mediated transmission or that interact with neuro-transmitters other than serotonin have the opposite effect: they often induce carbohydrate craving and subsequent weight gain. People who crave carbo-hydrates report feeling refreshed and invigorated after eating a carbohydrate-rich meal (which would be expected to increase brain serotonin levels). In contrast, those who do not crave carbohydrates be-come sleepy following a high-carbohydrate meal. These findings suggest that serotonin has other ef-fects that may be useful indicators of serotonin le-vels in human beings.

1 Which one of the following best states the main idea of the passage? (A) The body’s need for carbohydrates varies with the level of serotonin in the blood (B) The body’s use of carbohydrates can be regu-lated by the administration of serotonin-like drugs (C) The role of serotonin in regulating the con-sumption of carbohydrates is similar in rats and in humans (D) The body’s desire for carbohydrates can be in-fluenced by serotonin or serotonin-like drugs (E) Tryptophan initiates a chain of events that regu-lates the body’s use of carbohydrates

2 The term “rate” (para.2) refers to the rate at which (A) serotonin is produced from tryptophan (B) carbohydrates are taken into the body (C) carbohydrates stimulate the secretion of insulin (D) insulin facilitates the uptake of amino acids into peripheral tissues (E) tryptophan enters the bloodstream

3 It can be inferred that a person is likely to crave carbohydrates when (A) the amount of insulin produced is too high (B) the amount of serotonin in the brain is too low (C) more tryptophan than usual crosses the blood- brain barrier (D) neurotransmission by neurotransmitters other than serotonin is interrupted (E) amino acids other than tryptophan are taken up by peripheral tissues

4 The information in the passage indicates that if human beings were given a drug that inhibits the action of serotonin, which one of the following might be expected to occur? (A) Subjects would probably show a preference for carbohydrate-rich snacks rather than protein-rich snacks (B) Subjects would probably become sleepy after eating a carbohydrate-rich meal (C) Subjects would be more likely to lose weight than before they took the drug (D) Subjects’ blood tryptophan levels would proba-bly increase (E) Subjects’ desire for both carbo-hydrates and proteins would increase

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考研英语阅读理解部分试题解析

考研英语阅读理解部分试题解析

Could the bad old days of economic decline beabout to return? Since OPEC agreed tosupply-cuts in March, the price of crude oil has jumped to almost $26 a barrel,up from less than $10 last December. This near-tripling of oil prices calls upscary memories of the 1973 oil shock, when prices quadrupled, and 1979-80, whenthey also almost tripled. Both previous shocks resulted in double-digitinflation and global economic decline. So where are theheadlines warning of gloom and doom this time? The oil price was given another push up this week when Iraqsuspended oil exports. Strengthening economic growth, at the same time aswinter grips the northern hemisphere, could push the price higher still in theshort term. Yet there are good reasons to expect the economic consequences nowto be less severe than in the 1970s. In most countries the cost of crude oilnow accounts for a smaller share of the price of petrol than it did in the1970s. In Europe, taxes account for up to four-fifths of the retail price, so evenquite big changes in the price of crude have a more muted effect on pump pricesthan in the past. Rich economies are also less dependent on oil than they were, and soless sensitive to swings in the oil price. Energy conservation, a shift toother fuels and a decline in the importance of heavy, energy-intensiveindustries have reduced oil consumption. Software,consultancy and mobile telephones use far less oil than steel or carproduction. For each dollar of GDP (in constant prices) rich economies now usenearly 50% less oil than in 1973. The OECD estimates in its latest EconomicOutlook that, it oil prices averaged $22 a barrel for a full year, comparedwith $13 in 1998, this would increase the oil import bill in rich economies byonly 0.25-0.5% of GDP. That is less than one-quarter of the income loss in 1974or 1980. On the other hand, oil-importing emerging economies—to which heavy industry has shifted—have become more energy-intensive,and so could be more seriously squeezed. One more reason not to lose sleep over the rise in oil prices isthat, unlike the rises in the 1970s, it has not occurred against the backgroundof general commodity-price inflation and global excess demand. A sizableportion of the world is only just emerging from economic decline. TheEconomist's commodity price index is broadly unchanging from a year ago. In1973 commodity prices jumped by 70%, and in 1979 byalmost 30%. 51. The main reason for the latest rise of oil price is ［A］ global inflation. ［B］ reduction in supply. ［C］ fast growth in economy. ［D］ Iraq's suspension of exports. 52. It can be inferred from the text that the retail price of petrolwill go up dramatically if ［A］ price of crude rises. ［B］ commodity prices rise. ［C］ consumption rises. ［D］ oil taxes rise. 53. The estimates in Economic Outlook show that in rich countries. ［A］ heavy industry becomes more energy-intensive. ［B］ income loss mainly results from fluctuating crude oil prices. ［C］ manufacturing industry has been seriously squeezed. ［D］ oil price changes have no significant impact on GDP. 54. We can draw a conclusion from the text that. ［A］ oil-price shocks are less shocking now. ［B］ inflation seems irrelevant to oil-price shocks. ［C］ energy conservation can keep down the oil prices. ［D］ the price rise of crude leads to the shrinking of heavy industry. 55. From the text we can see that the writer seems ［A］ optimistic. ［B］ sensitive. ［C］ gloomy. ［D］ scared. ⼀、⽂章结构分析 ⽂章⼤意：最近这次⽯油价格的⼤幅上涨的影响不会像以前那样严重。

考研英语阅读---2004 text3

考研英语阅读---2004 text3


2004 text 3
• When it comes to the slowing economy, Ellen Spero isn’t biting her nails just yet. But the 47-year-old manicurist isn’t cutting, filing or polishing as many nails as she’d like to, either. Most of her clients spend $12 to $50 weekly, but last month two longtime customers suddenly stopped showing up. Spero blames the softening economy. “I’m a good economic indicator,” she says. “I provide a service that people can do without when they’re concerned about saving some dollars.” So Spero is downscaling, shopping at middle-brow Dillard’s department store near her suburban Cleveland home, instead of Neiman Marcus. “I don’t know if other clients are going to abandon me, too.” she says.
2004 text 3
• When it comes to the slowing economy, Ellen Spero isn’t biting her nails just yet. But the 47-year-old manicurist isn’t cutting, filing or polishing as many nails as she’d like to, either. Most of her clients spend $12 to $50 weekly, but last month two longtime customers suddenly stopped showing up. Spero blames the softening economy. “I’m a good economic indicator,” she says. “I provide a service that people can do without when they’re concerned about saving some dollars.” So Spero is downscaling, shopping at middle-brow Dillard’s department store near her suburban Cleveland home, instead of Neiman Marcus. “I don’t know if other clients are going to abandon me, too.” she says.
高考英语一轮复习话题阅读素材53

高考英语一轮复习话题阅读素材53

2019届高考英语一轮复习话题阅读素材53 Fast-food Culture Serves up Super-size AmericansStop blaming people or their genes -- it's an abundance of unhealthy，heavily advertised，low-cost food that underlies the nation's obesity crisis.America is overlooking the real cause of its ever-expanding waistline. The problem isn't so much people's lack of self-control. It's a toxic food environment" -- the strips of fast-food restaurants along America's roadways，the barrage of hamburger advertising on television and the rows of candies at the checkout counter of any given convenience store.To be sure，genes and self-control play a role in obesity and the diabetes and other health problems that result. But，both face a losing battle against the ubiquity of bad food. Genetics is what permits the problem to occur，but environment is what drives it. The problem with medical and psychological interventions for individuals is that the costs of treatment outweigh the benefits，and weight-gain relapse rates remain high. Of particular concern is America's passive acceptance of unhealthy food. Americans fail to Recognize，for example，the possible damage done by such fast-food icons as Ronald McDonald.Certain "toxic signs" are alarming:Innutritious foods reign. High-fat，high-sugar foods are widelyavailable，taste good and cost less than healthier foods. Vending machines are ubiquitous，Kentucky Fried Chicken delivers and most fast-food outlets now serve breakfast.The food industry has run amok. Advertisements for prepackaged and fast foods saturate the airwaves，newspapers and magazines.Physical activity has declined. Most Americans get less exercise than ever -- walking less and driving more.As further evidence that environment is to blame，obesity has risen notably in other countries，including China，and that migrants to Western countries have much higher obesity rates than their relatives back home. Particularly vulnerable to the problem are American children. Parents can't win this battle alone. But they might stand a chance through the following proposed policy changes:Make activity more accessible，by，for example，building communities to allow more walking or biking. Regulate TV food ads aimed at children and mandate equal time for pro-nutrition messages. Ban fast foods and soft drinks from schools，instead forging school contracts with sports-related companies. Subsidize healthy foods and drive down process of fruits and vegetables by 70 percent.Such measures would take the blame off people with obesity and are the only real path to doing something constructive about this problem.。

2020考研英语复习：历年考研试题阅读文章来源汇总（上）

2020考研英语复习：历年考研试题阅读文章来源汇总（上）

2020考研英语复习：历年考研试题阅读文章来源汇总（上）考研是孤单而又曲折的道路，但强者之路总是孤独的，下面由小编为你精心准备了“2020考研英语复习：历年考研试题阅读文章来源汇总(上)”，持续关注本站将可以持续获取更多的考试资讯！2020考研英语复习：历年考研试题阅读文章来源汇总2016年考研阅读1.2015年4月5日《基督教科学箴言报》(TheChristian Science Monitor)2.2014年11月15日《卫报》(The guardian)3.2015年7月23日的《经济学家》(Economist)4.2015年3月26日《美国大西洋月刊》(TheAtlantic)2015年考研阅读1.6/4/2014《卫报》( The guardian)2.4/28/2014《华盛顿邮报》(TheWashingtonPost)3.7/3/2014《自然杂志》( Nature )4.6/29/2014《卫报》(The Guardian)2014年考研阅读：1- 2013年6月29日的《卫报》(Theguardian)2- 2013年2月2日的《经济学家》(The Economist)3- 2013年6月12日的《自然杂志》(Nature)4- 2013年7月1日的《华尔街日报在线》The Wall StreetJournal Online2013年考研阅读：1- 2012年6月21日的《商业周刊》(Businessweek)2- 2012年6月9日的《经济学家》(TheEconomist)3- 2012年5月23日的《科学美国人》(ScientificAmericans)4- 2012年6月25日的《华尔街日报》(TheWall StreetJournal) 2012年考研阅读：1- 2011年3月24日的《时代周刊》(Times)2- 2011年4月24日的3- 一本书《EverydayPractice of Science: Where Intuitionand Passion Meet Objectivity and Logic》4- 2011年3月17日的《经济学家》(Economist)新题型：2011年7月5日的《新科学家》(New scientist)翻译：2011年4月20日的《自然杂志》(Nature)2011年考研阅读：1- 2007年9月《社评杂志》(commentarymagazine)2- 2009年11月《商业周刊》(Business week)3- 2010年1月《福布斯》(Forbes)4- 2010年7月9日《新闻周刊》(News Week)新题型：一本书《Professionalizingthe professor：the difficultiesof an American doctoralstudent University education in America》翻译：一本书《Fifty self-helpclassics》2010年考研阅读：1- 不详2- 2008年2月26号的《商业周刊》(Business week)3- 2007年2月的《哈佛经济评价》(HarvardBusiness Review) 4- 2009年4月的《经济学家》(The Economist)新题型：2008年4月美国哥伦比亚广播公司新闻报道(CBS)完形填空：2009年6月6日《经济学家》(The Economist)翻译：一本书A Sand CountyAlmanac(Aldo Leopold)2020考研英语复习：历年考研试题阅读文章来源汇总(下) 2009年考研阅读：1- 2008年5月4日的《纽约时报》(The New YorkTimes)2- 2008年1月1日的《科学美国人》(ScientificAmerican) 3- 2003年12月的《麦肯锡季刊》(The MckinseyQuarterly) 4- 不详新题型：微软百科在线的一篇文化类文章(已删除)2008年考研阅读：1- 2006年12月的《科学探索》(Discovery)2- 2005年9月22日的《经济学家》(The Economist)3- 2001年7月的《科学美国人》(ScientificAmerican)4- 2004年1月的《美国新闻》(U.S. News)完型填空：2005年6月2号的《经济学家》(The Economist)翻译：木书屋达尔文传(wooden horsebooks)2007年考研阅读：1- 2006年5月7日的《纽约时报》(he New YorkTimes)2- 2001年5月的《科学美国人》(ScientificAmerican)3- 2001年6月的《哈佛杂志》(HarvardMagazine)4- 2005年6月的《经济学家》(The Economist)新题型：2005年1月的《时代周刊》(Times)2006年考研阅读：1- 不详2- 2000年11月的《观察家报》(The Observer)3- 2003年5月15日的《经济学家》(The Economist)4- 2005年1月17日的《时代周刊》(Times)2005年考研阅读：1- 2003年9月20日的《经济学家》(The Economist)2- 2001年6月25日的《美国新闻报道》(U.S. News andReport) 3- 2002年7月15日《新闻周刊》(News Week)4- 2004年1月31日《经济学家》(The Economist)2004年考研阅读：1- 1997年10月27日的《美国新闻报道》(U.S. News andReport)2- 2001年9月1日的《经济学家》(The Economist )3- 2002年7月15日的《新闻周刊》(News Week)4- 2001年1月的《美国学校董事会杂志》(ASBJ)2003年考研阅读：1- 1999年1月25日的《时代周刊》(Times)2- 1998年11月20日的《科学》(Science)3- 不详4- 2001年8月27日的《新闻周刊》(News Week)。