单选题The bodies of Burke's and Ham's victims couldn't be found by the police because

单选题The room is dim and quiet.

单选题 Stress at Work and Still Healthy The term could yet become the word of the year: stress is on everyone's lips these days and everywhere. Not only managers, officials and teachers are complaining nowadays, housewives, children and pensioners now also have their own problems. They too sacrifice themselves for others, feel under- or overworked and quickly lose their inner balance. Irritation, tiredness and exhaustion quickly follow. But that is only the negative aspect. Stress, after all, is also linked to positive terms such as joy of life, tension and vitality (活力). "Firstly, stress is healthy," says Wolfgang Stehling from Eltvelle. The doctor and management consultant says: "It occurs when the body loses its inner balance, but then stress hormones are produced to re-establish the balance." Thus stress is nothing more than a positive reaction of the body to pressure. It is unavoidable as part of our nature: "There is no such thing as a stress-free life." But whether stress leads to tensions in the mind or to tenseness of the muscles depends on the duration (持续时间), its cause or causes and the sufferer's personal situation. People who have trouble sleeping or suffer from bad moods or simply the flu will not be on top of the world and will take every little strife as negative stress. Others, people who feel refreshed at every new turn, are relaxed and successful, will view a difficult round of negotiations or competition at work more as a positive challenge than a cross to bear. Exercise, healthy eating and relaxation are thus the three pillars by which stress can be conquered almost every time. These factors form a unit, explains Marita Voelker-Albert, spokeswoman for the government's Nutrition Advice Center in Cologne. Its campaign "Gut Drauf" (Feeling Good) is targeted at young people. The government agency's research suggests that three out of four adolescents feel tired, overtaxed (负担过重) and under stress. Eating disorders and complaints such as migraines (偏头痛) and indigestion (消化不良), nervousness and concentration problems have increased among 12-to 16-year-olds. But even the best solutions don't work if they are not put into practice, says Stehling. Anybody who goes jogging regularly, practices yoga (瑜伽功) and prescribes good literature as a cure for negative stress, may well end up under more pressure as he tries to find the time for it all. Sometimes, says the consultant, it helps to take time out to reduce stress levels over a weekend.

单选题 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, US, 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 hot 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, those 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."

单选题Don't get {{U}}slack{{/U}} at you work.

单选题Be Alert to Antimicrobial(抗微生物的)Resistance The ability of micro-organisms to find ways to avoid the action of the drugs used to cure the infections they cause is increasingly recognized as a global public health issue. Some bacteria have developed mechanisms which make them resistant to many of the antibiotics(抗生素 ) normally used for their treatment. They are known as multi-drug resistant bacteria, posing particular difficulties, as there may be few or no alternative options for therapy. They constitute a growing and global public health problem. WHO suggests that countries should be prepared to implement hospital infection control measures to limit the spread of multi-drug resistant strains(菌株)and to reinforce national policy on prudent use of antibiotics, reducing the generation of antibiotic resistant bacteria. An article published in The Lance! Infectious Diseases on 11 August 2010 identified a new gene that enables some types of bacteria to be highly resistant to almost all antibiotics. The article has drawn attention to the issue of antimicrobial resistance, and, in particular, has raised awareness of infections caused by multi-drug resistant bacteria. While multi-drug resistant bacteria are not new and will continue to appear, this development requires monitoring and further study to understand the extent and modes of transmission, and to define the most effective measures for control. Those called upon to be alert to the problem of antimicrobial resistance and take appropriate action include consumers, managers of hospitals, patients, as well as national governments, the pharma-ceutical(制药的) industry and international agencies. WHO strongly recommends that governments focus control and prevention efforts in the following areas like surveillance for antimicrobial resistance; rational antibiotic use, including education of healthcare workers and the public in the appropriate use of antibiotics; introducing or enforcing legislation related to stopping the selling of antibiotics without prescription; and strict adherence to infection prevention and control measures, including the use of hand-washing measures, particularly in healthcare facilities. Successful control of multidrug-resistant microorganisms has been documented in many countries, and the existing and well-known infection prevention and control measures can effectively reduce transmission of multi-drug resistant organisms if systematically implemented. WHO will continue to support countries to develop relevant policies, and to coordinate international efforts to combat antimicrobial resistance. Antimicrobial resistance will be the theme of WHO's World Health Day 2011.

单选题Laster beams can be used to {{U}}bore{{/U}} metals and other hard materials. A. trim B. melt C. drill D. slice

单选题The {{U}}hands{{/U}} of the clock showed that it was time for dinner.

单选题The trumpet was part of the opera orchestra long before it became a standard orchestral instrument.A. majorB. tunefulC. desirableD. regular

单选题The journalist used to drink Diet Coke and tuck in his shirts in order to keep trim.

单选题John is collaborating with Mary in writing an article.

单选题Apple trees need moisture in order to thrive.A. flowerB. flourishC. pollinateD. bend

单选题KidneyDiseaseandHeartDiseaseSpurEachOtherHeartsandkidneys:Ifone'sdiseased,betterkeepacloseeyeontheother.Surprisingnewresearchshowskidneydiseasesomehowspeedsupheartdiseasewellbeforeithasravagedthekidneys.Andperhapsnotsosurprising,doctorshavefinallyproventhatheartdiseasecantriggerkidneydestruction,too.Thework,fromtwostudiesinvolvingover50,000patients,promisestoboosteffortstodiagnosesimmeringkidneydiseaseearlier.Allittakesareurineandbloodteststhatcostlessthan$25,somethingproponentswanttobecomeasroutineascholesterolchecks."Theaveragepatientknowstheircholesterol,"saysDr.PeterMcCullough,preventivemedicinechiefatMichigan'sWilliamBeaumontHospital."Theaveragepatienthasnoideaoftheirkidneyfunction."Chronickidneydisease,orCKD,isaquietepidemic:Manyofthe19millionAmericansestimatedtohaveitdon'tknowtheydo.Thekidneyslosetheirabilitytofilterwasteoutofthebloodstreamsoslowlythatsymptomsaren'tobviousuntiltheorgansareverydamaged.End-stagekidneyfailureisrisingfast,with400,000peoplerequiringdialysisoratransplanttosurvive,atollthathasdoubledineachofthelasttwodecades.AndwhileCKDpatientsoftenareterrifiedofhavingtogoondialysis,thehardtruthisthatmostwilldieofheartdiseasebeforetheirkidneysdisintegratetothatpoint,somethingkidneyspecialistshaverecognizedforseveralyearsbutisn'twidelyknown.Indeed,thenewresearchishighlightedinthismonth'sArchivesofInternalMedicinewithacallfordoctorswhocareforheartpatientstostartrigorouslycheckingoutthekidneys,andforbettercareofearlykidneydiseaseThelinksoundslogical.Afterall,highbloodpressureanddiabetesarechiefriskfactorsforbothchronickidneydiseaseandheartattacks.Butthelinkgoesbeyondthoseriskfactors,stressesMcCullough:Oncethekidneysbegintofail,somethinginturnacceleratesheartdisease,notjustintheobviouslysickorveryold,butatwhathecalls"ashockinglyearlyage."McCulloughandcolleaguestrackedmorethan37,000relativelyyoungpeople—averageage53—whovolunteeredforakidneyscreening.Threemarkersofkidneyfunctionwerechecked:therateatwhichkidneysfilterblood,calledtheGFRorglomerularfiltrationrate;levelsoftheproteinalbuminintheurine;andiftheywereanemic.Theyalsowereaskedaboutpreviouslydiagnosedheartdisease.Theoddsofhavingheartdiseaserosesteadilyaseachofthekidneymarkersworsened.Morestrikingwasthedeathdata.Atthisage,fewdeathsareexpected,andindeedjust191peoplediedduringthestudyperiod.ButthosewhohadbothCKDandknownheartdiseasehadathreefoldincreasedriskofdeathinamereyears,mostlyfromheartproblems."Thisstudyisverymuchawake-upcall."McCulloughsays.

单选题The idea of test-tube babies may make you starry-eyed with delight at the wonders of modern medicine or bleary-eyed with considering the moral/legal implications of starting life in a laboratory. But if you've ever been pregnant(怀孕的)yourself, one thing is certain: You wonder what it's like to carry a test-tube baby. Are these pregnancies normal? Are the babies normal? The earliest answers come from Australia, where a group of medical experts at the Queen Victoria Medical Center in Melbourne have taken a look at the continent's first nine successful test-tube pregnancies. The Australians report that the pregnancies themselves seemed to proceed according to plan, but at birth some unusual trends did show up. Seven of the nine babies turned out to be girls. Six of the nine were delivered by Caesarean section(剖腹产术). And one baby, a twin, was born with a serious heart defect and a few days later developed life-threatening abdominal(腹剖的)problems. What does it all mean? Even the doctors don't know for sure, because the numbers are so small. The proportion of girls to boys is high, but until there are many more test-tube babies, no one will know whether that's pure coincidence(巧合)or something special. The same thing is true of the single heart defect; it usually shows up in only 15 out of 60,000 births in that part of Australia, but the fact that it occurred in one out of nine test-tube babies does not necessarily mean that they are at special risk. One thing the doctors can explain is the high number of Caesareans. The Australian researchers report that they are quite encouraged. All the babies are now making normal progress--even the twin with the birth defects.

单选题Tickets must be purchased two weeks in advance.A. bookedB. boughtC. soldD. obtained

单选题It's beyond {{U}}mortal{{/U}} power to bring a dead man back to life.

单选题Theories of teaching have not been as fully developed as have theories of learning.

单选题Drug Resistance Fades Quickly in Key Aids Drug One of the main weapons to prevent mother-to-child transmission of the AIDS virus during birth is the drug nevirapine. But when nevirapine is used alone just once, HIV starts becoming resistant to it. Research in Botswana shows that the resistance is not long lasting and that this affordable drug does not have to be abandoned forever by infected mothers who have already taken it. International medical guidelines call for pregnant women with advanced HIV to get a combination of AIDS drugs including nevirapine to prevent passing their infection on to their newborns during delivery. But in poor countries, combinations have been expensive and nevirapine has often been used alone, since studies have shown that a single dose can cut the transmission rate in half. The problem is that HIV resistance builds against it quickly when used alone just once because other drugs are not present to kill the virus particles that survive nevirapine. This renders the drug less effective in later combinations for treating women after their baby is born. But the new study from Botswana shows that nevirapine can make a comeback for these women if they wait until the resistance subsides. "The further out you get from that exposure to single dose nevirapine, the less detectable nevirapine resistance is," said Shahin Lockman of the Harvard School of Public Health in Boston. She says waiting period for women who get the single dose of nevirapine at delivery can be as short as six months. "If they started nevirapine-based treatment six or more months after nevirapine exposure, their treatment response was just as good, and really quite high, compared to women who did not have the single dose of nevirapine," she added. "However, the women who started nevirapine-based treatment within six months of that nevirapine exposure were much more likely to experience treatment failure." The study published in the New England Journal of Medicine shows that waiting at least six months means that HIV-positive women are 70 percent more likely to benefit from nevirapine-based drug combinations again than women who get them sooner. An official with the US government health agency that helped fund the study calls it very important. Iynne Mofenson is chief of research on child, adolescent, and maternal AIDS at the US National Institute of Child Health and Human Development. She says the finding supports a World Health Organization (WHO) recommendation restricting a single dose of nevirapine only to pregnant HIV-infected women who are healthy enough to wait six months after childbirth for more nevirapine-based therapy. Otherwise, they should get other drugs during labor. "It shows the importance of screening women for treatment while they are pregnant and putting them on appropriate therapy while they are pregnant to avoid having to start them too soon after they received preventive therapy," she explained. Shahin Lockman in Boston says the problem of nevirapine resistance should diminish now that more and more people are receiving combinations of AIDS drugs under expanded US and international programs to deliver them to Africa and other regions hard hit by the virus.

单选题Exercise Can Replace Insulin for Elderly Diabetics Most older people with so-called type II diabetes could stop taking insulin if they would do brisk exercise for 30 minutes just three times a week, according to new medical research results reported in the Copenhagen newspaper Berlingske Tidende on Monday. Results from tests conducted on diabetics at the Copenhagen Central Hospital Rigshospitalet's Center for Muscle Research showed that physical exercise can boost the body's ability to utilize insulin by 30 percent, the newspaper reported. This is equal tol the effect most elderly diabetics get from their insulin medication today, it said. Researchers had a group of non-diabetic men and a group of men with type It ,all more than 60 years of age, exercise on bicycles six times a week for three months. After the three months the doctors measured how much sugar the test subjects' muscles could utilize as a measure for howwell their insulin worked. Associate Professor Dr. Flemming Dela of the Muscle Research Center said the tests demonstrated that the exercising diabetics had just as high insulin utilization as the healthy on-exercising persons. "This means that the insulin works just as well for both groups. Physical exercise cannot cure people of diabetes, but it can eliminate almost all their symptoms. At the same time it can put off the point at which they have to begin taking insulin or perhaps completely avoid insulin treatment." Dela was quoted as saying. Insulin is a hormone produced by the pancreas, controlling sugar in the body and used against diabetes. Dela said that to achieve the desired effect diabetics need only exercise to the point where they begin to work up a sweat, but that the activity has to be maintained since it wears off after five days without sufficient exercise. Most diabetics realize that they have to watch their diet while remaining unaware of the importance of exercise, Dela added.

单选题Mary looked pale and weary .