单选题Binge eating changes the way the body responds to Leptin(瘦素) , the key appetite-suppressing hormone, say researchers in New York. Their experiments with rats could explain why people who overeat continue to crave food despite ginning weight. As we eat, Leptin levels in our blood gradually rise and suppress the appetite until more energy is needed. Leptin also speeds up the metabolism, so that less food is converted to fat. "The object is to take you back to the original point," says Luciano Rossetti, a diabetes researcher at the Albert Einstein College of Medicine. But a popular theory holds that if Leptin worked too well, it would defeat the purpose of fat, which is to store energy for lean times. Animals that can build up fat reserves when meals abound have a better chance of survival than their skinny companions should famine strike. To understand how Leptin keeps fat in check without preventing it from accumulating vital reserves, Rossetti and his colleagues created feast and famine conditions for two groups of rats. Over three days, members of one group could eat all they wanted, while the other rats were kept on a restricted diet. Normally, Leptin moderates its own production slightly by reducing the activity of the Leptin gene in fat cells. In the rats with a skimpy diet, however, an injection of Leptin into the bloodstream hardly reduced the activity of the gene in fat tissue at all. By contrast, in the overeaters the injection cut Leptin gene activity in half. That came as a surprise, says Rossetti, as it means the overeaters would counteract an appetite-suppressing boost in Leptin, such as that caused by a meal, more quickly than the dieting rats. One possible outcome is that the guzzlers would be ready to eat again sooner. Similar mechanisms in humans may have given them an evolutionary advantage in prehistoric times, when food was probably scarce. But today it may lead to a spiral of overeating, Rossetti says, with each binge making a person more prone to the next: "People go on numerous circles of increased feeding." Since the tendency toward obesity varies from person to person, Rossetti plans to look for differences in the Leptin binge response in lean and fat strains of rats. Jeffrey Flier, a Leptin researcher at Beth Israel Hospital in Boston, says it would also be important to check whether moderately overweight people fail to increase the activity of their Leptin gene when they overeat. Without such experiments, he says, it's hard to conclude that Rossetti has discovered why inflated waist lines are so common. "At this stage, it's still purely hypothetical."

单选题OFF THE CHANNEL ISLANDS, California—Large numbers of giant endangered blue whales have gathered offshore attracting dozens of marine biologists who want to know why. Scientists aboard six ships from the National Oceanic and Atmospheric Administration and other experts are working on a three-week project this summer to tag and track the whales electronically. Three blue whales were tagged and followed last week, but scientists have seen many more. " This is cetascean soup out here," said Fred Benko, owner of a private charter boat that shuttles scientists to and from their research area. The mammals, some up to 30 metres long, have congregated about 30 kilometres west of the Channel Islands, which are about 40 kilometres southwest of Santa Barbara and 120 kilometres northwest of Los Angeles. Scientists first noticed the increase in blue whales in local waters in 1991, and a 1993 study indicated about 2,000 blue whales along the California coast. Preliminary research suggests that the Channel Islands National Marine Sanctuary contains the most concentrated blue whale population in the world. The US Government has listed the animals as endangered since 1966, victims of the over zealous whaling industry in the first half of the century. Scientists believe there once were 400,000 blue whales roaming the world' s oceans, but now only about 12,000. The blue whales feed on krill, bright red crustaceans similar to shrimp. But since the Channel Islands are hardly the only place where krill thrive, researchers wonder what else might be drawing the whales to the area. To tag the whales, scientists use a crossbow to fire a dart into blubber on the creature' s back. A computer records the depth and length of every dive the whale takes. " It' s important for me that people know that they have a treasure out here," said sanctuary Manager Ed Cassano. " This is something everybody should be proud of. It' s the jewel in the crown. "

单选题In recent years there has been an increasing number of large oil spills. These spills, some of which have occurred directly at the site of extraction and others during transportation, have had in adverse effect on marine organisms. Because of the importance of these organisms in the life cycle, research has been carried out in order to identify more accurately the reactions of these organisms to oil. A recent study has revealed that it is essential to understand that there is not one but rather, at least four possible ways in which oil can affect an organism. First, as a result of an organism"s ingestion of oil, direct lethal toxicity, that is, death by poisoning can occur. However, in cases where the effect is less extreme, sub-lethal toxicity occurs. While cellular and physiological processes are involved in both cases in the latter, the organism continues to survive. Second, in some cases, oil forms a covering on the organism. This covering, referred to as coating, can result in smothering, that is, death of the organism due to lack of air. In instances where the effects of coating are less severe, interference with movement and loss of insulated properties of feathers or fur may occur. The third effect of oil on marine organisms is the tainting or contamination of edible organisms. This results from the incorporation of hydrocarbons into the organism, thus making it unfit for human consumption. The final effect which this study has revealed is that of habitual changes. The alterations in the physical and chemical environment brought about by oil spills result in a change in the species composition of a region. The implications of this must recent study are far-reaching. An oil spill in a particular region could critically upset the balance of nature, the total effect only becoming apparent after many years.

单选题In a poor, inland, gang-infested part of Los Angeles, there is a clinic for people with type I diabetes. As part of the country health care system, it serves persons who have fallen through all other safety-net options, the poorest of the poor. Although type II diabetes is rampant in this part of town, type I diabetes exists as well. Yet these latter individuals generally lack access to any specialty care—a type of treatment they desperately need due to a complexity of dealing with type 1 diabetes in the setting of poverty and psychosocial stress. The Type I Clinic meets one morning per week and is staffed by four endocrinology fellows and a diabetologist, often me. I have the unique perspective of working part of the time in a county setting and the other part of the time in a clinic for people with health insurance, in Beverly Hills. I know what is possible in the treatment of type 1 diabetes. East Los Angeles teaches me what happens when access to care is not available. Most of our patients, in their 20s and 30s and 40s, already have complications of their diabetes; many near end stage. Concepts about maintaining near-normal blood glucose levels often miss their mark—lack of education or money or motivation or factors I can't even imagine make the necessity of a patient acting as his or her own exogenous pancreas nearly impossible, especially when there are acute consequences to hypoglycemia and few to moderate hyperglycemia. Historically, in spite of these barriers, we persisted and thought we made a difference. Often, teaching simple carbohydrate counting or switching therapy to long-acting insulin improved patients control and their quality of life. The fellows felt they made a positive impact in the health of their patients. Driving home I would be encouraged by what we had accomplished, although saddened by the severity of the complications suffered by many of our patients. Yet everything changed with the recession of 2008. In Beverly Hills I heard a lot about the demise of the financial markets. Patients of mine had invested with Bermie Madoff. Some, once billionaires, were now millionaires. Personal assistants and housekeepers were laid off, vacation homes were put on the market, and parties became less lavish. But all still live in safe, clean homes, wear designer clothes, and eat high-quality food. The landscape is very different for many of my East LA patterns. The temporary, part-time jobs they had cobbled together to keep food on the table and pay for housing are gone. I — naively — didn't realize how much worse poverty could get. But now many of our patients are young without food and are becoming homeless. One young man, a college student trying to work his way out of poverty by going to school, lost his job and is living in his car. He is still taking classes but is unable to afford more than a dollar meal from a fast-food restaurant once every day or two. Management of his diabetes involves simply keeping him alive with his erratic, poor eating habit.

单选题Do you believe that only boys do well in science? Does it seem to you that girls have better vocabularies than boys? In your opinion, are boys better at building things? If your answer to each of those questions is "Yes", you are right according to an article in Current Science. There are exceptions, but here are the facts. On the average, males score higher on tests that measure mathematical reasoning, mechanical ability, and problem-solving skills. Females show superior ability in tests measuring vocabulary, spelling, and memory. But these difference will probably not always exist. In the future, a person"s abilities may not be determined by sex. As one scientist says, "Nothing is impossible for a person to be or do." In several recent studies, young babies have been observed and tested to discover how different abilities are developed. A scientific team headed by Jerome Kagan, a psychologist at Harvard University, is studying the thinking ability of children 9 months old. The test is a simple one. The baby, while seated on its mother"s lap, watches a "show" on a theater stage. In act 1 of the show, an orange-colored block is lifted from a blue box and moved slowly across the stage. Then it is returned to the box. This is repeated six times. Act 2 is similar, except that the orange block is smaller. Baby boys do not seem to notice the difference in the size of the block, but girls immediately become excited and begin to make noises that sound like language. They seem to be trying to talk. It is known that bones, muscles, and nerves develop faster in baby girls. Usually, too, baby girls talk at an earlier age than boys do. Scientists think there is a physical reason for this. They believe that the nerve endings in the left side of the brain develop faster in girls than in boys. And it is this side of the brain that strongly influences an individual"s ability to use words, to spell, and to remember things. By the time they start to school, therefore, little girls have an advantage that boys do not have. Girls are physically more ready to remember facts, to spell, and to read. These, of course, are skills that are important in elementary school. But what have the boys been doing in the years before starting school? They have been developing something called aggression. An aggressive person has courage and energy. He feels strong and independent. He is often the first one to start a fight.

单选题Can the internet help patients jump the line at the doctor"s office? The Silicon Valley Employers Forum, a sophisticated group of technology companies, is launching a pilot program to test online "virtual visits" between doctors at three big local medical groups and about 8,000 employees and their families. The six employers taking part in the Silicon Valley initiative, including heavy hitters such as Oracle and Cisco Systems, hope that online visits will means employees won"t have to skip work to tend to minor ailment or to follow up on chronic conditions. "With our long commutes and traffic, driving 40 miles to your doctor in your hometown can be a big chunk of time," says Cindy Conway, benefits director at Cadence Design Systems, one of the participating companies. Doctors aren"t clamoring to chart with patients online for free; they spend enough unpaid time on the phone. Only 1 in 5 has ever E-mailed a patient, and just 9 percent are interested in doing so, according to the research firm Cyber Dialogue. "We are not stupid," says Stirling Somers, executive director of the Silicon Valley Employers group. "Doctors getting paid is a critical piece in getting this to work." In the pilot program, physicians will get $ 20 per online consultation; abut what they get for a simple office visit. Doctors also fear they"ll be swamped by rambling E-mails that tell everything but what"s needed to make a diagnosis. So the new program will use technology supplied by Healinx, an Alameda, Calif, -based start-up. Healinx"s "Smart Symptom Wizard" questions patients and turns answers into a succinct message. The company has online dialogues for 60 common conditions. The doctor can then diagnose the problem and outline a treatment plan, which could include E-mailing a prescription or a face to face visit. Can E-mail replace the doctor"s office? Many conditions, such as persistent cough, require a stethoscope to discover what"s wrong—and to avoid a malpractice suit. Even Larry Bonham, head of one of the doctor"s groups in the pilot, believes the virtual doctor"s visits offer a "very narrow" sliver of service between phone calls to an advice nurse and a visit to the clinic. The pilot program, set to end in nine months, also hopes to determine whether online visits will boost worker productivity enough to offset the cost of the service. So far, the internet"s record in the health field has been underwhelming. The experiment is "a huge roll of the dice for Healinx," notes Michael Barrett, and analyst at internet consulting from Forester Research. If the "Web visits" succeed, expect some HMOs(Health Maintenance Organizations)to pay for online visits. If doctors, employers, and patients aren"t satisfied, figure on one more E-health start-up to stand down.

单选题I make my way down the three chilly blocks to an old diner on Commercial Street. I am meeting a new friend for lunch. I" ve never been here before; this is not my part of town. And so I arrive early, to sit in an old wooden booth and learn what I can about the place. They call it Katie" s Kitchen. One hundred years ago, it was a bar. The barstools remain, but through community donations, it" s now a respectable restaurant. The hostess, casher, and waiters are residents of a nearby hotel for the transient and unemployed and work here to gain dignity and job skills. Both the hotel and restaurant are run by Sister L, a nun with a heart and a great deal of business sense. My new friend arrives. He works down the street, in a clinic for indigent(贫穷的)persons; he knows these people. The workers and many of the clients seem to know him too, for I see warmth and proud smiles on their faces as he greets them. Behind him, a few nameless souls wander in from the street in a swirl of December wind. I focus on our waitress. A pretty girl of perhaps 18 years, she is all smiles and grace. I wonder for a moment why she" s here—what her story is; what her dreams are; whether she is raising children on her own. But I cannot hold the thought, for she reminds me of another waitress at my favorite coffee shop—a college student with a bright future. Some time later, I finish my soup and sandwich—a good meal made better because of the smile of the girl who served it. I wipe my mouth and go to pay. Eight dollars and sixty-four cents, for two. To our embarrassment, my friend and I discover that neither of us has cash, and my credit card is not good here. We sheepishly approach Sister L, who smiles and takes my bill. "It" s o-kay," she says. "We"ll buy your lunch. It"ll be our pleasure. Slowly, I leave the world of the diner. Back at the hospital where I work, my boss laments our financial woes. "We" re really tight," he says. "The executive committee tells me we may not even have enough money to build the new critical care wing this year. " He frowns, hesitates, then adds, " It" s flu season, though, and perhaps by seeing patients in person rather than treating so many over the phone, we" 11 recoup some of our losses. " It" s budget time, and I know that this means our gratis(免费的)fitness center memberships may be cancelled. We"re in a tough bind. Three streets away, a tattered man in a throwaway overcoat sits shivering in the diner. Sister L slowly fills his cup full of hot coffee. Holding the cup with trembling hands, he stares deeply into its dark center. There is healing in its rising steam.

单选题A study has shown that fitness is the key【C1】______ long life, irrespective of body shape or even smoking habits. Researchers discovered that people【C2】______ exercise live longer than those do not,【C3】______ they are overweight and smoke. The study found that the least fit of the 6 000 middle-aged men in the study were five times【C4】______ to die within six years of the start of the research than the【C5】______ . This was true whether or not the men had heart problems, smoked or were overweight. Scientists concluded that it was better to be fat and【C6】______ than skinny and sedentary(久坐的). Dr. Ken Cooper, a fitness expert, said, "You are better off smoking a packet of cigarettes a day and【C7】______ regularly than being a non-smoker and sedentary." Although he adds, "But don't misunderstand me. I am not endorsing smoking. I am trying to tell you how dangerous it is to be sedentary."【C8】______ , the study appears to fly in the face of research last year which concluded that more than 30 000 people die prematurely every year in Britain from illnesses caused by being overweight. The British Government is putting pressure on manufacturers【C9】______ high levels of sugar in food and to restrict the hard-sell of junk food to children in order to improve the nation's health. But the new study suggests the Government【C10】______ more people to exercise.

单选题Already lasers can obliterate skin blemishes, topically applied drugs can smooth facial lines and injected agents can remove deep wrinkles. Future products will be faster, better and longer lasting. "New substances will be developed by entrepreneurs," says Brian Mayou, an aesthetic plastic surgeon, "that will be more successful than liquid silicone that we use today to eradicate wrinkles." The next major breakthrough, says Mel Braham, plastic surgeon and chief executive of the Harley Medical Group, will be laser treatment that needs no recovery period. Micholas Lowe, clinical professor of dermatology at the University of Los Angeles, adds: "There will be more efficient anti-oxidants to help reduce sun damage and aging. There will also be substances that increase the production of new collagen and elastic tissue to maintain the elasticity of youthful skin." Lee Shreider, a research cosmetic chemist, says that we may be able to look better without any kind of operation as semi-permanent make-up gets better. "Crooked noses will be improved by effectively sealing on shaded colors that either enhance or subdue areas of the face. We will be able to straighten eyebrows and lips making the face more symmetrical — which remains one of the keys to beauty — and even close blocked pores with permanent, custom-designed foundation." The development of the safe sun tan is a potential gold mine. Being researched at the University of Arizona, but a long way from reality, is the injectable tan. Professor Lowe is optimistic: "There will almost certainly be a safe way of developing a sunless tan that protects against sun damage. In animal research, we"ve applied creams to guinea pigs that can actually "turn on" some of the genes that produce pigmentation without any sunlight exposure."

单选题Some problems can be readily identified simply by looking around. These problems concern the pollution of our environment by technology as a result of sudden upsets in the physical, economic and social balance. The most obvious of these are the general pollution of our physical environment and the destruction of irreplaceable natural resources. Not so obvious as these, but just as painfully significant to some, are the disappearing and changing of jobs which overnight often create large groups of jobless citizens. Can technology be used to undo what it has done, replace what it has destroyed or substitute for what it has caused to disappear? No one knows. Many wonder whether or not all of the sources of pollution have yet been identified, whether or not they are being arrested and whether or not they will be prevented from recurring. Another set of problems relates to what technological advancement has done to the quality of life. An improved social life has not been unfortunately, either the goal or the chief beneficiary of technological change. Rather, any improvements that have occurred have been more accidental than intended. Too much has happened too fast. The changes demanded of marriage and family relationships remain largely unexamined. It is often a matter of " put up or shut up " , and a person has to a-dapt his life-style to ever-changing conditions with little time for choice. The "no-move-no-advancement" type is an example of one such problem. Many people are coming to think that the reward is simply not worthy the struggle, and they are taking jobs with less responsibility and lower pay.

单选题Cardiologists have pioneered the world's first non-surgical bypass operation to turn a vein into an artery using a new technique to divert blood flow in a man with severe heart disease. The keyhole procedure, which avoids the extensive invasive surgery of a conventional bypass, will offer hope to ten of thousands of people at risk from heart attacks. Coronary heart disease, where the arteries are progressively silted up with fatty deposits, is responsible in a major industrial country like Britain for more than 160, 000 deaths each year. Although major heart surgery is becoming commonplace, with more than 28, 000 bypass operations in the UK annually, it is traumatic for patients and involves a long recovery period. The new technique was carried out by an international team of doctors who performed the non-invasive surgery on a 53-year-old German patient. According to a special report in Circulation, journal of the American Heart Association, cardiologists developed a special catheter which was inserted into one of his leg arteries, threaded up through the aorta to the top of the diseased artery, which was the only part still open and receiving blood. Then, guided by ultrasound, a physician pushed a needle from inside the catheter through the artery wall and into the adjacent vein. A thin, flexible wire was threaded through the needle and the needle and catheter were withdrawn, leaving the wire behind and a small angioplasty balloon, which was used to widen the cannel. Finally, the vein was blocked of just above the new channel allowing blood from the artery to be re-routed down the vein. After the procedure, the vein effectively became an artery, carrying blood in the reverse direction from the previous way, and feeding the starved heart tissue with oxygen. Dr. Stephen Oesterle, who led the team, said: "This milestone marks the first coronary artery bypass performed with a catheter. The technology offers a realistic hope for truly minimally invasive bypass procedures in the future. One of the most invasive things you can do in medicine is coronary artery bypass surgery. Our ultimate goal is to replace traditional coronary artery bypass with a procedure that does not require surgery. " Dr. Oesterle is director of cardiology at Massachusetts General Hospital and associated professor of medicine at Harvard Medical School in Boston, Melanie Raddon, cardia nurse at the British Heart Foundation, said it was likely to be many years before the procedure was routinely used in hospitals.

单选题When I was first diagnosed as diabetic in 1962, it was almost impossible for a diabetic on insulin to get life insurance, except at the most abnormal, penal rates. Today, we can obtain insurance at almost normal premiums, even though insurance companies are not in the habit of throwing their money away! They can see the improvement. Today we, the diabetic community, feel more in control and know that we can have a normal life. We can fit our diabetes into our lives and not fit our lives into the diabetes. This tremendous achievement is one result of the improved health technologies which are of benefit to all. Glucose test strips are simple and inexpensive, yet to me they are the elixir of life. Because thanks to them I can monitor my own blood sugar, and I can vary my diet and dietary requirements accordingly. This is why, to the diabetic on insulin, the availability of blood glucose monitoring equipment has been almost as important as the discovery of insulin. We know what the unavailability of such basic equipment may mean in terms of quality of life. I was very fortunate to be able to visit Romania immediately after the 1989 revolution to see for myself the problems there. Although they had excellent, dedicated doctors and health workers, I was horrified to see the number of patients who had suffered amputations, who were blind, who suffered other complications from diabetes and who clearly were no longer able to perform a useful job or enjoy a full and happy life-style. How can this be today? Those who are governing us should be asking this question themselves. 1 refer not only to people from central and eastern Europe, but also to those from sophisticated "Western" economies. I understand that in one of the latter countries(perhaps the most sophisticated and the wealthiest)there is a problem in obtaining free distribution of glucose strips because the health insurance companies say they are too expensive. Too expensive to whom is the right question to ask. Improved and affordable health procedures can work wonders everywhere, and there is still a lot to do if we want this simple fact to be acknowledged.

单选题The more medical science discovers about the complex interplay between nature and nurture, genetics and environment, the larger the role family history appears to play in disease. Last month's announcement that most of the 30, 000-plus genes in the human genome had been identified is likely to prompt a better understanding of family-related illness and new gene-based treatments. But until such treatments are available, people with a family history of certain diseases need to be watchful. They also need to remember that for most diseases, family history is not destiny. If you have what's known as a first-degree relative — a parent or sibling — who has been diagnosed with an illness, say, cancer, then your risk of developing the same illness rises. Having two affected first-degree relatives, or family members across generations — your mother and your grandmother — increases your risk further. "If the illness is occurring in multiple, close relatives, at younger ages than is typical for that disease, and over more than one generation, you have a truly problematic family history, says Robin Bennett of the Medical Genetics Clinic at the University of Washington Medical Center. In families afflicted with certain inherited disorders such as sickle cell anemia and cystic fibrosis, genes alone seem to determine who gets sick. But for most people, family history, lifestyle, and environment all influence which illnesses they develop, and at what age. Even if you have strong family history of, say, breast cancer, heart disease, or diabetes, taking advantage of the proven screening tests and treatments and changing your lifestyle may tip the odds back in your favor. Nearly everyone faces some kind of genetic risk. By comparing the health histories of twins with same genetic makeup, scientists have estimated the contribution genes make to trait like weight, cholesterol level, and blood pressure. Kenneth Kendler, a professor of psychiatry and genetics at the medical College of Virginia, has found that genes contribute heavily to some mental disorders, too. "We're pretty sure that with schizophrenia and bipolar disorders, 70 or 80 percent is inherited. Alcohol and drug dependence, 50 to 60 percent. Depression, 35 to 40 percent, . " Even so, he adds, "The strongest predictor of major depression is still your life experience. There aren't genes that make you depressed; there are genes that make you vulnerable to depression. "

单选题During the past 30 years or so, health care has increasingly become a form of business. In addition, the environment surrounding health care has been greatly altered by the advent of more sophisticated medical technologies and increased specialization. It is no longer true to say that doctors regard their profession as a sacred calling, and while the doctor-patient relationship still remains, it is not the relationship based solely on trust which it used to be. Of course there are many doctors who have endeavored to increase the transparency of their behavior as medical professionals, and patients can receive effective treatment when such doctors work closely together and share notes. An example of such cooperation can be found in the field of remote health care, which has been introduced on an experimental basis in several regions. Since most medical specialists live in cities, patients who live in the country have to travel a long distance to consult a specialist. This is especially hard on the elderly, both financially and physically. Through a computer network, patients who live in the country can consult a medical specialist in the city, tell him their symptoms, and receive advice without the need for a journey to the specialist's office. Also, with several doctors being assigned to a single patient, the transparency of each doctor's behavior is further ensured. On the other hand, however, it is also true that remote health consultation is not generally regarded as a form of medical treatment. For any sort of consultation to be regarded as medical treatment, most people feel that the patient must actually visit the doctor, and undergo an examination by the doctor in person. Remote health care is essentially a means for doctors to work as a team. In order for this to be practicable, it is important to establish a system whereby financial support can be extended to a doctor who, as a member of a medical team, provides only information. Establishment of such a system will further advance the cause of" free access to information" in the health care field.

单选题Publishing in scientific journals is the most common and powerful means to disseminate new research findings. Visibility and credibility in the scientific world require publishing in journals that are included in global indexing databases such as those of the Institute for Scientific Information (ISI). Most scientists in developing countries remain at the periphery of this critical communication process, exacerbating the low international recognition and impact of their accomplishments. For science to become maximally influential and productive across the globe, this needs to change. The economy of electronic publication, open access, and property rights fuel current academic and policy debates about scientific publishing in the industrialized world. The concerns in the developing world (with few ISI-indexed journals) focus on more fundamental questions, such as sustaining local research activity and achieving the appropriate global reach of its science activities. The essence of the African situation is captured by R. J. W. Tijssen's analysis of publications by African authors, which was based not only on data from ISI indexing databases, but also on publications not indexed in this system. Surprisingly, half of the South African citations in the indexed ISI literature are to articles in nonindexed, locally published journals. Also, several nonindexed local journals are cited in the ISI system at about the same rate as are indexed journals. The share of indexed articles with at least one author with an Africa address remains steady at about 1%. About half of the ISI-indexed papers with at least one author with an African address have non-African partners outside of the continent. These figures vary, country by country, sometimes in surprising ways. For example, 85% of the papers published from Mali or Gabon involve collaborations on other continents, versus 39% and 29%, respectively, for South Africa and Egypt, the continent's leading research producers. Thus, much of the African research system is now highly dependent on collaborations. How can the global reach and potential impact of scientific research in Africa and other developing countries be optimized? Of primary importance is boosting the quality and quantity of work that is locally published, through measures including review of submissions by peers research opportunities. A proliferation of journals, short-lived publications, print-only journals, and poor distribution constitutes a picture that must change. A nationally organized project can probably make the biggest difference, with investment by government and research-support agencies, as well as wide participation by local and regional scientific communities.

单选题For several years, scientists have been testing a substance called interferon(干扰素), a potential wonder drug that is proving to be effective in treating a variety of ailments, including virus infections, bacteria infections, and tumors. To date, the new drug has provoked no negative reaction of sufficient significance to discourage its use. But in spite of its success, last year only one gram was produced in the entire world. The reason for the scarcity lies in the structure of interferon. A species of specific protein, the interferon produced from one animal species cannot be used in treating another animal species. In other words, to treat human beings, only interferon produced by human beings may be used. The drug is produced by infecting white blood cells with a virus. Fortunately, it is so powerful that the amount given each patient per injection is very small. Unlike antibiotics, interferon does not attack germs directly. Instead, it makes unaffected cells resistant to infection, and prevents the multiplication of viruses within cells. As you might conclude, one of the most dramatic uses of interferon has been in the treatment of cancer. Dr. Hans Strander, research physician at Sweden" s famous Karolinska Institute, has treated more than one hundred cancer patients with the new drug. Among a group of selected patients who has undergone surgical procedures for advanced cancer, half were given interferon. The survival rate over a three-year period was 70 percent among those who were treated with interferon as compared with only 10 to 30 percent among those who have received the conventional treatments. In the United States, a large-scale project supported by the American Cancer Society is now underway. If the experiment is successful, interferon could become one of the greatest medical discoveries of our time.

单选题It" s becoming something of a joke along the Maine-Canada border. So many busloads of retired people crisscross the line looking for affordable drugs that the roadside stands should advertise, "Lobsters. Blueberries. Lipitor. Coumalin. " Except, of course, that such a market in prescription drugs would be illegal. These senior long-distance shopping sprees fall in a legal gray zone. But as long as people cross the border with prescriptions from a physician and have them filled for no more than a three-month supply for personal use, customs and other federal officials leave them alone. The trip might be tiring, but people can save an average of 60 percent on the cost of their prescription drugs. For some, that" s the difference between taking the drugs or doing without. " The last bus trip I was on six months ago had 25 seniors," says Chellie Pingree, former Maine state senator and now president of Common Cause. "Those 25 people saved $ 19,000 on their supplies of drugs. " Pingree sponsored Maine RX, which authorizes a discounted price on drugs for Maine residents who lack insurance coverage. The law was challenged by drug companies but recently upheld by the U. S. Supreme Court. It hasn" t yet taken effect. Figuring out ways to spend less on prescription drugs has become a multifaceted national movement of consumers, largely senior citizens. The prescription drug bill in America is $ 160 billion annually, and people over 65 fill five times as many prescriptions as working Americans on average. " But they do it on health benefits that are half as good and on incomes that are half as large," says Richard Evans, senior analyst at Sanford C. Bernstein, an investment research firm. What" s more, seniors account for 20 percent of the voting public. It" s little wonder that the May 19 Supreme Court ruling got the attention of drug manufacturers and politicians across the country. The often-over-looked state of 1.3 million tucked in the northeast corner of the country became David to the pharmaceutical industry" s Goliath. The face-off began three years ago when state legislators like Pingree began questioning why Maine" s elderly population had to take all those bus trips.

单选题We are all members of a culture. How we interpret the reality around us, what we consider to be reasonable statements and behavior, and what we believe to be health and illness all stem from the culture we share with some people and not with others. Those whose cultural experiences differ from our own will also differ in their beliefs and interpretations of reality. We are all rooted in an ethnic group as well, even if this group is simply the so-called " majority" of white, middle-class, protestant heritage. The degree to which we identify with an ethnic past will vary according to the strength with which family tradition has maintained that identity, and to the degree that the family chooses to assimilate into the larger society. The extent of an individual" s or a family" s identification with an ethnic heritage is as important as the specific features of that heritage. American society is ethnically and culturally diverse, and community health nurses will find themselves practicing in communities that reflect this diversity. A particular family or a whole community may belong to an ethnic or cultural group very different from the nurse" s own. Those community health nurses who are most sensitive to variations in clients" beliefs and behaviors will be most effective in promoting their wellness. Community health nurses can achieve this sensitivity by examining their own culture in order to understand how it colors their world view and their interactions with individuals, families, and communities. Recognizing that clients are individuals as well as members of a larger culture, nurses will reject stereotypical views of clients" ethnic groups that can impede communication and diminish their effectiveness. Indeed, culture mediates all social encounters, including those between nurse and client, and its study can enhance the effectiveness of health care services.

单选题By the year 2020 more than 1000 million of the people in the world will be over 60 years old, and more than two-thirds of them will be living in developing countries. In the early 1950s, average life expectancy at birth was 47 years worldwide. In 1995 it was more than 65 years, and in several countries it was almost 80. Change of this magnitude amounts to a revolution in both demographic and cultural terms. It has been brought about partly by socioeconomic factors, such as better nutrition and living conditions, and partly by improvements in health care. Not only do we have drugs and treatments to cure diseases that in the past led to premature death, we also have vaccines to prevent many of these diseases, and in some cases even to eradicate them. Furthermore, a larger proportion of the world" s population has ready access to effective medicine. If the main public health challenge of this century has been survival, that of the next will be quality of life. With the steadily rising number of children who reach adulthood and adults who reach old age, the most pressing concern becomes that of ensuring that all of them enjoy the highest attainable level of well-being. To help promote a global response to this major societal concern. WHO launched a new programme on ageing and health in 1995. Its perspectives and activities are described in this issue of World Health, together with some of the ways in which society is responding to this new phenomenon of a growing elderly population. Health is generally felt to be of paramount importance for the quality of life, especially in old age, when physiological and other difficulties tend to accumulate and the end of life approaches. There are many more ways of protecting and improving health than people generally realize, and these articles provide valuable insights into the possibilities that exist.

单选题It used to be so straightforward. A team of researchers working together in the laboratory would submit the results of their research to a journal. A journal editor would then remove the authors" names and affiliations from the paper and send it to their peers for review. Depending on the comments received, the editor would accept the paper for publication or decline it. Copyright rested with the journal publisher, and researchers seeking knowledge of the results would have to subscribe to the journal. The Internet-and pressure from funding agencies, who are questioning why commercial publishers are making money from government-funded research by restricting access to it-is making access to scientific results a reality. The Organization for Economic Co-operation and Development(OECD)has just issued a report describing the far-reaching consequences of this. The report, by John Houghton of Victoria University in Australia and Graham Vickery of the OECD, makes heavy reading for publishers who have, so far, made handsome profits. But it goes further than that. It signals a change in what has, until now, been a key element of scientific endeavor. The value of knowledge and the return on the public investment in research depends, in part, upon wide distribution and ready access. It is big business. In America, the core scientific publishing market is estimated at between $7 billion and $11 billion. The International Association of Scientific, Technical and Medical Publishers say that there are more than 2,000 publishers worldwide specializing in these subjects. They publish more than 1.2 million articles each year in some 16,000 journals. This is now changing. According to the OECD report, some 75% of scholarly journals are now online. Entirely new business models are emerging; three main ones were identified by the report"s authors. There is the so-called big deal, where institutional subscribers pay for access to a collection of online journal titles through site-licensing agreements. There is open-access publishing, typically supported by asking the author(or his employer)to pay for the paper to be published. Finally, there are open-access archives, where organizations such as universities or international laboratories support institutional repositories. Other models exist that are hybrids of these three, such as delayed open-access, where journals allow only subscribers to read a paper for the first six months, before making it freely available to everyone who wishes to see it. All this could change the traditional form of the peer-review process, at least for the publication of papers.