单选题When Paul met Clara again 20 years later, he decided

单选题It is postulated that a cure for the disease will have been found by the year 2000.A. challengedB. assumedC. deductedD. decreed

单选题With a new Administration promising much needed reform in the way health care is accessed, delivered and reimbursed, legislators, health officials, doctors and patients see this as a rare opportunity, a sweet spot in which national need could meet national will and we could actually fix a system that seems to be costing us more and more but delivering less and less. The improvements can't come too soon. In spite of our gleaming hospitals and cutting - edge technology that can detect the tiniest tumors and repair the most complex organ, on some basic health measures the U. S. is starting to fall behind--far behind. What does the author think of the present health - care system?A. SatisfactoryB. DissatisfactoryC. EfficientD. Hopeless.

单选题If we leave now, we should miss the traffic.

单选题His sole {{U}}motive{{/U}} was to make her happy. A. aim B. argument C. capability D. pursuit

单选题.It is laid down in the regulations that all members must carry their membership cards at all times.

单选题 下面的短文有15处空白，请根据短文内容为每处空白确定1个最佳选项。 {{B}}A Health Profile (概貌){{/B}} A health profile is, a portrait of all of the factors that influence your health. To draw your health pro- file, you will{{U}} (51) {{/U}}what diseases run in your family, what health hazards you may be exposed to{{U}}(52) {{/U}}work, how your daily{{U}} (53) {{/U}}compares to the recommended standards, how much time per week you{{U}} (54) {{/U}}exercising and what type of exercise you engage{{U}} (55) {{/U}}, how stressful your work and family environments are, what kinds of illnesses you get regularly, and{{U}} (56) {{/U}}or not you have any one Of a number of. addictions.{{U}} (57) {{/U}}this portrait, you should have a checkup to determine how your blood, heart, and lungs are functioning. This checkup will serve{{U}} (58) {{/U}}a baseline, to which you can then compare later tests. {{U}}(59) {{/U}}this profile is thoroughly drawn, you can begin to think about setting health priorities based{{U}} (60) {{/U}}your particular portrait. For example, if you drink two martinis (马提尼酒) every evening, have a high—stress{{U}} (61) {{/U}}, are overweight, smoke a pack of cigarettes a day, and use marijuana (大麻烟) occasionally on weekends, you should quit smoking first, followed{{U}} (62) {{/U}}losing the excess weight, reducing the stress of your job, giving up your marihuana habit, and then finally giving some{{U}} (63) {{/U}}to those martinis if you, want to prevent first cancer, and then heart disease. Even for the youthful working person who has never been sick a day in his life, who is{{U}} (64) {{/U}}excellent health, a good look at all health habits and at work and home environments any suggest changes that will{{U}} (65) {{/U}}him in the future.

单选题The Weaver Ants in Africa The humble but industrious ant has long served as a metaphor for the economic virtues of simplicity, parsimony and diligence. But in the case of weaver ants in Africa, this description may be more than just a metaphor. According to Paul van Mele of the Consultative Group on International Agricultural Research and his colleagues, African mango farmers could increase their harvests by as much as two-thirds with the help of these doughty insects. Mangoes in Africa, as elsewhere, often fall prey to fruit flies, which destroy about 40% of the continent"s crop. In fact, fruit flies are so common in African mangoes that America has banned their import altogether, to protect its own orchards. African farmers, meanwhile, have few practical means to defend their fruit. Chemical pesticides are expensive. And even for those who can afford them they are not that effective since, by the time a farmer spots an infestation, it is too late to spray. Added to that, spraying tall trees is a much more complicated and unhealthy business than treating low-growing fruit and vegetables. Agricultural scientists have also looked at controlling fruit flies with parasitic wasps. But the most common ones kill off only about one fly in 20, leaving plenty of survivors to go on the rampage. Lethal traps baited with fly-attracting pheromones are another option. But they, too, are expensive. Moreover, all these methods require farmers to detect the presence of fruit flies, and to identify them as the main threat to their crop—no mean feat when most of the action is taking place in dense, leafy canopies ten metres off the ground. Instead, most farmers simply harvest their fruit early, when it is not yet fully ripe. This makes it less vulnerable to the flies, but also less valuable. Farmers whose trees are teeming with weaver ants, however, do not need to bother with any of this. In a survey of several orchards in Benin, Dr van Mele and his colleagues found an average of less than one fruit-fly pupa in each batch of 30 mangoes from trees where weaver ants were abundant, but an average of 77 pupae in batches from trees without weaver ants. The weaver ants, it turns out, are very thorough about hunting down and eating fruit flies, as well as a host of other pests. The only drawback is the ants" painful bite, which can be avoided by harvesting fruit with poles, rather than climbing trees. Weaver ants have been used for pest control in China and other Asian countries for centuries. The practice has also been adopted in Australia. But Dr van Mele argues that it is particularly suited to Africa since weaver ants are endemic to the mango—growing regions of the continent, and little training or capital is needed to put them to work. All you need do is locate a suitable nest and run string from it to the trees you wish to protect. The ants will then quickly find their way to the target. Teaching a group of farmers in Burkina Faso to use weaver ants in this way took just a day. Those farmers no longer use pesticides to control fruit flies, and so are able to market their mangoes as organic to eager European consumers, vastly increasing their income. The ants, so to speak, are on the march.

单选题Once-daily Pill Could Simplify HIV Treatment Bristol-Myers Myers Squibb and Gilead Sciences have combined many HIV drugs into a single pill. Sometimes the best medicine is more than one kind of medicine. Malaria, tuberculosis and HIV/AIDS, for example, are all treated with (51) of drugs. But that can mean a lot of pills to take. It would be (52) if drug companies combined all the medicines into a single pill, taken just once a day. Now, two companies say they have done that for people just (53) treatment for HIV, the virus that causes AIDS. The companies are Bristol-Myers Squibb and Gilead Sciences. They have (54) a single pill that combines three drugs currently on the market. Bristol-Myers Squibb sells one of them (55) the name of Sustiva. Gilead combined the (56) , Emtriva and Viread, into a single pill in two thousand four. Combining drugs involves more than (57) issues. It also involves issues of competition (58) the drugs are made by different companies. The new once-daily pill is the result of (59) is described as the first joint venture agreement of its kind in the treatment of HIV. In January the New England Journal of Medicine published a study of the new pill. Researchers compared its (60) to that of the widely used combination of Sustiva and Combivir. Combivir (61) two drugs, AZT and 3TC. The researchers say that after one year of treatment, the new pill suppressed HIV levels in more patients and with (62) side effects. Gilead paid for the study. Professor Joel Gallant at the Johns Hopkins School of Medicine in Baltimore, Maryland, led the research. He is a paid adviser to Gilead and Bristol-Meyers Squibb as well as the maker of Combivir, GlaxoSmithKline. Glaxo Smith Kline reacted (63) the findings by saying that a single study is of limited value. It says the effectiveness of Combivir has been shown in each of more than fifty studies. The price of the new once-daily pill has not been announced. But Gilead and Bristol-Myers Squibb say they will provide it at reduced cost to developing countries. They plan in the next few months to ask the United States Food and Drug Administration to (64) the new pill. There are limits to who could take it because of the different drugs it contains. For example, (65) women are told not to take Sustiva because of the risk of birth disorders. Experts say more than forty million people around the world are living with HIV.

单选题They agreed to modify their policy.

单选题Volunteers are being recruited(征募) to eat raw potatoes in the first human trials of a vaccine grown in genetically engineered vegetables. Researchers in Texas hope that people who eat the potatoes will be protected against common gut(肠，肠子) infections. They believe this technique could prove to be a cost-effective way of growing vaccines in developing countries where such diseases are still killers. Other researchers previously succeeded in using similar techniques to produce potential vaccines Now Hugh Mason and his colleagues at Texas A & M University(得克萨斯农业及机械大学) their plant vaccines on mice and plan to recruit 15 volunteers for a human trial. The team first tested the technique in tobacco plants. They took a strain of Escherichia coli(大肠杆菌) bacteria that causes food poisoning, and identified the part of the poison which binds to its victims gut cells. They then used a modified plant bacterium called Agrobacterium tumefasciens to transfer the segment of DNA which manufactures the binding protein into the tobacco plant. Under normal circumstances, these bacteria transfer packets of DNA into plant cells to force the plant to manufacture the nutrients they need. But in the modified bacteria, the DNA package includes the gene to pro- duce the binding protein. Once the foreign DNA segment was incorporated(结合，合并) into the tobacco's own DNA, the bacteria were killed off with antibiotics. Mason's team then grew these modified tobacco plants and found that they produced the E. coli binding protein. Proof of success came when the tobacco leaves were mashed up(捣碎) and squirted into the stomachs of mice. Mason says that within days the mice started producing specific antibodies to the E. coli poison, but suffered no ill effects from digesting the binding protein. Mason then produced genetically engineered potatoes and fed these to mice, with similar results. Mason's team have used plants to produce vaccines against a number of other infectious agents. For example, they have made a vaccine using a protein from the shell of the Norwalk virus, which causes diarrhoea(腹泻) in children. A third vaccine has also been produced in tobacco using a surface protein from the hepatitis B virus. But Mason says that so far they have only been able to produce small amounts of it in potatoes. Although a vaccine already exists against hepatitis B, a cheaper plant version could make mass immunisation(群众性免疫) possible. One problem with growing potatoes to produce vaccines is that cooking tends to destroy the protein component of the vaccine, so they must be eaten raw. Mason thinks that bananas may be a better option. "One banana could potentially produce a whole host of different vaccines," says Mason.

单选题 阅读下面的短文，文中有15处空白，每处空白给出了4个选项，请根据短文的内容从 4个选项中选择1个最佳答案。 {{B}}A Special Clock{{/B}} Every living thing has what scientists call a biological clock that controls behavior. The biologicai clock______(51) plants when to form flowers and when the flowers should open. It tells insects when to______(52) the protective cocoon (防护卵袋) and fly away, and it tells animals and human beings when to eat, sleep and wake. Events outside the plant and animal______(53) the actions of some biological clocks. Scientists recently found, for example, that a tiny animal changes the color of its fur because of the______(54) of hours of daylight. In the short______(55) of winter, its fur becomes white. The fur becomes gray brown in______(56) in the longer hours of daylight in summer. Inner signals control other______(57) clocks. German scientists found that some kind of internal clock seems' to order birds to begin their long migration ______(58) twice each year. Birds______(59) from flying become restless when it is time for the trip,______(60) they become calm again when the time of the flight has ended. Scientists say they are beginning to learn which______(61) of the brain contain biological clocks. An American researcher, Martin Moorhead, said a small group of cells near the front of the brain______(62) to control the timing of some of our actions. These______(63) tell a person when to wake, when to______(64) and when to seek food. Scientists say there probably are other biological clock Cells that ______(65) other body activities.

单选题She is a lovely and gracious woman.

单选题At the age of 30, Hersey suddenly became a celebrity .

单选题Use of Trademarks A company must determine whether or not to apply for trademark protection under the federal Lanham Act of 1946 or state law. A trademark gives a firm exclusive use of a "word, symbol, combination of letters or numbers, or other devices such as distinctive packaging used to identify the goods of one company and to distinguish them from other companies" for as long as they are marketed. Trademarks are voluntary and require a registration procedure that can be time consuming, complex, and expensive. A multinational firm must register trademarks in every country in which it operates. In order for a trademark to be legally protected, it must have a distinctive meaning that does not describe an entire product category, not be confusingly similar to other trademarks, be used in interstate commerce, and not imply characteristics that the product does not possess. A surname by itself cannot be registered, because anyone can do business under his or her name. However, an surname can be registered if used to describe a specific business (e. g. ,Roy Roger's Restaurants). When brands become too popular or descriptive of a product category, they run the risk of becoming public property. Then a firm loses its trademark position. Brands that are fighting to remain exclusive trademarks include Xerox, Levi's Frigidaire, Formica, Kleenex, and Teflon. Brands of former trademarks that are now considered generic and therefore public property are cellophane(赛璐玢),aspirin, kerosene(煤油),cola, linoleum(漆布),and monopoly. DuPont used careful research to retain a trademark for Teflon. As company survey showed that 68 percent of the consumers questioned identified Teflon as a brand name. This enabled DuPont to win a court case against a Japanese firm using the name Teflon. On the other hand, the U. S. Supreme Court ruled that "Monopoly'was a generic term that could be used by any game maker. Likewise, a federal court ruled that Miller could not trademark the single word Lite for its lower-calorie(低热量) beer. Trademark protection is essential to many firms because exclusive use of brands and symbols enables them to maintain long-established images and market shares.

单选题The newspaper did not mention the degree of the damage caused by the fire.

单选题Because {{U}}administering{{/U}} the whole company, he sometimes has to work around the clock. A.adjusting B.evaluating C.engaging D.managing

单选题The travelers were ready to enjoy the spectacular tidal waves when suddenly a thick fog came up and obscured the whole scene. A. blurred B. belittled C. banned D. collapsed

单选题The researchers have just completed a study of driving situations.

单选题Techniques to (employ) the energy of the sun are being developed.