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膳食中蛋白质不足导致六六六、对硫磷毒性增强

A. 实验动物的物种与毒效应
B.实验动物的品系与毒效应
C.实验动物的性别与毒效应
D.实验动物的年龄与毒效应
E.实验动物的生理营养状况与毒效应

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Section Ⅱ Reading ComprehensionPart ADirections:Read the following four texts. Answer the questions below each text by choosing A, B, C or D. Mark your answers on ANSWER SHEET 1. Text 1 For years Internet merchants have poured millions of dollars into new technologies to make their sites easier to use. So why aren’t online customers happier Customer satisfaction levels have remained almost flat through the last several years. The problem, according to Larry Freed, chief executive of a consulting and research firm called ForeSee Results, is not so much that consumers have ignored the many improvements made in recent years. Rather, he said, they still expect more from Internet shopping than it has delivered. "If we walk into a local store, we don’t expect that experience to be better than it was a couple years ago," Mr. Freed said. "But we expect sites to be better. The bar goes up every year." In ForeSee’s latest survey, released last month, just five e-commerce sites registered scores higher than 80 out of 100, and no site scored higher than 85. It was much the same story a year ago, when just five scored higher than 80, with no site surpassing 85. "Scores have inched up over time for the best e-commerce companies, but the overall numbers haven’t moved drastically," Mr. Freed said. "At the same time though, if you don’t do anything you see your scores drop steadily." That dynamic has been a challenge for online merchants and investors, who a decade ago envisioned Internet stores as relatively inexpensive (and therefore extremely profitable ) operations. Now some observers predict a future where online retailers will essentially adopt something like the QVC model, with sales staff pitching the site’s merchandise with polished video presentations, produced in a high-tech television studio. QVC. com is evolving in that direction. The Web site, which sold more than $1 billion in merchandise’ in 2006, has for the last five years let visitors watch a live feed of the network’s broadcast. But in recent months, QVC. com has also given visitors the chance to watch archives of entire shows, and in the coming months visitors will be able to find more video segments from recent shows, featuring individual products that remain in stock. Bob Myers, senior vice president of QVC. com, said the Web site’s video salesmanship is especially effective when combined with detailed product information, customer reviews and multiple photographs. About eight months ago, for instance, a customer said that she could not determine the size of a handbag from the photographs on the site because she could not tell the height of the model who was holding it. Within two weeks the site tested and introduced a new system, showing the bags with women of three different heights. The results were immediate: women who saw the new photographs bought the bags at least 10 percent more frequently than those who had not. Still, Mr. Myers said, video is a critically important element to sales. "E-commerce started with television commerce," he said. "The sites who engage and entertain customers will be winning here in the near future." Such a prospect is not necessarily daunting to other e-commerce executives. Gordon Magee, head of Internet marketing for Drs. Foster & Smith, based in a Rhinelander, Wis. said a transition to video "will be seamless for us." The company, Mr. Magee said, has in recent weeks discussed putting some of its product on video "so customers could see a 360-degree view they don’t have to manipulate themselves. The example of a customer buying a handbag is used to show that

A. visual confirmation and product specifications help improve online sales.
B. online shopping has its own advantages as well as disadvantages.
C. women are more attracted to photographs of products than men buyers.
D. photographs often help to increase immediate sales by at least 10 percent.

An airplane flies because its wings push down on the air flowing past them, and in reaction, the air pushes up on the wings. When an airplane is level or rising, the front edges of its wings ride higher than the rear edges. The angle the wings make with the horizontal is called the angle of attack. As the wings move through the air, this angle causes them to push air flowing under them downward. A sleeper angle of attack will cause the wings to push more air downward. The third law of motion voiced by English physicist Isaac Newton states that every action produces an equal and opposite reaction. In this case, the wings pushing air downward is the action, and the air pushing the wings upward is the reaction. This causes lift, the upward force on the plane, Lift is often explained using Bernoulli’s principle, which states that, in some circumstances, a faster moving fluid(流体) (such as air)will have a lower pressure than a slower moving fluid. The air on the top of an airplane wing is at a lower pressure than the air underneath the wing, but this is an effect of lift, not its cause.Lift is one of the four primary forces acting upon an airplane. The others are weight, thrust, and drag. Weight is the force that offsets lilt. because it acts in the opposite direction. The weight of the airplane must be overcome by the lift produced by the wings, if an airplane weighs 4.5 metric tons, then the lift produced by its wings must be greater than 4.5 metric tons in order for the airplane to leave the ground. Designing a wing that is powerful enough to lift an airplane off the ground, and yet efficient enough to fly at high speeds over extremely long distances, is one of the marvels of aircraft technology. What is the role of the angle of attack

男性,40岁,发热3天,腹痛,腹泻,每日2~3次稀便,无脓血,因头晕、乏力而入院。查:体温不升,血压测不到,双眼结膜充血,水肿,面、颈及上胸部潮红,两腹下及腹壁有多处小出血点。血WBC 32×109/L,异型淋巴细胞12%,Hb160g/L,尿蛋白(+++),大便镜检有白细胞5~8个/HP 进一步确诊应查

A. 大便细菌培养
B. 肾功能
C. 血培养
D. 凝集试验
E. 流行性出血热病毒IgM抗体

A sick or injured person can obtain medical care in several different places. These include provider practices such as medical offices and clinics, hospitals and nursing homes.There are about 200,000 medical offices, clinics, and other provider practices in the United States. Earlier in the 20th century most physicians were single people working in their own offices or in partnership with another doctor. Patients visited the office, received an examination or other service, and paid a fee. This traditional fee-for-service medicine has been declining. Many physicians now practice in groups where they share the same offices and equipment with other doctors. Group practices may combine primary care physicians, several kinds of specialists, laboratories, and equipment for diagnosing disease. Physicians who practice in a group reduce their own expenses and provide patients with a wider range of services.Many doctors are joining with hospitals, insurance companies, and industrial employers to provide managed care for groups of patients. These plans manage to avoid unnecessary services and reduce costs. Rather than taking a fee from each patient, managed care physicians may receive an annual salary from a fixed sum for each patient.Patients who are too sick for care in a doctor’s office go to a hospital. Hospitals offer Patients 24-hour care from a staff of health professionals. They provide services not available elsewhere, such as major surgery, child birth, and intensive care for the critically ill. Hospital care is the most expensive form of health care. Efforts to control health care costs have emphasized reducing the number of patients admitted to hospitals and their length of stay. During the 1980s and 1990s, these efforts led to the closing of more than 600 hospitals.Patients who need long-term medical care because of advanced age or chronic illness may stay in a nursing home. The United States has about 23,000 nursing homes with about 1.3 million patients. According to the article, what is the shortcoming of the hospital()

A. Hospitals offer patients 24-hour care from a staff of health professionals.
B. They provide services not available elsewhere, such as major surgery, child birth, and intensive care for the critically ill.
C. Hospital care is the most expensive form of health care.
D. If you are extremely ill, the best place for you is to go to hospital.

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