单选题We have to put up with her behavior.

单选题Emily Greene Balch's steadfast labor for freedom and for cooperation among individuals and peoples brought her the Nobel Peace Prize in 1946.A. unwaveringB. acceleratedC. uninhibitedD. aggressive

单选题Relief workers were shocked by what they saw.

单选题{{B}}第二篇{{/B}} Panic A panic is a form of collective in which a group of people, face with an immediate threat, react in an uncoordinated and irrational way. Their behavior is uncoordinated in the sense that cooperative social relationships and beak down. It is irrational in the sense that people's actions are not appropriate for the goals they wish to achieve. The progress of a panic follows a fairly typical course. A sudden crisis occurs; people experience intense fear; normal social expectations are broken; each individual tries desperately to escape from the source of danger; mutual cooperation breaks down; and the situation becomes even more threatening as a result. Panics are especially likely to occur in unusual conditions in which everyday norms have little relevance, such as fires, floods, earthquakes or military invasions. Some kind of response is necessary in these situations, but there are few social norms that specify an appropriate reaction. Thus, when a passenger aircraft makes a crash landing people may attempt to flee before fire breaks out and cause an explosion, but there only succeed in stopping themselves and others by creating bottlenecks at the exits. Awareness of bottlenecks may lead to increased panic, with people fighting and trampling one another in the effort to escape. Despite intensive training of airline personnel in emergency evacuation procedures, a high proportion of passenger deaths are caused by a panic that prevents people from escaping in time. The most dramatic panics are those that occur in situations of extreme emergency, but not all panics are quite so frantic or short-lived. A different form of this collective behavior is the financial panic, which is typically provoked by rumor that the price of stocks will fall or that a bank will be unable to repay its depositors. The classic example, of course, occurred at the outset of the Great Depression in 1929 : as in other forms of panic, the individuals involved tried to protect their own interests, and in so doing they worsened the situation for themselves and everyone else. By trying to sell their stocks as quickly as possible, people ensured that the price of stocks did fall; by demanding their money back from banks, they ensured that the banks actually did collapse.

单选题I {{U}}am sure to tell{{/U}} you that there's no danger.

单选题Soon, creating a hospital in cyberspace may no longer be science fiction. NASA's Ames Research Center and Salinas Valley Memorial HosPital are working toeether in bring a virtual medical facility to the World Wide Web in the enear future. The venture will involve machines that transmit and receive data and three- dimensional images of the human body via a special workstation located at the hospital. Medical professionals will send diagnostic information to NASA. through its Research and Education Network, which will transmit the 3 -D images and data back to the hospital for evaluation and image manipulation. The doctors will then give feedback about how well the network works and the quality of the images. In a virtual hospital, medical professionals will workA. at the real hospital.B. at NASA's Research and Education Network.C. the World Wide Web.D. at a special workstation at hom

单选题He is Upositive/U that the dictionary is just what I want.

单选题He was kept in appalling conditions in prison.

单选题 下面有3篇短文，每篇短文后有5道题。请根据短文内容，为每题确定1个最佳选项。{{B}}第一篇{{/B}} {{B}} High Stress May Damage Memory{{/B}} According to a report issued in May 1998, elderly people who have consistently high blood levels of cortisol don’t score as well on memory tests as their peers with lower levels of the stress hormone. What’s more, high levels of cortisol are also associated with shrinking of the hippocampus, a region of the brain that plays a key role in learning and memory. The findings suggest that even cortisol levels in the normal, "healthy" range can actually accelerate brain aging. The study results "now provide substantial evidence that long-term exposure to adrenal stress hormones may promote hippocampal aging in normal elderly humans," write Nada Porter and Philip Land- field of the University of Kentucky in Lexington in their editorial. Cortisol is a hormone released in response to stress by the adrenal glands ,which sit on top of the kidneys. Over a 5 to 6-year period ,Dr. Sonia Lupien and his colleagues measured 24-hour cortisol levels in 51 healthy volunteers ,most of whom were in their 70s. Despite wide variation in cortisol levels, the participants could be divided into three subgroups, those whose cortisol progressively increased over time and was currently high (increasing/high); those whose cortisol progressively increased over time and was currently moderate (increasing/moderate); and subjects whose cortisol decreased, but was currently moderate (decreasing/moderate). The researchers tested the volunteers' memory on six people in the increasing/high category and five people in the decreasing/moderate group. The groups did not differ on tests of immediate memory, but the increasing/high cortisol group had other memory problems compared with those in the decreasing/moderate group. The researchers also found that the total, volume of the hippocampus in those in the increasing/high group was 14 % lower than those in the decreasing/moderate group, although there were no differences in other brain regions. The results suggest that "... brain aging can be accelerated by levels of adrenal hormones that are not generally regarded as pathological and that variation within, this normal range is related to variation in the rate of brain aging,' write Porter and Landfield. "This further, suggests that chronic stress may accelerate the worsening of hippocampus. '

单选题Housewives who do not go out to work often feel they are not working to their full ability.

单选题Her life is becoming more diverse .

单选题Most people would agree that, although our age far {{U}}surpasses{{/U}} all previous ages in knowledge, there has been no correlative increase in wisdom. A. improves B. precedes C. imposes D. exceeds

单选题Human Heart Can Make New Cells Solving a longstanding mystery, scientists have found that the human heart continues to generate new cardiac cells throughout the life span, although the rate of new cell production slows with age. The finding, published in the April 3 issue of Science, could open a new path for the treatment of heart diseases such as heart failure and heart attack, experts say. "We find that the beating cells in the heart, cardiomyocytes, are renewed," said lead researcher Dr. Jonas Frisen, a professor of stem cell research at the Karolinska Institute in Stockholm, Sweden. "It has previously not been known whether we were limited to the cardiomyocytes we are born with or if they could be renewed," he said. The process of renewing these ceils changes over time, Frisen added. In a 20-year-old, about 1 percent of cardiomyocytes are exchanged each year, but the turnover rate decreases with age to only 0.45 percent by age 75. "If we can understand how the generation of new cardiomyocytes is regulated, it may potentially possible to develop pharmaceuticals that promote this process to stimulate regeneration after, for example, a heart attack," Frisen said. That could lead to treatment that helps restore damaged hearts. "A lot of people suffer from chronic heart failure," noted co-author Dr. Ratan Bhardwaj, also from the Karolinska Institute. "Chronic heart failure arises from heart cells dying," he said. With this finding, scientists are "opening the door to potential therapies to having ourselves heal ourselves," Bhardwaj said. "Maybe one could devise a pharmaceutical agent that would make heart cells make new and more cells to overcome the problem they are facing." But barriers remain. According to Bhardwaj, scientists do not yet know how to increase heart cell production to a rate that would replace cells faster than they are dying off, especially in older patients with heart failure. In addition, the number of new cells the heart produces was estimated using healthy hearts--whether the rate of cell turnover in diseased hearts is the same remains unknown.

单选题Multivitamins Urged for All Pregnant Women A recent study in Tanzania found that when pregnant women took vitamins every day, fewer babies were born too small. Babies that weigh less than two and one-half kilograms at birth have a greater risk of dying. Those that survive are more likely to experience problems with their development. And experts say that as adults they have a higher risk of diseases including heart disease. The World Health Organization estimates that every year twenty million babies are born with low birth weight. Nine out of ten of them are born in developing countries. The new study took place in Dubai. 4,200 pregnant women received multivitamins. The pills contained all of the vitamins in the B group along with vitamins C and E. They also contained several times more iron than the levels advised for women in developed nations. Pregnant women especially in poor countries may find it difficult to get enough vitamins and minerals from the foods in their diet. The scientists compared the findings with results from a group of 4,000 women who did not receive the vitamins. A report by the scientists, from the United States and Tanzania, appeared in the New England Journal of Medicine . Wafaie Fawzi of the Harvard University School of Public Health led the study. None of the women in the study had HIV, the virus that causes AIDS. The scientists reported earlier that daily multivitamins were a low-cost way to reduce fetal deaths in pregnant women infected with HIV. The earlier work in Tanzania also found improvement in the mothers in their number of blood cells known as lymphocytes (淋巴细胞). Lymphocytes increase the body"s immunity against infection. The new study in pregnant women who were not infected with the AIDS virus found that multivitamins reduced the risk of low birth weight. Just under eight percent of the babies born to women who took the multivitamins weighed less than 2,500 grams. The rate was almost nine and one-half percent in the group of women who received a placebo, an inactive pill, instead of the vitamins. But the vitamins did not do much to reduce the rates of babies being born too early or dying while still a fetus. Still, the researchers say multivitamins should be considered for all pregnant women in developing countries.

单选题You don't need to carry large amounts of cash; actually all financial business will be conducted by computers. A. transmissions B. transitions C. transactions D. transportation

单选题William Wrigley first started to experiment with chewing gum.

单选题They had a far better {{U}}yield{{/U}} than any other farm miles away around this year. A. goods B. soil C. climate D. harvest

单选题This sort of thing is bound to happen.

单选题 Effects of Exercise on Elderly Diabetics (糖尿病人) Most older people with. so-called type 2 diabetes (糖尿病) could stop taking insulin (胰岛素) if they would do brisk (轻快的) exercise for 30 minutes just three times a week, according to new medical research results reported in a Copenhagen newspaper. 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 make use of insulin by 30 per cent. This is equal to the effect most elderly diabetics get from their insulin medication (药物治疗) today. Researchers had a group of non-diabetic men and a group of men with type 2 diabetes, 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 make use of as a measure for how well their insulin worked. Associate Professor Dr Flemming Dela of the Muscle Research Center said the tests demonstrated that the exercising diabetics had made as good use of insulin as the healthy non-diabetic 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," Dela said. Insulin is a hormone produced by the pancreas (胰腺), controlling sugar in the body and is used against diabetes. Dela said that to achieve the desired effect diabetics need only exercise to the point where they begin to 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The book provides a concise analysis of the country"s history.