lead a … life（）
A.our society is becoming much worse than before
B.in our modem society it is hard to lead a quiet life
C.the old days were much happier than the present time
D.it is impossible for us to deal with noise as wedid before
me of medical science. Activists deny that we are trying to help and say it is () of our evil and cruel (). A more reasonable argument, however, can be advanced in our (). Life is often () to animals and human beings. Teenagers are flung from trucks and suffer severe head (). Young children () able to walk find themselves at the bottom of swimming pools while a parent is occupied with something else. From everyday germs to gang (), no life is free of pain. Physicians hoping to relieve the eternal suffering of these tragedies have only three choices: 1) create an animal model of the problem to understand the process and test new therapies; 2) experiment on human beings (some experiments will succeed, most will fail); or 3) leave medical knowledge static, hoping that () discoveries will lead us forward.
Human Heart Can Make New Ceils
Solving a longstanding (为时甚久的) mystery, scientists have found that the human heart continues to generate new cardiac (心脏的) 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 (心肌细胞), 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 cells changes over time, Frisen added. In a 20-year-old, about 1 percent of cardiomyocytes are exchanged each year, but the turnover (更替) 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 be potentially possible to develop pharmaceuticals (药物) 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 (疗法) 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.
The human heart stops producing cardiac cells
A．when a person becomes old.
B．as soon as a person gets sick.
C．immediately after a person is born.
D．once a person dies.
For the past several decades, it seems there's been a general consensus on how to get ahead in America: Get a college education, find a reliable job, and buy your own home. But do Americans still believe in that path, and if they do, is it attainable？ The most recent National Journal poll asked respondents about the American dream, what it takes to achieve their goals, and whether or not they felt a significant amount of control over their ability to be successful. Overwhelmingly, the results show that today， the idea of the American dream—and what it takes to achieve it—looks quite different than it did in the late 20th century. By and large, people felt that their actions and hard work—not outside forces—were the deciding factor in how their lives turned out. But respondents had decidedly mixed feelings about what actions make for a better life in the current economy. In the last seven years, Americans have grown more pessimistic about the power of education to lead to success. Even though they see going to college as a fairly achievable goal, a majority—52 percent—think that young people do not need a four-year college education in order to be successful. Miguel Maeda, 42, who has a master's degree and works in public health, was the first in his family to go to college, which has allowed him to achieve a sense of financial stability his parents and grandparents never did. While some, like Maeda, emphasized the value of the degree rather than the education itself, others still see college as a way to gain new perspectives and life experiences. Sixty-year-old Will Fendley, who had a successful career in the military and never earned a college degree, thinks "personal drive" is far more important than just going to college. To Fendley， a sense of drive and purpose, as well as an effective high-school education, and basic life skills, like balancing a checkbook, are the necessary ingredients for a successful life in America. 51.It used to be commonly acknowledged that to succeed in America, one had to have _____.
A.an advanced academic degree
B.an ambition to get ahead
C.a firm belief in their dream
D.a sense of drive and purpose
52.What is the finding of the latest National Journal poll concerning the American dream_____
A.More and more Americans are finding it hard to realize.
B.It remains alive among the majority of American people.
C.Americans' idea of it has changed over the past few decades.
D.An increasing number of young Americans are abandoning it.
53.What do Americans now think of the role of college education in achieving success_____
A.It still remains open to debate.
B.It has proved to be beyond doubt.
C.It is no longer as important as it used to be.
D.It is much better understood now than ever.
54.How do some people view college education these days_____
A.It promotes gender equality.
B.It needs to be strengthened.
C.It adds to cultural diversity.
D.It helps broaden their minds.
55.What is one factor essential to success in America, according to Will Fendley_____
A.A desire to learn and to adapt.
B.A strong sense of responsibility.
C.A willingness to commit oneself.
D.A clear aim and high motivation.
"Our students are a pretty active bunch, but we found that they didn't【C6】______appreciate the value of what they did【C7】______the lecture hall," says Jeff Goodman, director of careers and employability at the university. "Employers are much more【C8】______than they used to be. They used to look for【C9】______and saw it as part of their job to extract the value of an applicant's skills. Now they want students to be able to explain why those skills are【C10】______to the job.
Students who sign【C11】______for the award will be expected to complete 50 hours of work experience or【C12】______work, attend four workshops on employ ability skills, take part in an intensive skills-related activity【C13】______crucially, write a summary of the skills they have gained. 【C14】______efforts will gain an Outstanding Achievement Award. Those who【C15】______best on the sports field can take the Sporting PLuS Award which fosters employer-friendly sports accomplishments.
The experience does not have to be【C16】______organised. "We're not just interested in easily identifiable skills," says Goodman. "【C17】______, one student took the lead ir dealing with a difficult landlord and so【C18】______negotiation skills. We try to make the experience relevant to individual lives.
Goodman hopes the【C19】______will enable active students to fill in any gaps in their experience and encourage their less-active【C20】______to take up activities outside their academic area of work.