Medical drugs sometimes cause more damage than they cure. One solution to this problem is to put the drugs inside a capsule, protecting them from the body—and the body from them—until they can be released at just the right spot. There are lots of ways to trigger (引发) this release, including changing temperature, acidity, and so on. But triggers can come with their own risks—burns, for example. Now, researchers in California have designed what could be a harmless trigger to date: shining near-infrared light (NIR, 近红外线) on the drug in the capsule.
The idea of using light to liberate the drug in the capsule isn’t new. Researchers around the globe have developed polymers (聚合物) and other materials that begin to break down when they absorb either ultraviolet (UV, 紫外线) or visible light. But tissues also readily absorb UV and visible light, which means the drug release can be triggered only near the skin, where the light can reach the capsule. NIR light largely passes through tissues, so researchers have tried to use it as a trigger. But few compounds (化合物) absorb NIR well and go through chemical changes.
That changed last year when Adah Almutairi, a chemist at the University of California, San Diego, reported that she and her colleagues had designed a polymer that breaks down when it absorbs NIR light. Their polymer used a commercially available NIR-absorbing group called o-nitrobenzyl (ONB). When they catch the light, ONB groups fall off the polymer, leading to its breakdown. But ONB is only a so-so NIR absorber, and it could be poisonous to cells when it separates from the polymer.
So Almutairi and her colleagues reported creating a new material for capsules that’s even better.This one consists of a long chain of compounds called cresol groups linked in a polymer. Cresol contains reactive(易反应的) components that make it highly unstable in its polymeric form, a feature Almutairi and her colleagues use to their advantage. After polymerizing the cresols, they cap each reactive component with a light-absorbing compound called Bhc. When the Bhcs absorb NIR light, the reactive groups are exposed and break the long polymer into two short chains. Shining additional light continues this breakdown, potentially releasing any drugs in the capsule. What’s more, Almutairi says, Bhc is 10 times better at absorbing NIR than is ONB and is not poisonous to cells.
【小题1】According to the passage, which of the following could be the best trigger?
| A．Temperature change. | B．NIR light. | C．Acidity change. | D．UV light. |
| A．It breaks down when it absorbs NIR light. |
| B．It falls off the polymer and triggers drug release. |
| C．It has not come onto the market up till now. |
| D．It is not effective enough and could be poisonous. |
| A．protected | B．formed | C．exposed | D．combined |
科目：高中英语 来源：安徽省马鞍山市2010届高三下学期第三次教学质量检测试题（英语） 题型：阅读理解
Drinking a lot of water does not do any good to the body, according to two experts in the United States. In fact, they warn, drinking too much water could be, in certain Cases, harmful.
In a study, Dr Stanly Goldfarb and Dr Dan Negoianu, both of the Renal, Electrolyte and Hypertension Division at the University of Pennsylvania, the United States, have denied the popular belief that drinking a lot of water clears body toxins (毒素) better, improves skin, and helps reduce weight.
Dr Goldfarb and Dr Negoianu say that they found little proof to support the public opinion that drinking 8 glasses of water every day benefits health. At the same time, they found little proof of harm in drinking 8 glasses of water every day.
It is widely believed that in some cases — such as athletes, people who live in hot, dry environments, and those with certain medical conditions — drinking a lot of water indeed helps, but no studies have been done to prove the benefits of this practice in average, healthy people, the website medheadlines. com reports.
The study at the University of Pennsylvania also examined reports that some people experienced increased headaches when their consumption of water was low. In one small study, which the doctors reviewed, the group drinking the most water reported fewer headaches than the control group, “but the difference in the number of headaches was so small between the two groups as to be considered unimportant.”
The researchers concluded that there is no scientific proof to support that average, healthy people need to drink at least 8 glasses of water each day.
The website medheadlines. com says that, according to an Indian doctor, drinking too much water is harmful. If water enters the body more quickly than it can be removed, problems can occur.
1. What’s the key message delivered in the passage?
A. Drinking too much water might bring harm.
B. Whether to drink enough water makes no difference.
C. Drinking too much water may cause headaches.
D. Average, healthy people should drink more water.
2. We can learn from the passage that 8 glasses of water every day ________.
A. proves good for the body B. has scientific proof of harm
C. is sure to reduce headaches D. is generally considered necessary
3. Who may agree that drinking lots of water helps to lose weight?
A. Two experts. B. General public.
C. An Indian doctor. D. A website.
4. According to the passage, we know that ________.
A. the website medheadlines. com is developed by an Indian doctor
B. the study was carried out by two experts with an Indian doctor
C. the two experts performed the study at the University of Pennsylvania
D. drinking 8 glasses of water every day can cure certain diseases
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科目：高中英语 来源：2011-2012学年吉林省长春二中高一下学期期末考试英语试卷（带解析） 题型：阅读理解
Can feeling of nostalgia (怀旧) be good for you? or is it unhealthy to have a strong love for the past?
For years, medical experts have studied nostalgia and the reasons for it. Many experts warn that too much nostalgia is harmful. They say linger (徘徊) in the past shows that a person is unhappy with his present life. These feelings keep the person from living his life to its fullest.
Dr. Louise Kaplan has written several books about nostalgia. She says these feelings often begin when a young person is between 13 and 19 years old.
"This is the time when you must face the loss of your childhood, " Kaplan says. "You see your new life is easily destroyed. But you think romantically about a golden
past. You remember your childhood as a time when life was perfect."
These feelings continue as a person gets older, Kaplan adds. She says many grown persons have a hard time keeping up with changes in the modem world, so they think back to their younger years. At that time the world seemed simple and more harmless.
Kaplan says these feelings are not always actually existing. The good old days weren't always good. However, she says nostalgia can be helpful, if used properly.
"Feelings of nostalgia can cause you to remember a time when you had high hopes and dreams, " Kaplan says. "It might give you the strong wish to catch those dreams today, in your present life." She adds that nostalgia can prevent you from "cutting yourself off from your aim."
"At its best, " Kaplan says, "nostalgia has the ideas for the future."
【小题1】According to the passage, feelings of nostalgia _____.
| A．can cause you to think of your past which was full of hopes and dreams |
| B．can make you succeed in life |
| C．fill one with hopes for the future |
| D．bring about a love for the past and a hope for the future |
| A．they can hardly keep up with changes in today's world |
| B．times are hard, so they can not keep up with changes |
| C．many grown persons have little time keeping up with changes in the modem world |
| D．they lived in the past, of which they are always proud |
| A．Too much nostalgia is harmful. |
| B．Nostalgia shows that a person is not satisfied with his present life. |
| C．Only women have feelings of nostalgia. |
| D．A little nostalgia can make a person's life more colorful. |
| A．nostalgia is sure to be harmful |
| B．nostalgia can be helpful |
| C．nostalgia is always very good |
| D．nostalgia is bad indeed |
| A．Thoughts on Nostalgia |
| B．The reasons for Nostalgia |
| C．Why Do They Think Back to the Past |
| D．Nostalgia, Good or Bad |
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科目：高中英语 来源：20102011学年辽宁省丹东市高二下期末考试英语 题型：阅读理解
To get an extra 14 years of life, don't smoke, eat lots of fruits and vegetables, exercise regularly and drink alcohol in a proper amount．That is according to a study published this Monday in the Public Library of Science Medicine Journal．
After tracking more than 20,000 people aged 45 to 79 years in the United Kingdom from about 1993 to 2007, Kay-Tee Khaw of the University of Cambridge and his colleagues found that people who adopted these four healthy habits lived all average of 14 years longer than those who didn't．
“We've known for a long time that these behaviors are good things to do, but we've not seen this benefit before, ”said Susan Jebb, head of Nutrition and Health at Britain's Medical Research Council．“The benefit was also seen regardless of whether or not people were fat and what social class they came from．”
Study participants（参与者）scored a point each for not smoking, regular physical activity, eating five servings of fruits and vegetables a day and moderate alcohol intake．
Public health experts said they hoped the study would inspire governments to introduce policies helping people to adopt these changes．But because the study only observed people rather than testing specific changes, it would be impossible to conclude that people who suddenly adopted these healthy behaviors would surely gain 14 years．
“We can't say that any person could gain 14 years by doing these things, ”said Dr．Tim Armstrong, a physical activity expert at the World Health Organization．“The 14 years is an average across the population of what's theoretically（理论上地）possible．”
“Most people know that things like a good diet matter and that smoking isn't good for them, ”Susan Jebb said．“We need to work on providing people with much more practical support to help them change．”
1.Which of the following DOESN'T belong to the four healthy habits?
A．Eat five servings of fruits and vegetables a day．
B．Do proper exercise in the morning every day．
C．Drinking alcohol in the proper amount every day．
D．Having a cigarette before going to bed every day．
2.We can learn from the passage that ．
A．Susan Jebb did not take part in the study．
B．the study observed people as well as tested specific changes．
C．there's no need for people under 45 to adopt these good habits．
D．only those from first class can benefit from these healthy behaviors．
3.What can be inferred from the passage?
A．All the people are well aware of the harm of their bad habits．
B．People aged 45 to 70 have bad habits in the United Kingdom．
C．Governments should take measures to help people change their bad habits．
D．People have adopted the four healthy habits after knowing they're good．
4.What would be the best title for this passage?
A．Smoking and Drinking Cuts You 14 Years
B．How to Live a Much Healthier Life
C．Healthy Habits May Give Extra 14 Years
D．How to Make Your Life Longer Than Others
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科目：高中英语 来源：20102011学年北京东城区高三下学期第二次联考英语卷 题型：其他题
根据短文内容，从短文后的七个选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。
Are you a team person? Are you at your best as part of a small, tightly united group of dedicated workers? If so, the future may hold more for you than you think.
1. That’s happening in those areas of business and data processing where one person and a computer can replace a team of workers.
2. High technology has led to a new type of teamwork in a number of fields, including advertising, scientific research, engineering design, architecture and ocean exploration.
Through computer networking, scientists, engineers, and technicians at different locations — often thousands of miles apart --- can work on the same project at once. 3.
Examples? An engineering team can now design and try out a robot system --- a new manufacturing process, or an entire factory — before it is built. An architectural team can do the same with a building or a bridge. A medical team can simulate a dangerous operation before performing it on a patient.
Of course, computer-assisted team effort doesn’t end with investigation and simulation. 4. “CAD-CAM --- computer-aided design and manufacture --- is breaking down barriers between traditional design and manufacturing functions.” explains Dr. Prakash Rao, an engineering manager at General Electric. “Interdisciplinary(跨学科的) teams and engineers follow a product from concept to production. Everything is interconnected like a network.”
5. A team that produces robots may use them to explore space and ocean depths. For high-technology teamwork, the future seems limitless.
A. They can exchange ideas, try out different designs, and test their results.
B. It now usually continues into actual design, manufacturing, and testing.
C. In the future, team work will be highlighted by the introduction of new technology.
D. Sometimes, a computer-aided effort can extend beyond production.
E. But, elsewhere, teamwork is very much alive.
F. It ends in the products which are extensions of the traditional design.
G. High technology, some predicted, would make team work a thing of the past.
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科目：高中英语 来源：2009年佛山一中高二下学期期末考试英语卷 题型：完型填空
阅读下面短文，掌握其大意，然后从16-25各题所给的A、B、C和D项中，选出最佳选项，并在答题卡上将该项涂黑。
Most children want to be pop stars or footballers when they grow up. But 11-year-old Amy Jones had the chance to ____16____ more about her ____17____ job—a medical biologist —when she won an essay writing competition for primary students.
Amy’s __18__ for the best essay on “What I want to be when I’m older” was a day at Oxford Medical Science Institute. Staff organised a special programme for the would-be __19__, introducing her to the projects being worked on by medical biologists at Oxford. The sessions included a look at the ___20___ of medical biologists in fighting cancer and ___21___ to become a medical biologist.
Amy said she was ___22___ to become a biologist after watching a television programme. In her essay she wrote: “The medical biologist plays a big part in many discoveries and it would be a challenging, exciting and ___23__ job.”
Dr. Kathryn Robson, the Institute director said: “ It’s ___24___that we encourage young people to study science and think about scientific research as a job. I hope Amy now has a better __25__of what it takes to become a medical biologist.”
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