题目内容

Researchers in China and the United States have developed a new cataract(白内障)treatment with cells that has restored vision in babies in a trial and may eventually be used in adults.

The treatment- by doctors and staff members at the University of California, San Diego School of Medicine and Sichuan and Sun Yat-sen universities in China-was published in March 9 edition of the scientific journal Nature.

A cataract is a clouding of the normally clear lens(晶体)of an eye. Typical cataract operation involves the removal of the cloudy lens and the insertion of an artificial one. The new operation has been tested in animals and during a small, human trial. It resulted in fewer complications(并发症)than the current harmful operation, and in regrown lenses with superior visual function in all 12 of the baby cataract patients who received the procedure.

A congenital cataract- lens clouding that occurs at birth or shortly after- is important cause of blindness in children. In the new research, Kand Zhang, head of ophthalmic genetics at US San Diego’s Shiley Eye Institute, and his colleagues relied on the regrown potential of endogenous(同源的)stem cells.

According to Zhang, endogenous stem cells are different from other stem cells that are typically grown in a laboratory, transplanted into a patient, and can have risks of immune(免疫的)rejection, infection or cancers. Zhang told CBS News, “We invented a new operation to make a very small opening at the side of a cataractous lens bag, remove the cataract inside, allow the opening to heal, and promote potential lens stem cells to regrow an entirely new lens with vision.”

The human trial involved 12 babies under the age of 2 who were treated with the new method, while 25 babies received thee standard operation care.. The latter group experienced a higher incidence of pos- operation danger, early- onset eye high blood pressure and increased lens clouding. The scientists reported fewer complications and faster healing among the 12 babies who has the new procedure.

1.What is the text mainly about?

A. The concept of the cataract

B. A new cataract treatment with stem cells

C. Bad effects of post-operation in the cataract

D. The reasons why the cataract comes into being

2.Which of the following best describe the new cataract treatment according to the passage?

A. Convenient B. Comfortable

C. Cheap D. Safe

3.What can we learn about the new cataract treatment?

A. It has more risks

B. It may be used widely

C. It has been put into practice widely

D. It can only restore vision in babies

4.What does the underlined word “congenital” in the fourth paragraph mean?

A. Born B. Strange

C. Serious D. Dangerous.

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Yuoki, a restaurant in Germany, is not your everyday all-you-can-eat buffet (自助餐). For starters, there isn't an actual buffet to fill your plate. Instead, customers are seated at a table and provided with iPads which they can use to order up to five small dishes every ten minutes. They can eat as much as they want for 120 minutes, but having the food served at short intervals (间隔) allows diners to constantly assess how hungry they are and order accordingly, preventing food waste. Also, the owner, Luan Guoyu, believes, “our eyes are bigger than our stomach”, so not being able to see the cooked food at the buffet prevents people from ordering more food than they can actually eat.

But Luan Guoyu's most effective way of fighting food waste, and the one that has attracted media attention, is his ?1 ($1.15) fine for food still left on the plate. “It’s called ‘ all-you-can-eat’ ” he says, adding that the extra charge is not meant to increase his income, but to act as a warning against wasting food.

Luan Guoyu's system is unique in the state of Baden-Wurttemberg, but not in Germany. Okinii, a Japanese-style restaurant in Dusseldorf, has also been charging customer, the same ? 1 tax for unfinished food on their plates since 2013.

With so many people living on the edge of their nations, and food waste becoming a serious problem in developed countries, it will be interesting to see if more restaurants will start carrying out the “eat up or pay up” policy. Even if they give the money from this fine to charity, it would still help them to save money in dealing with waste, so it's a win for everyone.

1.What does the underlined word “assess” in Paragraph 1 probably mean?

A. Doubt. B. Realize.

C. Judge. D. Compare.

2.What will Luan Guoyu do when people can’t finish the food on their plates?

A. He will charge them extra money.

B. He will advise them to eat up the food.

C. He will ask them to take the food away.

D. He will warn them to order less food next time.

3.What is the text mainly about?

A. Various German restaurants.

B. The seriousness of food waste.

C. Secrets of managing a restaurant.

D. Special ways to fight food waste.

4.What does the author think of the “eat up or pay up” policy?

A. Unfair. B. Funny.

C. Reasonable. D. Doubtful.

Teens For Planet Earth

This is a social networking site for teenagers who want to get involved in protecting our planet. They can connect with other green-minded teens, choose a project or create their own. Teens For Planet Earth encourages young folks to get busy in their own communities. They offer guidance on local projects with categories such as habitats, animals, water and education. Awards are given to active members.

Meez

At Meez, teens can create their own avatars(头像), rooms and virtual pets. It is a social community of creative people that combines avatars, virtual worlds and games. Meez offers contests and chat as well as homework help, a fashion central and a writers’ corner. A chat area for younger teens is available. Other areas are music, geek(极客)central, art and sports.

Cyberteens

Cyberteens is another cool site that celebrates the teen years. Here teenagers can find community, games, and news. There is a link called “creativity” where teens can share their poems, stories, photos and artwork. The “cool links” section offers a huge variety of options to the curious teens. This site also has surveys and helps with jobs and school work.

Student.com

Student.com is a resource site for teens and high school students. Its social network has over 900,000 members. Members earn points to win prizes just by browsing and they offer several multi-player games. Points are used to buy items at auction(拍卖会). Student.com is filled with useful information and articles.

1.What is Teens For Planet Earth aimed to?

A. Set up a project.

B. Give awards to teens.

C. Get young folks busy.

D. Give advice on local projects.

2.Which website offers assistance in jobs?

A. Teens For Planet Earth. B. Meez. C. Cyberteens. D. Student.com.

3.What makes Student.com special among these websites?

A. It has the most members.

B. Teens can read articles on it.

C. It offers help on school work.

D. Teens can make purchases on it.

4.What can we infer about the websites mentioned in the text?

A. They provide game platforms.

B. They benefit teens in their social life.

C. They award outstanding teens.

D. They offer various study guidance.

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