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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A. I Am A Pencil B. What It Takes To Help Me Out

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C. The Most Scenic Drives in America D. I Am A Pencil

3.From the book I Am A Pencil, we can learn that Sam Swope’s students _______.

A. are homeless children B. have the same beliefs

C. like writing poetry D. are in different grades

4.What can we learn from the passage?

A. I Am A Pencil is written by Jedwin Smith.

B. What It Takes To Help Me Out is about troubled teens.

C. You have to pay $47.88 for The Most Scenic Drives in America.

D. Jedwin Smith was killed in Vietnam.

5.What type of writing is this passage?

A. An advertisement. B. A news report.

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Last week my youngest son and I visited my father at his new home in Tucson,Arizona.He moved there a few years ago,and I was eager to see his new place and meet his friends.

My earliest memories of my father are of a tall,handsome,successful man devoted to his work and family but uncomfortable with his children.As a child I loved him,as a school girl and young adult I feared him and felt bitter about him.He seemed unhappy with me unless I got straight A's and unhappy with my boyfriends if their fathers were not as "successful" as he was.Whenever I went out with him on weekends,I used to struggle to think up things to say,feeling on guard.

On the first day of my visit,we went out with one of my father's friends for lunch at an outdoor cafe.We walked along that afternoon,did some shopping,ate at the street table,and laughed over my son's funny facial expressions. Gone was my father's critical(挑剔的)air and strict rules.Who was this person I knew as my father,who seemed so friendly and interesting to be around?What had held him back before?

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