The researchers, led by Hwang Woo-suk, insist they cloned an Afghan hound, only to help investigate (研究) human disease, including the possibility of cloning stem cells (干細(xì)胞) for treatment purposes.
But others immediately renewed calls for a global ban (禁令)on human reproductive cloning before the technology moves any farther.
"Successful cloning of an increasing number of species confirms the general impression that it would be possible to clone any species of mammals, including humans," said Ian Wilmut, a reproductive biologist at the University of Edinburgh who produced the first cloned mammal, Dolly the sheep, from an adult cell nearly a decade ago.
Researchers have since cloned cats, goats, cows, mice, pigs, rabbits, horses, deer, mules and gaur, a large wild ox of Southeast Asia. So far, efforts to clone a monkey or another primate with the same techniques have failed.
Uncertainties about the health and life span (壽命) of cloned animals continue to exist; Dolly died at a young age in 2003 after developing cancer and arthritis.
Wilmut and others complimented Hwang's achievement, reported Wednesday in the journal Nature. But they said politicians and scientists must face the larger issue — how to go on with the research without crossing the moral boundary of copying human life in the lab.
"The ability to use the technology is hopeful," said Robert Schenken, president of the American Society for Reproductive Medicine. "However, the paper also points out that in dogs as in most species, cloning for reproductive purposes is unsafe."
The cloned puppy was the lone success from more than 100 dogs implanted (嵌入)with more than 1,000 cloned embryos.
In a news conference in Seoul, the cloning team also condemned(譴責(zé))the reproductive cloning of humans as "unsafe and inefficient." Human reproductive cloning already is banned in South Korea. Other nations, including the United States, are divided on whether to ban just human cloning or cloning of all kinds, including the production of stem cells.
56. An Afghan hound is a kind of ______.
A. cat           B. goat          c. cow          D. dog
57. A ______ is a large wild ox of Southeast Asia.
A. horse          B. deer          C. mules        D. gaur
58. Accrding to the passage, scientists haven’t been able to clone a ______ so far.
A. deer           B. mule         C. mouse        D. monkey
59. The underlined word complimented is probably similar in meaning to ______.
A. praised         B. doubted       C. refused      D. gave up
60. The cloning of human beings is banned in ______. 
A. South Korea                        B. the United States
C. both South Korea and the United States   D. neither South Korea nor the United States


【小題1】D
【小題2】D
【小題3】D
【小題4】A
【小題5】A

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According to the text,there exists a lot of ________ in sweet potatoes.

[  ]

A.

fiber,beta carotene,other earotenoids,vitamin E and C

B.

beta carotene,other carotenoids,fiber,vitamin A and E

C.

vitamin A,beta carotene,fiber,vitamin E and C

D.

beta carotent,other carotenoids,vitamin A and E

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This text as a whole suggests that eating sweet potatoes can help ________

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A.

cut your risk of stroke and heart disease

B.

protect against breast,lung and stomach cancers

C.

protect against ailments ranging from cataracts to cancer

D.

you stay healthy and reduce your risk of life shortening diseases

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“This vitamin pill in an orange jacket”in the passage refers to ________

[  ]

A.

sweet potato

B.

vitamin C pill

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vitamin E pill

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beta carotene

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A.

The Vitamin Superstar

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On Sweet Potatoes

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Beta Carotene and Vitamins

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閱讀下面短文,從所給四個(gè)選項(xiàng)中,選出最佳答案。

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A They talk in words

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