题目内容
When a Massachusetts biotech company recently declared that its researchers had cloned human embryos, it conjured up scary images for many people: bad science-fiction movies, Hitler's twisted ambitions, rows and rows of identical humans.
But, like most things in life, the truth is a lot more complicated, more subtle.
The announcement drew a storm of criticism. Ethicists, religious leaders and US President Bush denounced Advanced Cell Technology for going too far. Scientists charged that the experiment was hyped and called it a failure.
The news put a spotlight on the field of cloning, from work with animals to researchers' efforts to use cloning to create tissues for people suffering from debilitating and fatal diseases.
At its most basic level, cloning means creating copies, and in many ways, cloning has been around a long time. When someone cuts a shoot off a green spider plant and re-pots it, that person is creating a clone. Scientists clone or copy genetic material, or DNA, to match suspects to crimes. By copying cells, researchers have been able to create and test drugs. Scientists even use cloning techniques to create copies of the human gene for insulin to help make insulin for people with diabetes.
"Cloning per se is not bad. The ability to clone and make lots of copies of DNA molecules and cells is part of the entire biological revolution and all sorts of good stuff," sags Larry Goldstein, professor of cellular medicine at the University of California, San Diego, School of Medicine.
Cloning a whole animal or a human being, however, is a much more difficult proposition, even without considering the moral implications. The basic method sounds deceptively simple. Scientists allow an egg to mature in a culture dish. They strip out the genetic material from this egg. Then they insert the genetic material of a separate cell, an adult cell. Next, using a chemical mixture or electrical stimulation, researchers trick the egg into thinking it has been fertilised by sperm. This will activate the cell to start dividing.
Essentially, scientists are trying to reprogramme the egg to create a new organism. It's an excruciatingly difficult process. During the past several years, scientists around the world have used this method to clone animals. They've created about a half-dozen different species, including the famous first sheep, Dolly, along with cows, mice, goats and pigs. Experts say these cloned animals could offer a great deal, from herds that produce more milk, to genetically modified animal organs that could be used for transplantation in humans, and even to cattle that lack the gene that makes them susceptible to mad cow disease.
But it has been a tough process. For each species, scientists have had to work out subtle variations on the basic cloning steps, including how to treat the donor cell and what type of stimulation to use to spark the egg to start dividing. Still, fewer than 1% of these cloned embryos produce live offspring.
Even those born alive have abnormalities--some become obese very quickly, some suffer neonatal respiratory failure. Those that die do so suddenly, and scientists can't figure out why.
There is no consensus about what is going wrong in these experiments or why, except that something must be awry in the genetic reprogramming. But almost all scientists agree that aside from the moral debate, cloning hasn't been perfected enough to try in humans.
Professor Larry Goldstein may agree on all of the following statements EXCEPT______.
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It sounded like a wicked idea. Even if the local supermarket was only two blocks away. Just think I could just switch on my PC and do my weekly shopping, then go back to bed and watch Richard and Judy while waiting for the delivery van to turn up. Trouble was, it didn't quite work out like that...
10:53 a.m.
Logged on to the site of A Certain Well Known Food Retailer Who Shall Remain Nameless. Immediately, I am presented with a bewildering selection of comestibles and consumables, all just a mouse-click away from my virtual shopping basket. Get in! This is cool
11:02 a.m.
Realise that I am actually missing the human contact. It's always fun watching someone making a life-or-death decision over what colour of bog roll to purchase. Or sniggering at the shell-suited fatties loading up their trolleys with 10kg bags of frozen chips, 48 packs of BSE-burgers and crates of cheap lager. Not to mention the obvious charms of that pert young checkout girl.
11:09 a.m.
Gina is really getting on my tits. She is the "virtual shop assistant" who seems to pop up on my screen every thirty seconds, flashing her 100-megawatt grin and offering totally useless advice.
11:13 a.m.
I can feel my enthusiasm rapidly away as I'm confronted with yet another daunting selection of foodstuffs. I honestly had no idea that there were so many different types of cheese to choose from.
11:21 a.m.
Is it really strictly necessary to show a full screen, three dimensional image of a tin of sodding baked beans？ It took ages to download. The realisation dawns on me that in the same space of time I could have gone out to the corner shop, bought the sodding beans, heated them up, toasted some bread, eaten it and done the washing up. It's a disturbing thought.
11:46 a.m.
I finally complete my shopping and log off, but not before leaving my suggestion in the site's guest book that Gina is terminated immediately with extreme prejudice. It's actually taken me longer that if I had done it in the real world. No matter the fact that it will soon be delivered directly to my doorstep will more than make up for that.
11:49 a.m.
Back in bed. I'm trying to rest, but every time I close my eyes, I see a grainy image of a wedge of Wensleydale. Feel slightly nauseous.
12:16 p.m.
No sign of the delivery van yet.
12:55 p.m.
Still hasn't turned up.
1:39 p.m.
Getting a bit fed with waiting.
2:01 p.m.
I can feel malnutrition gnawing at my insides, so I decide to grab a sandwich from the corner shop. Unfortunately, I'm stuck behind some doddery old gent who's picking up six back issues of Incontinence magazine, and insists on paying for them with 2p pieces from an old sweetie jar.
2:08 p.m.
The delivery van called while I was in Mr. Singh's. The driver has left a postcard saying he can either return at 4:30, or instead I can collect my shopping from their collection depot. My brain is numb with hunger. I decide on the second option.
2:35 p.m.
The depot turns out to be on the other side of town, so I have to get there by bus. I pick up my four carrier bags, and stagger back to the bus stop, the cheese-wire-like handles of the bags digging deep into my flesh.
4:27 p.m.
I eventually get home precisely three minutes before the deliveryman was due to call back. I have blisters the size of 50p pieces on my hands, I've coughed up ￡1.95 on bus fares, and I've spent a great total of two hours and thirty-nine minutes doing my shopping. And I still forgot to get the milk.
The author of the passage will, most probably in the future, ______.
SECTION C NEWS BROADCAST
Directions: In this section you will hear everything ONCE ONLY. Listen carefully and then answer the questions that follow. At the end of each news item, you will be given 10 seconds to answer the questions.
听力原文： Here in Washington, the Clinton Administration is reaffirming the importance of close ties between the US and a united Canada. Mr Clinton discussed the outcome of the referendum Tuesday with Canadian Prime Minister Jean Chretien. VOA White House correspondent Debora Tate reports. "In the days ahead of the vote, the Clinton Administration had been careful to describe the referendum as an internal matter but had emphasized the importance of US ties with a united Canada. A day after the vote, it was the same message. White House spokesman Mike McCurry says President Clinton spoken by telephone with Canadian Prime Minister Jean Chretien after the ballots were counted Monday night." He reaffirmed the importance of the close relationship that exists between the United States and Canada and said once again how valuable that partnership is between the United States and a strong and united Canada. At the State Department, spokesman Nicholas Bums noted that the US border with Canada is the longest undefended border in the world and therefore he said it is critical for the United States to have a stable northern neighbor. Mr. Bums said the United States is fortunate to keep in place a free trade treaty and a defense alliance with a united Canada. Both pacts would have had to be negotiated with a separate Quebec, Debora Tate. VOA News at the White House.
If Quebec was separated from Canada, the two pacts with US ______.
There are more than forty universities in Britain--nearly twice as many as in 1960s. During the 1960s eight【C1】______new ones were founded, and ten other new ones were created by【C2】______old colleges of technologies into universities. In the same period the【C3】______of students more than doubled, from 70,000 to more than 200,000. By 1973 about 10% of men【C4】______from eighteen to twenty-one were in universities and about 5% of women. All the universities are【C5】______institutions. Each has its own governing councils.【C6】______some local businessmen and local politicians as【C7】______as a few academics. The state began to give【C8】______to them fifty years ago, and by 1970 cacti university derived nearly all its【C9】______from state grants. Students have to pay fees and living costs,【C10】______every student may receive from the local authority of the place where he lives a personal gram which is enough to pay his full【C11】______. including lodging and food unless his parents are【C12】______Most students【C13】______jobs in the summer for about six weeks, but they do not【C14】______do outside work during the【C15】______year. The Department of Education takes【C16】______for the payment which covers the whole【C17】______of the universities, but it does not exercise direct control. It can have an important influence【C18】______new developments through its power to【C19】______funds, but it takes the advice of the University Grants Committee, a body which is mainly【C20】______of academies.
【C1】
听力原文： According to a Justice Department report released in July 2003, the U. S. prison population surpassed 2 million for the first time-2,166,260 people were incarcerated in prisons or jails at the end of 2002 (the latest statistics available). Since 1990, the U. S. prison population, already the world's largest, has almost doubled.
About two -thirds of prisoners were in state and federal prisons, while the rest were in local jails. The report does not count all juvenile offenders, but noted that there were more than 10,000 inmates under age 18 held in adult prisons and jails in 2002. The number of women in federal and state prisons reached 97,491.
About 10. 4% of the entire African American male population in the United States aged 25 to 29 was incarcerated, by far the largest racial or ethnic group-by comparison, 2.4% of Hispanic men and 1.2% of white men in that same age group were incarcerated. According to a report by the Justice Policy Institute in 2002, the number of black men in prison has grown to five times the rate it was twenty years ago. Today, more African-American men are in jail than in college. In 2000 there were 791,600 black men in prison and 603,032 enrolled in college. In 1980, there were 143,000 black men in prison and 463,700 enrolled in college.
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