单选题
Jamie Stephenson has seen firsthand
what modem genetic science can do for a family. When her son David was 2 years
old, a pediatrician noticed developmental delays and suspected fragile syndrome,
a hereditary form of mental retardation. A lab test confirmed the diagnosis, and
the Stephensons spent several years learning to live with it. When David was 6,
he visited a neurologist, who scribbled "fragile X" on an insurance-company
claim form. The company responded promptly—by canceling coverage for the entire
family of six. There is no medical treatment for fragile X, and none of David's
siblings had been diagnosed with the condition. "The company didn't care,"
Stephenson says. "They just saw a positive genetic test and said, 'You're out'.
" From the dawn of the DNA era, critics have worried that
genetic testing would create a "biological underclass"—a population of people
whose genes brand them as poor risks for employment, insurance, even marriage.
The future is arriving fast. Medical labs can now test human cells for hundreds
of anomalous genes. Besides tracking rare conditions, some firms now gauge
people's susceptibility to more common scourges. By unmasking inherited
mutations in p53 ( main story) and other, genes, the new tests can signal
increased risk of everything from breast, colon and prostate tumors to leukemia.
Many of the tests are still too costly for mass marketing, but that will change.
And as the Stephensons' story suggests, the consequences won't all be
benign. "This is bigger than race or sexual orientation," says Martha Volner,
health-policy director for the Alliance of Genetic Support Groups. "Genetic
discrimination is the civil-rights issue of the 21st century."
No one would argue that genetic tests are worthless. Used properly, they
can give people unprecedented power over their lives. Prospective parents who
discover they're silent carriers of the gene for a disease can make better-in
formed decisions about whether and how to have kids. Some genetic maladies can
be managed through medication and lifestyle changes once they're identified. And
while knowing that you're at special risk for cancer may be an emotional burden,
it can also alert you to the need for intensive monitoring. Jane Gorrell knows
her family is prone to colon cancer. Her father developed hundreds of
precancerous polyps back in the 1960s, and both she and her sister had the same
experience during the '70s. Their condition, has since been linked to a mutation
in the p53 gene—and Gorrell has learned, that one of her two children inherited
it. Though the child has suffered no symptoms, she gets frequent colon exams and
is helping researchers test a drug that could help save lives.
The catch is that no one can guarantee the privacy of genetic information.
Outside of large group plans, insurance companies often scour people's medical
records before extending coverage. And though employers face some restriction,
virtually any company with a benefits program can get access to workers' health
data. So can schools, adoption agencies and the military. Employees of Lawrence
Berkeley Laboratory (LBL), a large research institution owned by the Department
of Energy and operated by the University of California, recently discovered that
the organization had for three decades been quietly testing new hires blood and
urine samples for evidence of various conditions. "I can't say the information
was put to some incredibly harmful use, because we don't know what happened,"
says Vicki Laden, a San Francisco lawyer who has tried unsuccessfully to sue the
lab for civil fights violations. LBL recently stopped the
testing.
单选题
Questions
15-18
单选题Questions 1 to 5 are based on the following conversation.
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Every summer, the peacocks that roam
free within Whipsnade Wild Animal Park in Bedfordshire expose their magnificent
trains to the critical and often disdainful gaze of the hens. They re-enact the
mystery that tormented Charles Darwin to his dying day. how in this competitive
world, where nature—as Tennyson said—is red in tooth and claw, could birds have
evolved such an obvious extravagance? How do they get away with it? The
zoologist Marion Petrie and her colleagues of the Open University are now
exploiting the quasi-wild conditions of Whipsnade to try, a century after
Darwin's death, to settle the matter. Darwin argued that living
creatures came to be the way they are by evolution, rather than by special
creation; and that the principal mechanism of evolution was natural selection.
That is, in a crowded and hence competitive world, the individuals best suited
to the circumstances—the "fittest"—are the most likely to survive and have
offspring. But the implication is that fittest would generally
mean toughest, swiftest, cleverest, most alert. The peacock's tail, by contrast,
was at best a waste of space and in practice a severe encumbrance; and Darwin
felt obliged to invoke what he felt was a separate mechanism of evolution, which
he called "sexual selection". The driving mechanism was simply that females
liked in his words—"beauty for beauty's sake". But Darwin's
friend and collaborator, Alfred Russel Wallace, though in many ways more
"romantic" than Darwin, was in others even more Darwinian. "Beauty for beauty's
sake" he wanted nothing of. If peahens chose cocks with the showiest trains, he
felt, then it must be that they knew what they were about. The cocks must have
some other quality, which was not necessarily obvious to the human observer, but
which the hens themselves could appreciate. According to Wallace, then, the
train was not an end in itself, but an advertisement for some genuine
contribution to survival. Now, 100 years later, the wrangle is
still unresolved, for the natural behavior of peafowl is much harder to study
than might be imagined. But 200 birds at Whipsnade, which live like wild birds
yet are used to human beings, offer unique opportunities for study. Marion
Petrie and her colleagues at Whipsnade have identified two main questions.
First, is the premise correct—do peahens really choose the males with the
showiest trains? And, secondly, do the peacocks with the showiest trains have
some extra, genuinely advantageous quality, as Wallace supposed, or is it really
all show, as Darwin felt? In practice, the mature cocks display
in groups at a number of sites around Whipsnade, and the hens judge one against
the other. Long observation from hides, backed up by photographs, suggests that
the hens really do like the showiest males. What seems to count is the number of
eye, spots on the train, which is related to its length; the cocks with the most
eye-spots do indeed attract the most mates. But whether the
males with the best trains are also "better" in other ways remains to be pinned
down. William Hamilton of Oxford University has put forward the hypothesis that
showy male birds in general, of whatever species, are the most parasite free,
and that their plumage advertises their disease-free state. There is evidence
that this is so in other birds. But Dr. Petrie and her colleagues have not been
able to assess the internal parasites in the Whipsnade peacocks to test this
hypothesis. This year, however, she is comparing the offspring of cocks that
have in the past proved attractive to hens with the offspring of cocks that hens
find unattractive. Do the children of the attractive cocks grow faster? Are they
more healthy? If so, then the females' choice will be seen to be utilitarian
after all, just as Wallace predicted. There is a final twist to
this continuing story. The great mathematician and biologist R.A. Fisher in the
thirties proposed what has become known as "Fisher's Runaway". Just suppose, for
example, that for whatever reason—perhaps for a sound "Wallacian" reason—a
female first picks a male with a slightly better tail than the rest. The sons of
that mating will inherit their father's tail, and the daughters will inherit
their mother's predilection for long tails. This is how the runaway begins.
Within each generation, the males with the longest tails will get most mates and
leave most offspring; and the females' predilection for long tails will increase
commensurately. Modern computer models show that such a feedback mechanism would
alone be enough to produce a peacock's tail. Oddly, too, this would vindicate
Darwin's apparently fanciful notion—once the process gets going, the females
would indeed be selecting "beauty for beauty's
sake".
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The Lake District in north-west England
is an area remarkably little affected by industrialization. The principal
activity is still sheep-farming, as it has been for a thousand years, and many
ancient words like "fell" for "hill" and "tam" for "lake" are still in daily
use. In spite of its heavy rainfall and relative inaccessibility, its special
atmosphere and spectacular natural beauty combine to make this one of England's
favourite holiday areas at all seasons of the year. But at Christmas 1968, still
gripped by the fear that foot-and-mouth disease could spread to the hill flocks
and sweep like wildfire right up to the Scottish border, it was quieter than
ever before in this century. Luckily not a single farm had caught tile
infection, the nearest case having been an isolated one at Kendal several weeks
before. But every Lakeland farmer knows that one case among the unfenced hill
flocks on the fells could lead to complete annihilation of hundreds of thousands
of sheep and the virtual end of the district's principal industry; you cannot
replace sheep, acclimatized to their own part of the fell for generations, in
the same way that you can replace cattle in a field. Nobody
could remember a Christmas like it, especially Boxing Dab, which is
traditionally one of the big outdoor holidays of the Lakeland year. Normally
this is a day spent following the mountain packs of hounds, fell-walking and, if
the weather is propitious, skiing and skating, but this time there were none of
these things. Visitors were actively discouraged, and those who did come were
asked not to go on the fells, footpaths or bridleways or near farmland, while
motorists were requested not to drive on minor roads and to shun the smaller
valleys. The enterprising hotels which had earlier in the year decided to keep
open during the winter were by the end of October having a desperate time.
Hundreds of bookings had been cancelled and scores of dinner parties and young
farmers' reunions eliminated. All youth hostels were closed. At least one
climbing club, unable to climb, substituted a training programme of films and
simulated climbs on the more substantial municipal buildings.
The weather in the area was dry, crisp, windless and cold, in fact ideal
for brisk outdoor activities. But nobody was able to enjoy it. Everything was
stopped: hunting, walking, climbing, skiing, motor cycle trials, sporting events
of every description. All the seasonal dances, festivals, conferences,
shepherds' meets and a hundred and one, other social occasions abandoned. The
ice was bearing on some of the lakes but you could not go skating there.
Meanwhile the foxes, emboldened by an unprecedented freedom from harassment,
were stalking closer to the farms and the flocks of Christmas turkeys, while the
hounds sulked miserably in their kennels. Farmers are apt to
criticize some sections of the outdoor fraternity for their occasional
thoughtless behaviour, but the way that walkers, climbers, skiers, fishermen,
hunters and the rest went out of their way to help them at this time should
never be forgotten. The general public, locals and visitors alike, tried to give
the fell farmers a sporting chance, and this remarkable display of public spirit
was the one bright note in a very sad time.
单选题Questions 27-30
单选题[此试题无题干]
单选题Questions 6-10
The Guidford Four, freed last week after spending 15 years in prison for crimes they did not commit, would almost certainly have been executed for the pub bombing they were convicted of. They had the death penalty been in force at the time of their trial. They may now be a decent interval before the pro-hanging lobby, which has the support of the Prime Minister, makes another attempt to reintroduce the noose.
Reflections along these lines were about the only kind of consolation to be derived from this gross miscarriage of justice which is now to be the subject of a judicial inquiry. In the meantime, defense lawyers are demanding compensation and have in mind about half a million pounds for each of their clients.
The first three to be released--Mr. Gerald Conlon, Mr. Paddy Armstrong and Ms. Carole Richardson--left prison with the 34 pounds which is given to all departing inmates. The fourth, Mr. Paul Hill, was not released immediately but taken to Belfast, where he lodged an appeal against his conviction for the murder of a former British soldier. Since this conviction, too, was based on the now discredited statements allegedly made to the Survey police, he was immediately let out on bail. But he left empty-handed.
The immediate reaction to the scandal was renewed demand for the re-examination of the case against the Birmingham Six, who are serving life sentences for pub bombings in that city. Thus far the Home Secretary, Mr. Douglas Hurd, is insisting that the two cases are not comparable; that what is now known about the Guilford investigation has no relevance to what happened in Birmingham.
Mr. Hurd is right to the extent that there was a small--though flimsy and hotly-contested-- amount of crime evidence in the Birmingham case. The disturbing similarity is that the Birmingham Six, like the Guilford Four, claim that police officers lied and fabricated evidence to secure a conviction.
Making scapegoats of a few rogue police officers will not be sufficient to eliminate the Guilford miscarriage of justice. There are already demands that the law should be changed; first to make it impossible to convict on "confessions" alone; and secondly to require that statements from accused persons should only be taken in the presence of an independent third party to ensure they are not made under punishment.
It was also being noted this week that the Guilford Four owe their release more to the persistence of investigative reporters than to the diligence of either the judiciary or the police. Yet investigative reports--particularly on television--have recently been a particular target for the condemnation of Mrs. Thatcher and some of her ministers who seem to think that TV should be muzzled in the public interest and left to get on with soap operas and quiz shows.
单选题Like many people, I"ve always seen the Olympics as the "main" sporting event held every four years—the headline act—and the Paralyrnpics as something of an "add-on"—the supporting act. It you are not disabled yourself it is hard to understand some of the games and the athletes mobility problems.
But being in the host city for these Paralympics changed my perspective. I came to realize these athletes were nothing short of superheroes. Deprived of physical abilities that able-bodied people take for granted, they made up for them and then some. They tested their senses and the boundaries of physical ability to extremes that the Bolts and Phelpses of this world would never have to.
If some Olympic runners had to undergo a double-amputation, I wonder if they would strap two carbon fiber blades to their knees like Oscar Pistorius, also known as Blade Runner, of South Africa, and relearn everything that once came naturally.
If some Olympic swimming heroes suddenly went blind, would they have the courage to still surge through the water like Donovan Tildesley, not knowing when they would reach the end of the pool? Would any of us have the guts to turn around a life-changing experience like a car crash or bad rugby scrum. And not only get our lives back on track but then strive to be the best at a sport?
"What Paralympic sport would you do if you were disabled?" was a water-cooler question I posed today. It"s not something you would normally think about. You don"t watch TV as a kid aspiring to be a Paralympian. But it takes more than early mornings, training programs and special diets to get to the Paralympics. It takes a tragedy or loss that will have been grieved over, worked through and overcome.
Skiing is terrifying enough if you have all your faculties. Standing at the top of a ski slope, it"s a battle of wills for most people to launch themselves, but Canada"s Donovan Tildesley, who has been blind from birth, revealed to a China Daily reporter that not only did he already ski, but he also wanted to take it up competitively.
Superheroes indeed, each and every one. The Paralympics should be renamed the "Superlympics". It"s nothing to do with the equality denoted by the Greek "para", it"s about "super" ability, courage and strength that most of us, the top able-bodied athletes of the world included, will never have to muster.
It"s worth remembering that many Paralympians suffered horrific injuries while living life to the full. You don"t get paralyzed sitting at home playing video games. And having lived life to the full they are not prepared to stop. That"s the lesser talked about "Paralympic spirit".
I only hope that if life dealt me or my loved ones similar blows we would tackle them in the same way as these outstanding men and women.
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Biological clocks are physiological
systems that enable organisms to live in harmony with the rhythms of nature,
such as the cycles of day and night and of the seasons. Such biological "timers"
exist for almost every kind of periodicity throughout the plant and animal
world, but most of what is known about them comes from the study of circadian,
or daily, rhythms. Circadian rhythms cue typical daily behavior patterns even in
the absence of external cues such as sunrise, demonstrating that such patterns
depend on internal timers for their periodicity. No clock is
perfect, however. When organisms are deprived of the hints the world normally
provides, they display a characteristic "free-running" period of not quite 24
hours. As a result, free-running animals drift slowly out of phase with the
natural world. In experiments in which people are isolated for long periods of
time, they continue to eat and sleep on regular, but increasingly out-of-phase.
Such drift does not take place under normal circumstances, because external
hints reset the clocks each day. Light, particularly bright
fight, is believed to be the most powerful synchronizer of circadian rhythms.
Recent studies on humans have shown that the amount of artificial indoor fight
to which people are exposed per day can resynchronize the body's cycle of sleep
and wakefulness. People can inadvertently reset their body clocks to an
undesired cycle by such activities as shielding morning fight with shades and
heavy curtains or by reading in bed at night by bright lamp fight. Many
organisms also make use of rhythmic variations in temperature or other sensory
inputs to readjust their internal timers. When a clock's error becomes large,
complete resetting sometimes requires days. This phenomenon is well known to
long-distance air travelers as jet lag. Apparently, biological
clocks can exist in every cell and even in different parts of a cell. Hence, an
isolated piece of tissue removed from an organism—for example, the eye of a sea
slug—will maintain its own daily rhythm but will quickly adopt that of the whole
organism when restored to it. In the brains of most animals, a
master clock appears to exist that communicates its timing signals chemically to
the rest of the organism. For example, a brain removed from a moth pupa and
exposed to an artificial sunrise of one time zone, then implanted into the
abdomen of a headless pupa on a different time zone schedule, will cause the
second pupa to emerge at the time of day appropriate to the disconnected brain
floating in its abdomen. The clock in the brain triggers the release of a
hormone that switches on all the complex behavior involved in pupa emergence. In
hamsters, experiments have shown a master biological clock to be located in the
hypothalamus. Scientists believe that the biological clock in
humans is located in the hypothalamus, the part of the brain that regulates such
basic drives as hunger, thirst, and sexual desire. The biological clock itself
is believed to be a cluster of nerve cells called the suprachiasmatic
nucleus.
单选题Questions 1 to 5 are based on the following conversation.
单选题An eccentric is by definition someone whose behavior is abnormal, someone who refuses to conform to the accepted norms of his society. This, of course, immediately begs the question, "What is normal?" Most of us, after all, have our quirks and oddities. It may be a passion for entering newspaper competitions, a compulsion for collecting beer mats, a tendency to write indignant letters to the press on every conceivable subject. Eccentricity is the assertion of our individuality. Within most of us that urge is constantly in conflict with the contrary force. It is as though in the depths of our psyche we have two locomotives head-to- head on the same track, pushing against each other. One is called individualism and the other conformity, and in most of us it is conformity that is more powerful. The desire to be accepted, loved, appreciated, to feel at one with our fellows, is stronger than the desire to stand out in the crowd, to be our own man, to do our own thing.
Notice, for example, how people who have unusual hobbies, strong opinions, or unconventional behaviour, tend to congregate. They form clubs, hold meetings, and organize rallies where they can get together and discuss their common enthusiasms or problems. The important word is "common". They look for other people with whom they can share what in the normal run of events is regarded by relatives, friends and neighbors as an oddity. A crowd, even a small crowd, is reassuring.
Probably all of us recognize a tension within ourselves between the two forces of individualism and conformity, for at the same time that most of us are going with the crowd, we tend to resent any suggestion that this is what we are doing. We feel a self-conscious need to assert our individuality as when the belligerent man at the bar informs his small audience, "Well, I say what I think." Or the wary stranger to whom we have just been introduced announces, "You must take me as you find me. I don"t stand on ceremony."
Any of us can, at any time, reverse this trend. We can stoke the boiler of individualism, assert our own personality. Many people have made it to the top in their chosen professions. One example is Bob Dylan, the American singer, who has gone on record as saying, "When you feel in your gut what you are doing and then dynamically pursue it—don"t back down and don"t give up—then you"re going to mystify a lot of folk." But that self-conscious assertion of individuality is not eccentricity, at least not in the early stages. When a pop singer deliberately wears bizarre clothes to gain publicity, or a society hostess makes outrageous comments about her guests in order to get herself noticed in the gossip columns, that is not eccentricity. However, if the pop star and the society hostess perpetuate such activities until they become a part of themselves, until they are no longer able to return to what most of us consider "normal behaviour", then they certainly would qualify. For the most important ingredient of eccentricity is its naturalness. Eccentrics are not people who deliberately try to be odd, they simply are odd.
The true eccentric is not merely indifferent to public opinion, he is scarcely conscious at all. He simply does what he does, because of who he is. And this marks the eccentric as essentially different from, for example, enthusiasts, practical jokers, brilliant criminals, exhibitionists and recluses. These people are all very conscious of the world around them. Much of what they do, they do in reaction to the world in which they live. Some wish to make an impression on society, some wish to escape from society, but all are very much aware of society. The eccentric alone goes on his merry way regardless.
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单选题Questions 6 to 10 are based on the following news.
单选题Questions 16 to 20 are based on the following talk.
单选题Questions 11-15
I am afraid to sleep. I have been afraid to sleep for the last few weeks. I am so tired that, finally, I do sleep, but only for a few minutes. It is not a bad dream that wakes me; it is the reality I took with me into sleep. I try to think of something else. Immediately the woman in the marketplace comes into my mind.
I was on my way to dinner last night when I saw her. She was selling skirts. She moved with the same ease and loveliness I often saw in the women of Laos. Her long black hair was as shiny as the black silk of the skirts she was selling. In her hair, she wore three silk ribbons, blue, green, and white. They reminded me of my childhood and how my girlfriends and I used to spend hours braiding ribbons into our hair.
I don"t know the word for "ribbons", so I put my hand to my own hair and , with three fingers against my head , I looked at her ribbons and said "Beautiful. " She lowered her eyes and said nothing. I wasn"t sure if she understood me (I don"t speak Laotian very well).
I looked back down at the skirts. They had designs on them: squares and triangles and circles of pink and green silk. They were very pretty. I decided to buy one of those skirts, and I began to bargain with her over the price. It is the custom to bargain in Asia. In Laos bargaining is done in soft voices and easy moves with the sort of quiet peacefulness.
She smiled, more with her eyes than with her lips. She was pleased by the few words I was able to say in her language, although they were mostly numbers, and she saw that I understood something about the soft playfulness of bargaining. We shook our heads in disagreement over the price; then, immediately, we made another offer and then another shake of the head. She was so pleased that unexpectedly, she accepted the last offer I made. But it was too soon. The price was too low. She was being too generous and wouldn"t make enough money. I moved quickly and picked up two more skirts and paid for all three at the price set; that way I was able to pay her three times as much before she had a chance to lower the price for the larger purchase. She smiled openly then, and, for the first time in months, my spirit lifted. I almost felt happy.
The feeling stayed with me while she wrapped the skirts in a newspaper and handed them to me. When I left, though, the feeling left, too. It was as though it stayed behind in marketplace. I left tears in my throat. I wanted to cry. I didn"t, of course.
I have learned to defend myself against what is hard; without knowing it, I have also learned to defend myself against what is soft and what should be easy.
I get up, light a candle and want to look at the skirts. They are still in the newspaper that the woman wrapped them in. I remove the paper, and raise the skirts up to look at them again before I pack them. Something falls to the floor. I reach down and feel something cool in my hand. I move close to the candlelight to see what I have. There are five long silk ribbons in my hand, all different colors. The woman in the marketplace! She has given these ribbons to me!
There is no defense against a generous spirit, and this time I cry, and very hard, as if I could make up for all the months that I didn"t cry.
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