For several years, scientists have been testing a substance called interferon(干扰素), a possible wonder drug that is proving to be effective in treating a variety of diseases, including virus infections, bacterial infections, and cancers. To date, the new drug has no side effect of great influence to discourage its use. But in spite of its success, last year only one gram was produced in the entire world.
The reason for the shortage lies in the structure of interferon. A special protein, the interferon produced from one animal species cannot be used in treating another animal species. In other words, to treat human beings, only interferon produced by human beings may be used. The drug is produced by infecting white blood cells with a virus. Fortunately, it is so effective that the amount given to each patient each time is very small.
Unlike antibiotics (抗生素), interferon does not attack germs directly. Instead, it protects healthy cells from being infected, and prevents the reproduction of viruses within cells.
As you might conclude, one of the most special uses of interferon has been in the treatment of cancer. Dr. Hans Strander, a research physician at Sweden’s famous Karolinska Institute, has treated more than one hundred cancer patients with the new drug. Among a group of selected patients who had received operations for advanced cancer, half were given traditional treatments and the other half were given interferon. Among those treated with interferon 70 percent of them remained alive over three years, as compared with only 10 to 30 percent among those who had received the traditional treatments.
In the United States, a large-scale project supported by the American Cancer Society is now under way. If the experiment were successful, interferon could become one of the greatest medical discoveries of our time.
1.What is the difference between antibiotics and interferon?
A. Interferon has serious side effects, while antibiotics do not.
B. Antibiotics kill germs by attacking them directly, while interferon does not.
C. Antibiotics are very effective, while the effect of interferon is limited.
D. They are different in structure, although they are both proteins.
2. According to the passage, if 170 cancer patients received interferon treatment, how many of them would remain alive over three years?
A. About 30.
B. About 50.
C. About 120.
D. About 70.
3. The passage tells us that ________.
A. it is difficult to produce interferon in large quantities because of its special structure.
B. interferon is produced widely in lots of countries.
C. few of the patients who had received traditional treatments remained alive.
D. most of the patients who received interferon also needed traditional treatments.
While in Banff, make time for a walk around town. A special treat is to go up the mountainside on the Banff Gondola for a surprising view of the valley below. Here is The pines, whose cook has developed a special way of mixing foreign food such as caribou, wild boar, and reindeer with surprising sauces.
Best time to visit is during the off-season, from early May to mid-June, or in October. This way you can avoid sharing the high way with mobile homes which can be pulled by cars. But whatever the season, take some lunch with you from Banff, because there are only a few food stops on the road.
Forty minutes north of Banff, side by side with the Banff National Park, sits world-famous Lake Louise. This surprisingly small body of water is attractive with towering mountains around it. Glaciers, huge masses of ice, moving very slowly against rocks, produce what is called glacier rock flour, making its water dark to see. It is worth taking a walk around the grounds of the Chateau Lake Louise, another beauty, proud of its early 20th century history.
Back on the road, and it’s time to continue north past the astonishing Columbia Icefield, then turn off the highway and take the short road to the base of the Athabaska Glacier. You can rent ice cleats (夹板) and do some climbing or do a more pleasant snowmobile tour. Either way, you can enjoy endless beautiful sights.
Finally you’ll reach Jasper, the usual turning around the place for the Banff-Jasper loop (回路). It’s worth riding the Jasper Skytram, and be sure to visit the wonderful Jasper Park Lodge, also dating back to the 1920s. If you can have lunch there, do it. The restaurant has an adventurous menu and their wine list would put a smile on any visitor’s face.
1.According to the passage, The Pines is a ________.
A. place in which you can see many mobile homes
B. mountain where you can get a good view of the valley
C. town which happens to be near the Banff National park
D. restaurant where you can ask for some special kinds of food
2. What will probably happen when visitors come at the end of June?
A. They may have trouble finding a restaurant.
B. They may come across traffic jams.
C. They may travel more easily with cars.
D. They may do much more sightseeing.
3. Similar to the Chateau Lake Louise, ________.
A. the Banff National Park is to the west of Banff
B. the Columbia Icefield lies between Lake Louise and the Banff National Park
C. the Jasper Skytram has a history of more than 80 years
D. the Jasper Park Lodge was built in the 1920s
4.Besides the beautiful sights in Jasper Park Lodge, visitors to Jasper can enjoy themselves by ________.
A. taking the Jasper Skytram and eating in the restaurant
B. taking the Banff-Jasper loop and Jasper Skytram
完形填空（共20小题；每小题1分，满分20分）
阅读下面短文，掌握其大意，然后从下列各题所给的四个选项中，选出最佳选项。
Perhaps you’ve attended some parties. But like New York，where a party or dinner often __36__ business with pleasure, a Washington party is a __37__ part of the business of politics, the business of making __38__ connections.
Some Washington parties have a __39__ aura (气氛) about them, depending on who gives them and who is there, but most parties are open-house __40__ in fact, with the hosts not knowing most of the __41__ who are there.
I went to a few of these parties __42__ I wanted to see the inside of some of the Washington mansions (公馆) I had __43__ so much about. Almost every time during the evening some man would come close to talk with me __44__, we didn’t know each other at all. Such a __45__ exchange clearly proves “a gathering of friends” __46__ Washington party standards. You don’t even need an __47__ to attend many Washington parties. You just have to know about them. No Washington hostess would __48__ her servants to ask you who you were. Most of the bigger parties, those with 300 or 400 guests, __49__ to impress somebody, and Washingtonians __50__.
Most members of the Congress ,for example, __51__ middle-class backgrounds in smaller communities __52__ the country. They are dazzled (眼花缭乱的) by __53__. They are dazzled by big names. They are ready to help Washington __54__ hostesses. They go along with them because they are good friends or they don’t notice that they __55__ or they don’t care if they are.
1.. A. follows B. connects C. mixes D. goes
2.. A. daily B. necessary C. chief D. cheap
3.. A. still B. cruel C. mental D. important
4. A. social B. nervous C. terrible D. simple
5. A. events B. affairs C. conferences D. games
6. A. guests B. customers C. guards D. guides
7. A. so that B. in order that C. as if D. because
8. A. found B. noticed C. heard D. wrote
9. A. since B. though C. when D. whether
10. A. common B. strict C. public D. special
11. A. including B. comparing with C. according to D. depending on
12. A. invitation B. envelope C. instrument D. acceptance
13. A. refuse B. allow C. agree D. warn
14.A. are given B. give C. are supplied D. supply
15. A. easily forget B. hardly remember C. easily impress D. are easily impressed
16.A. hear from B. write to C. come from D. call out
17. A. over B. below C. between D. across
18.A. money B. equal C. freedom D. discussion
19. A. strange B. famous C. poor D. stupid
20. A. are using B. are being used C. are obeying D. are being obeyed
I remember ________ the job, but I forget the exact amount.
A. to be paid for B. being paid for
C. to be paid back D. being paid back
Fred seems very clear. His ideas led to _________ a pay raise.
A. his awarded B. his being awarded
C. him to award D. him to be awarded
--- How did you sleep last night?
--- Like a log. Never slept ________.
A. well B. worse C. badly D. better
