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Some heartening statistics were reported last year by the Journal of the National Cancer Institute: the mortality rate for breast cancer dropped nearly five percent between 1989 and 1992, the largest decline since 1950. The numbers were even more dramatic for young women: between 1987 and 1992, the mortality rate plummeted nearly 18 percent among white women younger than 40.
But discouraging news also surfaced: the mortality rate among black women has gone up, and the number of reported breast cancer cases is rising as well. Twenty years ago a woman s lifetime risk of breast cancer was one in 12; now it’s one in eight.
Nevertheless, we' re on the verge of a revolution in treating this disease. Researchers now have a clear picture of how a cancer cell becomes a tumor -- and how cells break free from a tumor and glide through the bloodstream to seed a new one in another part of the body. And they better understand how the female hormone estrogen makes breast cancer cells grow. "I think we're going to get this disease licked in my lifetime, "says Dr. Susan M. Love, director of the Revlon/U. C. L. A. Breast Cancer Center in Los Angeles.
Until that time, information is a woman’s most powerful tool. "A cancer diagnosis isn’t an emergency." Dr. Love says. "A patient should take time to educate herself and find out what the options are. "Most of all, a woman needs to re member that breast cancer is not death sentence, and that more than half of all women who develop it will live at least 15 years after their diagnosis.
Much of today’s. good news centers on refining old therapies. Here’s where we stand in treating breast cancer.
Surgery and Radiation. The most dramatic change in breast cancer treatment in the past 20 years is that mastectomy removal of the entire breast and often part of the underlying chest muscle -- is no longer considered the only safe course. The chances of survival are no greater after a mastectomy that after the less disfiguring lumpectomy -- in which just the tumor is removed and the breast is left intact -followed by radiation. "There are good reasons to choose mastectomy," says Dr. Larry Norton, chief of breast cancer medicine Manhattan’s Memorial Sloan-kettring Cancer Center. "But if you' re a good candidate for lumpectomy, increasing your chances of a cure isn’t one of those reasons."
For about 30 percent of women, mastectomy is the only reasonable choice -- for example, a woman with small breasts and a large tumor, or one whose tumor is disseminated throughout the breast. But concerns about which procedure to choose often have more to do with life-style. and attitudes. A lumpectomy requires radiation following surgery to kill any remaining cancer cells, which can mean outpatient visits five days a week for five to seven weeks. Scheduling could be a problem. Nancy Reagan, for instance, decided to have a mastectomy because radiation treatments would have taken too much time.
Many women, however, choose mastectomy out of fear and lack of information. Some patients are terrified of radiation and need to understand what it’s really all about, says Carol Fred, a clinical social worker at U. C. L. A’s Rhonda Fleming Mann Resource Center for Women with Cancer.
After a lumpectomy the machine that administers the treatment aims radioactive particles at the affected breast only. The treatments make most women tired and can sometimes leave the skin feeling sunburned. But the breast is not left radioactive.
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African bushmen are being given computers so they can use their skill at tracking wild animals to take part in a project that will help conservation and tourism.
The project is being run by Louis Liebenberg, a South African tracking expert, who has teamed up with Lindsay Steventon, a computer expert. They are equipping bushmen with handheld PalmPilot computers so they can record sightings of animals in the wild. The computers, known as Cyber Trackers, can then be taken to a base and the information down loaded onto a PC.
The project will create a remarkable database for scientists, who will have wildlife information c6llated throughout the year by bushmen whose knowledge of local animals is unrivalled.
To make the system easy to use for the largely illiterate bushmen, each type of animal is given a screen icon that cone spends to its appearance. Different breeds of the same animal are stored as sub menus, again using icons to note their distinguishing features.
Once an animal is spotted and its icon is pressed, the tracker can make further observations about the creature. Option include the pace at which it is moving, what it is eating, whether it is fighting or sleeping, the condition of its droppings and its apparent state of health.
If only the tracks of an animal are spotted, the bushmen can enter details of the species and which direction it was moving in. This may lead to later sightings and additional data. When an entry is to be committed to the PalmPilot’s memory, the bushman presses a button and a GPS receiver stamps a position on the data. To ensure accuracy the tracker has to estimate how far away the animal is so its position and not his is recorded.
The bushmen will also use the PalmPilots to record water levels and how plants are faring. Fluctuations in either can harm animal populations.
When the PalmPilot is attached to a base PC, the sightings can be downloaded and displayed on its screen as lines showing the movement and behaviour of individual animals as well as groups. This allows movement and feeding patterns to be examined.
Liebenberg hopes that as well as building a useful research tool these maps will give guidance on where tourists should be taken to optimise their chances of seeing elusive animals such as leopards and rhinos.
"A tracker could check on the PC where the latest sightings have been recorded and get a good idea where the best place would be to take tourists, "he says. "It could mean that instead of having to pay for three days in the bush, tourists need only budget for two days. "
The system is now being tested on a small scale but Liebenberg says that it has already given more insight into changes in the feeding patterns of the desert species of the endangered black rhino.
"What happened before was that a scientist would come down from a university for a few days a year, make some observations and that would be it -- the total knowledge of rhino eating patterns," he says, "With the Cyber Tracker the bushmen were able to log where the rhinos were, what they were eating, and how much of that food was left. We found the rhinos change food every couple of months as a new type of plant flourishes. It was always assumed they ate the same sorts of leaves and grass after the end of the dry season."
"This has huge implications for rhino populations because the trackers’data can show which other animals are eating what the rhinos feed on. In this case it was kudu, a common type of antelope, which is often served in restaurants. In future, the park ranger will be able to look at the rhino population and what they are eating and , if there are too many kudu in the area, he can cull some so there is less competition for food. It may sound harsh, but kudu are common and this relative of the black rhino is not, so you don’t want them to start losing condition. '
Steventon, w
A．didn't settleB．were settledC．settleD．once settled
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： President Clinton’s nominee for Defense Secretary, William Perrey, says he is very much concerned by the growing tension over North Korea’s nuclear program. The Sente Arms Services Committee held confirmation hearings Wednesday for Mr. Perrey who’s currently Deputy-Secretary of Defense, the number two post at the Pentagon. VOA’s David Swan re ports:
"Mr. Perrey told Senators the United States and the United Nations may have to decide very soon whether to impose sanctions on North Korea to bring the country in line with international nuclear standards. He says it will be a nightmare scenario if North Korea becomes a nuclear power. ' I' m unhappy with them having one nuclear bomb which they may al ready have, but I am even more concerned about the extensive program development they have on the way to develop while it couldn't be dozens of nuclear bombs. ' Mr. Perrey says he favors aggressive diplomacy to resolve the crisis and it is not anxious to use force though he supports the proposed deployment of the Patriot missiles defense batteries to South Korea. On another issue, Mr. Perrey says US troops should continue to join UN peace-keeping missions while any large American u nits should remain under US command. The Senate is expected to easily confirm Mr. Perrey to succeed out-going Defense Secretary Les Aspin who resigned in part over his handing of the mission in Somalia. David Swan, VOA news, the Defense Department."
Mr. William Perrey ______.
It can be concluded from the last paragraph that ______.
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