试卷介绍：
2008考研英语听课笔记（四）打包下载
部分试卷内容:
Passage 4
“I have great confidence that by the end of the decade we’ll know in vast detail how cancer cells arise,” says microbiologist Robert Weinberg, an expert on cancer. “But,” he cautions, “some people have the idea that once one understands the causes, the cure will rapidly follow. Consider Pasteur, he discovered the causes of many kinds of infections, but it was fifty or sixty years before cures were available.”
This year, 50 percent of the 910,000 people who suffer from cancer will survive at least five years. In the year 2000, the National Cancer Institute estimates, that figure will be 75 percent. For some skin cancers, the five-year survival rate is as high as 90 percent. But other survival statistics are still discouraging—13 percent for lung cancer, and 2 percent for cancer of the pancreas.
With as many as 120 varieties in existence, discovering how cancer works is not easy. The researchers made great progress in the early 1970s, when they discovered that oncogenes, which are cancer-causing genes, are inactive in normal cells. Anything from cosmic rays to radiation to diet may activate a dormant oncogene, but how remains unknown. If several oncogenes are driven into action, the cell, unable to turn them off, becomes cancerous.
2008考研英语听课笔记（四）打包下载
部分试卷内容:
Passage 4
“I have great confidence that by the end of the decade we’ll know in vast detail how cancer cells arise,” says microbiologist Robert Weinberg, an expert on cancer. “But,” he cautions, “some people have the idea that once one understands the causes, the cure will rapidly follow. Consider Pasteur, he discovered the causes of many kinds of infections, but it was fifty or sixty years before cures were available.”
This year, 50 percent of the 910,000 people who suffer from cancer will survive at least five years. In the year 2000, the National Cancer Institute estimates, that figure will be 75 percent. For some skin cancers, the five-year survival rate is as high as 90 percent. But other survival statistics are still discouraging—13 percent for lung cancer, and 2 percent for cancer of the pancreas.
With as many as 120 varieties in existence, discovering how cancer works is not easy. The researchers made great progress in the early 1970s, when they discovered that oncogenes, which are cancer-causing genes, are inactive in normal cells. Anything from cosmic rays to radiation to diet may activate a dormant oncogene, but how remains unknown. If several oncogenes are driven into action, the cell, unable to turn them off, becomes cancerous.
