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 mak
A. The mortality rate for breast cancer dropped.
B. The mortality rate among black women has increased.
C. The number of reported breast cancer cases is rising.
D. A woman’s lifetime risk of breast cancer is rising.
Government officials reported three new cases of mad cow, bringing the total so far this year to 99. Last year, France recorded just 31 cases of the mad cow disease. The rising numbers are in part (1) a new testing program that focuses on cows that are most (2) . That program has (3) 39 cases. But still 60 new cases were identified in the usual way, (4) were found in 1999. Many scientists (5) that this year, five years after safety precautions were (6) , the number of cases would be (7) .
The rise in cases has (8) some scientists to question whether the disease can be transmitted in ways not yet understood. Scientists are still (9) the disease, first recognized in cows in 1986.
It appears that it is not caused by a bacteria, virus or fungus, but (10) infectious particles called prion, perhaps (11) a virus or other agent. The disease kills cells in the brain, (12) it spongy and fu
A. expect
B. expected
C. have expected
D. had expected
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