摘要:希赛网英语考试频道为大家分享“2016年武汉理工大学考博英语真题”,更多考博英语相关信息,请关注希赛网英语考试频道。
“2016年武汉理工大学考博英语真题”小编正在努力更新中,请关注希赛网英语考试频道,以下为考博英语预测题库精选试题。
Among all the malignancies, lung cancer is the biggest killer; more than 100 000 Americans die of the disease. Giving up smoking is one of obvious ways to reduce the risk, but another answer may lie in the kitchen. According to a new report, even heavy smokers may be protected from developing lung cancer
by eating a daily portion of carrots, spinach or any other vegetable or fruit containing a form of vitamin A called carotene.
The finding, published in THE LANCET, is part of a long-range investigation of diet and disease. Since 1957, some American researchers have monitored the dietary habits and medical histories of 2 000 middle-aged men employed by the Western Electric Co. in Chicago. Led by Dr. Richard Shekelle of St. Luke’s Medical Center, the researchers recently began to sort out the links between the subjects’ dietary patterns and cancer. Other studies of animals and humans have suggested that vitamin A offer some protection against lung cancer. The correlation seemed logical, explains Shekelle, since vitamin A is essential for the growth of the epithelial tissue that lines the airways of the lungs. Vegetables: But the earlier research did not distinguish between the two different forms of the vitamin.
“Preformed” vitamin A, known as retinol, is found mainly in liver and dairy products like milk, cheese, butter and eggs. But vitamin A is also made in the body from carotene, which is abundant in a variety of vegetables and fruits, including carrots, spinach, squash, tomatoes, sweet potatoes and apples. In the study, Shekelle and his colleagues found little correlation between the incidence of lung cancer and the consumption of foods containing preformed vitamin A. But when they examined the data on carotene intake, they discovered a significant relationship. Among the 488 men who had the lowest level of carotene consumption, there were 14 cases of lung cancer, in a group of the same size that ate the most carotene ,only two cases developed. The apparent protective effect of carotene held up even for long-time smokers一but to a lesser degree.
Further studies will be necessary before the link between lung cancer and carotene can be firmly established. In the meantime, researchers warn against taking large numbers of vitamin A pills, because the tablets contain a form of the chemical that can be extremely toxic in high doses. Instead, they advise a well-balanced diet that includes goods rich in carotene. For a smoker, a half-cup of carrots every day might possibly make the difference between life and death.
71. The word " malignancy” ( Line 1, Para. 1) most probably refers to
A. cancer B. sickness C. vitamins D. disease
72. Preformed vitamin A is NOT found in
A. milk B.eggs C. apple D. cheese
73. Carotene is present in all of the following EXCEPT
A. tomatoes B.carrots C. squash D. butter
74. Among the groups studied, who had the most cases of lung cancer?
A. Those with the lowest level of carotene intake.
B.Those with the highest level of carotene intake.
C. Those who ate only foods containing carotene.
D. Those with the lowest intake of carrots.
75. What is needed to firmly establish the link between carotene and lung cancer?
A. Further study. B.More money.
C. More cases of lung cancer. D. More people willing to eat carrots.
小编推荐:
素材来源:网络
考博英语备考资料免费领取
去领取
2026年考博英语考试
具体时间待通知