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Between now(June) and Labor Day, millions of American will offer up their bodies to the sun’s rays. A tan indicates health and beauty, and most sun worshippers will sacrifice a lot to achieve it—including themselves. With each hour, the sun’s ultraviolet radiation produces irreversible damage, hastening the development of unsightly wrinkles. And with each year on the beach or rooftop, the sunbather increases his risk of getting skin cancer.Skin cancer is by far the most common form of cancer. An estimated 400000 new cases will be detected this year in the United States, and almost all of them can be blamed on overexposure to the sun. Fortunately, most of these cancers are highly curable. But they can be disfiguring and take time to treat. For that reason, sun worshippers should treat deity with a good deal of awe.Sunburn, of course, is the initial hazard posed by UV radiation. Prolonged exposure to UV, however, interferes with the production of collagen fibers in the dermis, causing the skin to lose elasticity and creating premature wrinkles. Further deterioration of the dermis deprives the epidermis of nutrition and causes it to become thin and dry.Cancer is UV’s final insult. Short-wave radiant energy, especially from the UV-B band, breaks the strands of DNA. Enzymes work constantly to rearrange the DNA into proper sequence, but with repeated UV exposure, the repair process may eventually break down. Then the mutant DNA may produce a colony of cancer cells.But skin cancer may be avoided with a good dose of common sense. People with fair skin and blue eyes who burn easily stand the highest risk. Special danger spots are the parts of the body most constantly exposed to the sun, such as the cheeks, nose, lower lip and the ears. People who have already developed precancerous lesions or had one skin cancer growth stand a greatly increased chance of developing others. Dermatologists recommend avoiding the sun when it is most intense—between 11 a.m. and 3 p.m. Anyone who insists on sunbathing should use a good sun screen. These lotions and salves contain chemicals, such as paraaminobenzoic acid, that block out the burning UV-B radiation while permitting the tanning rays to reach the skin. Which of the following comes first as a possible damage by UV radiation（）
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People around the globe hit the height of their misery and depression in (51) age, a new international study suggests.The finding by British and American researchers was based on an analysis of well-being among approximately 2 million people in 80 nations. With few exceptions, the observation appears to apply across the board, regardless (52) gender, culture, geography, wealth, job history, education, and marriage or parental status."The scientific fact seems to be that happiness and positive mental health follow a giant ’U’ (53) through life, " said study author Andrew J. Oswald, a professor of economics at Warwick University in Warwickshire, England. "For the average person, it’s high when you’re 20, and then it slowly falls and bottoms out (54) your 40s. But the good news is that your (55) health picks up again, and eventually gets back to the high levels of our youth. "The finding was (56) on the pooling of several different sources of happiness data, including: two multi-decade happiness/satisfaction surveys (first launched in the 1970s), involving about 500,000 American and Western European men and women; four rounds of the 80-nation "World Values Survey" (57) between 1981 and 2004 in North America, Eastern and Western Europe, Asia, Africa, Australia, and Central and South America; and a 2004—2007 survey (58) nearly 1 million Britons.The bottom-line: For most people throughout the world, the highest probability for depression striking is around 44 years of (59) .In the United States, however, some as-yet unexplained (60) differences were observed, with happiness among men dipping the most in their early 50s, whereas women hit their Nadir around the age of 40.The researchers cautioned that cheerful people tend to live longer than unhappy (61) —a fact that might have skewed the overall finding. But they also suggested that evidence of a happiness (62) might simply reflect a midlife choice to give up long-held but no longer tenable aspirations, followed by a senior’s sense of gratitude for having successfully endured (63) others did not."That said, some might find it helpful simply to understand the general (64) of mental health as they go through their own life," said Oswald. "It might be useful for people to realize that if they are (65) in their 40s, this is normal, it is not exceptional. And just knowing this might help. " 54.（）
Between now(June) and Labor Day, millions of American will offer up their bodies to the sun’s rays. A tan indicates health and beauty, and most sun worshippers will sacrifice a lot to achieve it—including themselves. With each hour, the sun’s ultraviolet radiation produces irreversible damage, hastening the development of unsightly wrinkles. And with each year on the beach or rooftop, the sunbather increases his risk of getting skin cancer.Skin cancer is by far the most common form of cancer. An estimated 400000 new cases will be detected this year in the United States, and almost all of them can be blamed on overexposure to the sun. Fortunately, most of these cancers are highly curable. But they can be disfiguring and take time to treat. For that reason, sun worshippers should treat deity with a good deal of awe.Sunburn, of course, is the initial hazard posed by UV radiation. Prolonged exposure to UV, however, interferes with the production of collagen fibers in the dermis, causing the skin to lose elasticity and creating premature wrinkles. Further deterioration of the dermis deprives the epidermis of nutrition and causes it to become thin and dry.Cancer is UV’s final insult. Short-wave radiant energy, especially from the UV-B band, breaks the strands of DNA. Enzymes work constantly to rearrange the DNA into proper sequence, but with repeated UV exposure, the repair process may eventually break down. Then the mutant DNA may produce a colony of cancer cells.But skin cancer may be avoided with a good dose of common sense. People with fair skin and blue eyes who burn easily stand the highest risk. Special danger spots are the parts of the body most constantly exposed to the sun, such as the cheeks, nose, lower lip and the ears. People who have already developed precancerous lesions or had one skin cancer growth stand a greatly increased chance of developing others. Dermatologists recommend avoiding the sun when it is most intense—between 11 a.m. and 3 p.m. Anyone who insists on sunbathing should use a good sun screen. These lotions and salves contain chemicals, such as paraaminobenzoic acid, that block out the burning UV-B radiation while permitting the tanning rays to reach the skin. Why does the repair process of the DNA may finally fail（）
Between now(June) and Labor Day, millions of American will offer up their bodies to the sun’s rays. A tan indicates health and beauty, and most sun worshippers will sacrifice a lot to achieve it—including themselves. With each hour, the sun’s ultraviolet radiation produces irreversible damage, hastening the development of unsightly wrinkles. And with each year on the beach or rooftop, the sunbather increases his risk of getting skin cancer.Skin cancer is by far the most common form of cancer. An estimated 400000 new cases will be detected this year in the United States, and almost all of them can be blamed on overexposure to the sun. Fortunately, most of these cancers are highly curable. But they can be disfiguring and take time to treat. For that reason, sun worshippers should treat deity with a good deal of awe.Sunburn, of course, is the initial hazard posed by UV radiation. Prolonged exposure to UV, however, interferes with the production of collagen fibers in the dermis, causing the skin to lose elasticity and creating premature wrinkles. Further deterioration of the dermis deprives the epidermis of nutrition and causes it to become thin and dry.Cancer is UV’s final insult. Short-wave radiant energy, especially from the UV-B band, breaks the strands of DNA. Enzymes work constantly to rearrange the DNA into proper sequence, but with repeated UV exposure, the repair process may eventually break down. Then the mutant DNA may produce a colony of cancer cells.But skin cancer may be avoided with a good dose of common sense. People with fair skin and blue eyes who burn easily stand the highest risk. Special danger spots are the parts of the body most constantly exposed to the sun, such as the cheeks, nose, lower lip and the ears. People who have already developed precancerous lesions or had one skin cancer growth stand a greatly increased chance of developing others. Dermatologists recommend avoiding the sun when it is most intense—between 11 a.m. and 3 p.m. Anyone who insists on sunbathing should use a good sun screen. These lotions and salves contain chemicals, such as paraaminobenzoic acid, that block out the burning UV-B radiation while permitting the tanning rays to reach the skin. The word "deity" in the second paragraph refers to（）
Cancer develops over a long time, which means that you have years——typically decades——in which to hinder or promote it. Researchers are finding that what you eat may interfere with cancer growth at various stages. For example, certain foods can block the chemicals that initate cancer. Antioxidants(抗氧化剂), found in some vitamins and minerals, can snuff out oxygen free radicls (氧自由基), substances that are thought to make cells more susceptible to cancer, and they can even repair some of the cellular damage that has been done. And some food—wheat bran(麦,糠) in particular—has been shown to shrink precancerous(癌症前期的) cells.A recent review of 17 studies from 17 nations reveals that people who eat the most fruits and vegetables have about half the cancer raters of those who eat the least. In fact, some research suggests that frequent consumption of fruits and vegetables can cut the risk of lung cancer even in smokers.One of the most studied antioxidants in vegetables and fruits thought to protect against cancer is beta-carotene(β胡萝卜素), concentrated in deep green, yellow and orange vegetables such as carrots, sweet potatoes and spinach.Research also shows that beta-carotene can change in the body to retinoic acid (维生素A酸), a substance used in clinical trials to treat certain cancers.Here are some of the foods that contain cancer-fighting chemicals.Tomatoes. One of the compounds in tomatoes that is thought to reduce the risk of cancer is lycopene(蕃茄素), the pigment (色素) that makes tomatoes red. Lycopene, an antioxidant that is also found in watermelons and apricots, quenches certain cancer-triggering oxygen free fadicals. Healthy people with the most blood lycopene.Green Vegetables. A recent Italian study showed that dark-green leafy vegetables lower the risk of many cancer. Spinach, broccoli, kale and dark-green lettuces are chock-full of antioxidants, including beta-carotene, folate(叶酸) and lutein(叶黄素).A good rule of thumb(单凭经验的做法) : the darker the vegetable, the more antioxidants within.Pungent preventives(刺激性的预防物). A whole host of chemicals thought to have cancer-inhibiting properties have been identified in allium vegetables, which include garlic, onions and scallions(大葱). Animal studies show that many of these chemicals block carcinogens that have been linked to colon, stomach, lung and liver cancer. A study at Pennsylvania State University found that feeding rats various garlic extracts and preparations(配制好的食物) reduced mammary tumors by as much as 71 percent. In humans, studies suggest that those who eat more onions and garlic are less prone to gastrointestinal cancer.Research suggests that garlic compounds may even interfere with cancer progression. A recent German study found that ajoene, a garlic compound, is toxic to malignant cells. Garlic may also antagonize existing cancer by boosting(促进) immune functions, according to researchers at Loma Linda University School of Medicine. Their study, done on mice, found that garlic’s sulfur compounds increased the activity of macrophages and T-lymphocytes(淋巴细胞), two of the components of the immune system that destroy tumor ceils. Citrus fruit may be particularly effective in reducing the risk of pancreatic cancer.（）
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