单选题Passage2Can electricity cause cancer？In a society that literally runs on electric power，the very idea seems preposterous.But for more than a decade，a growing band of scientists and journalists has pointed to studies that seem to link exposure to electromagnetic fields with increased risk of leukemia and other malignancies.The implications are unsettling，to say the least，since everyone comes into contact with such fields，which are generated by everything electrical，from power lines and antennas to personal computers and micro-wave ovens. Because evidence on the subject is inconclusive and often contradictory，it has been hard to decide whether concern about the health effects of electricity is legitimate-or the worst kind of paranoia.Now the alarmists have gained some qualified support from the U.S.Environmental Protection Agency. In the executive summary of a new scientific review，released in draft form late last week，the EPA has put forward what amounts to the most serious government warning to date.The agency tentatively concludes that scientific evidencesuggests a casual link”between extremely low-frequency electromagnetic fields-those having very long wave-lengths-and leukemia，lymphoma and brain cancer，While the report falls short of classifying ELF fields as probable carcinogens，it does identify the common 60-hertz magnetic field asa possible，but not proven，cause of cancer in humans.”The report is no reason to panic-or even to lost sleep.If there is a cancer risk，it is a small one.The evidence is still so controversial that the draft stirred a great deal of debate within the Administration，and the EPA released it over strong objections from the Pentagon and the White House.But now no one can deny that the issue must be taken seriously and that much more research is needed.At the heart of the debate is a simple and well-understood physical phenomenon: When an electric current passes through a wire, it generates an electromagnetic field that exerts forces on surrounding objects. For many years, scientists dismissed any suggestion that such forces might be harmful, primarily because they are so extraordinarily weak. The ELF magnetic field generated by a video terminal measures only a few milligauss, or about one-hundredth the strength of the earth' sown magnetic field, the electric fields surrounding a power line can be as high as 10 kilovolts permeter, but the corresponding field induced in human cells will be only about 1 millivolt per meter. This is far less than the electric fields that the cells themselves generate.How could such minuscule forces pose a health danger? The consensus used to be that they could not, and for decades, scientists concentrated on more powerful kinds of radiation, like X-rays, that pack sufficient wallop to knock electrons out of the molecules that make up the human body. Suchionizingradiations have been clearly linked to increased cancer risks and there are regulations to control emissions.But epidemiological studies, which find statistical associations between sets of data, do not prove cause and effect. Though there is a body of laboratory work showing that exposure to ELF fields can have biological effects on animal tissues,a mechanism by which those effects could lead to cancerous growths has never been found.The Pentagon is far from persuaded. In a blistering 33-page critique of the EPA report, Air Force scientists charge its authors with having biased the entire documenttoward proving a link. Our reviewers are convinced that there is no suggestion that(electromagnetic fields) present in the environment induce or promote cancer,the Air Force concludes.It is astonishing that the EPA would lend its imprimatur on this report.Then Pentagon's concern is understandable. There is hardly a unit of the modern military that does not depend on the heavy use of some kind of electronic equipment, from huge ground-based radar towers to the defense systems built into every warship and plane.The view-point of the EPA is_______.Athere is casual link between electricity and cancerBelectricity really affects cancerCcontroversialDlow frequency electromagnetic field is a possible cause of cancer
单选题
Passage2Can electricity cause cancer？In a society that literally runs on electric power，the very idea seems preposterous.But for more than a decade，a growing band of scientists and journalists has pointed to studies that seem to link exposure to electromagnetic fields with increased risk of leukemia and other malignancies.The implications are unsettling，to say the least，since everyone comes into contact with such fields，which are generated by everything electrical，from power lines and antennas to personal computers and micro-wave ovens. Because evidence on the subject is inconclusive and often contradictory，it has been hard to decide whether concern about the health effects of electricity is legitimate-or the worst kind of paranoia.Now the alarmists have gained some qualified support from the U.S.Environmental Protection Agency. In the executive summary of a new scientific review，released in draft form late last week，the EPA has put forward what amounts to the most serious government warning to date.The agency tentatively concludes that scientific evidencesuggests a casual link”between extremely low-frequency electromagnetic fields-those having very long wave-lengths-and leukemia，lymphoma and brain cancer，While the report falls short of classifying ELF fields as probable carcinogens，it does identify the common 60-hertz magnetic field asa possible，but not proven，cause of cancer in humans.”The report is no reason to panic-or even to lost sleep.If there is a cancer risk，it is a small one.The evidence is still so controversial that the draft stirred a great deal of debate within the Administration，and the EPA released it over strong objections from the Pentagon and the White House.But now no one can deny that the issue must be taken seriously and that much more research is needed.At the heart of the debate is a simple and well-understood physical phenomenon: When an electric current passes through a wire, it generates an electromagnetic field that exerts forces on surrounding objects. For many years, scientists dismissed any suggestion that such forces might be harmful, primarily because they are so extraordinarily weak. The ELF magnetic field generated by a video terminal measures only a few milligauss, or about one-hundredth the strength of the earth' sown magnetic field, the electric fields surrounding a power line can be as high as 10 kilovolts permeter, but the corresponding field induced in human cells will be only about 1 millivolt per meter. This is far less than the electric fields that the cells themselves generate.How could such minuscule forces pose a health danger? The consensus used to be that they could not, and for decades, scientists concentrated on more powerful kinds of radiation, like X-rays, that pack sufficient wallop to knock electrons out of the molecules that make up the human body. Suchionizingradiations have been clearly linked to increased cancer risks and there are regulations to control emissions.But epidemiological studies, which find statistical associations between sets of data, do not prove cause and effect. Though there is a body of laboratory work showing that exposure to ELF fields can have biological effects on animal tissues,a mechanism by which those effects could lead to cancerous growths has never been found.The Pentagon is far from persuaded. In a blistering 33-page critique of the EPA report, Air Force scientists charge its authors with having biased the entire documenttoward proving a link. Our reviewers are convinced that there is no suggestion that(electromagnetic fields) present in the environment induce or promote cancer,the Air Force concludes.It is astonishing that the EPA would lend its imprimatur on this report.Then Pentagon's concern is understandable. There is hardly a unit of the modern military that does not depend on the heavy use of some kind of electronic equipment, from huge ground-based radar towers to the defense systems built into every warship and plane.The view-point of the EPA is_______.
A
there is casual link between electricity and cancer
B
electricity really affects cancer
C
controversial
D
low frequency electromagnetic field is a possible cause of cancer
参考解析
解析：
相关考题：
The doctor told him smoking too much would ___________ his health and even cause lung cancer. A.affectB.effectC.affirmD.effort
Women have fought long and hard ______ equally in language as well as in society, because they know that changes in language can cause changes in attitudes. A. be treatedB. to be treatedC. being treatedD. treated
Unequal distribution of wealth may cause (separations) in society. 选择能代替括号里的选项A、splitsB、troubleC、contradictionsD、divisions
共用题干第一篇U. S. Blacks Hard-hit by CancerDeath rates for cancer are falling for all Americans,but black Americans are still more likely to die of cancer than whites,the American Cancer Society said Monday.In a special report on cancer and blacks,the organization said blacks are usually diagnosed with cancer later than whites,and they are more likely to die of the disease.This could be because of unequal（不平等的）access to medical care, because blacks are more likely to have other diseases as well,and perhaps because of differences in the biology（生物学）of the cancer itself, the report added."In general,black Americans have less hope of surviving five years after diagnosis than whites for all cancer sites and all stages of diagnosis,"the report said,"In describing cancer statistics for black Americans,this report recognizes that many of the differences associated with race may be caused by unfair social and economic differences and unequal access to medical care."The cancer society said blacks should be encouraged to get check-ups（体格检查） earlier,when cancer is more treatable,and it said more research is needed to see if biological differences play a role."The new statistics emphasize the continuing importance of wiping out these unfair social differences through public policy and education efforts,"the organization said in a statement.But it also noted a drop in cancer death rates."Cancer death rates in both sexes for all sites combined have dropped greatly among black Americans since 1992,as have incidence rates（发生率）,"said the report. Cancer is more treatable if it is detectedA:in an early stage. B:in a late stage.C:all of a sudden. D:together with other diseases.
共用题干1. Do you know a child who survived leukemia（白血病）?Do you have a mother , sister or aunt whose breast cancer was found early thanks to a mammogram（乳腺X光照片）?Do you have a friend or coworker who quit smoking to reduce their risk of lung cancer? Each of these individuals benefited from the American Cancer Society's research program.2.Each day scientists supported by the American Cancer Society work to find breakthroughs that will take US one step closer to a cure.The American Cancer Society has long recognized that research holds the ultimate answers to the prevention,diagnosis and treatment of cancer.3.As the largest source of nonprofit cancer research funds in the United States,the American Cancer Society devotes over $100 million each year to research.Since 1946,they've invested more than $2. 4 billion in research. The investment has paid rich dividends（回报、效益）.In 1946,only one in four cancer patients was alive five years after diagnosis;today 60 percent live longer than five years.4.Investigators and health professionals in universities,research institutes and hospitals throughout the country receive grants from the American Cancer Society.Of the more than 1,300 new applications received each year,only 11 percent can be funded.If the American Cancer Society had more money available for research funding,nearly 200 more applications considered outstanding could be funded each year.5.You can help fund more of these applications by participating in the American Cancer Society Relay（接力）for Life,a team event to fight cancer. More funding means more cancer breakthroughs and more lives being saved.To learn more,call Donna Hood,chair with the Neosho Relay for Life of the American Cancer Society at 451-4880.More cancer breakthroughs can be made with__________.A:lack of fundingB:many cancer patientsC:more lives being savedD:more than five yearsE:the ultimate answers F: more funding
共用题干第一篇U. S. Blacks Hard-hit by CancerDeath rates for cancer are falling for all Americans,but black Americans are still more likely to die of cancer than whites,the American Cancer Society said Monday.In a special report on cancer and blacks,the organization said blacks are usually diagnosed with cancer later than whites,and they are more likely to die of the disease.This could be because of unequal（不平等的）access to medical care, because blacks are more likely to have other diseases as well,and perhaps because of differences in the biology（生物学）of the cancer itself, the report added."In general,black Americans have less hope of surviving five years after diagnosis than whites for all cancer sites and all stages of diagnosis,"the report said,"In describing cancer statistics for black Americans,this report recognizes that many of the differences associated with race may be caused by unfair social and economic differences and unequal access to medical care."The cancer society said blacks should be encouraged to get check-ups（体格检查） earlier,when cancer is more treatable,and it said more research is needed to see if biological differences play a role."The new statistics emphasize the continuing importance of wiping out these unfair social differences through public policy and education efforts,"the organization said in a statement.But it also noted a drop in cancer death rates."Cancer death rates in both sexes for all sites combined have dropped greatly among black Americans since 1992,as have incidence rates（发生率）,"said the report. Since 1992,cancer death rates among black AmericansA:have been going up and down. B:have remained stable.C:have increased. D:have fallen.
共用题干1. Do you know a child who survived leukemia（白血病）?Do you have a mother , sister or aunt whose breast cancer was found early thanks to a mammogram（乳腺X光照片）?Do you have a friend or coworker who quit smoking to reduce their risk of lung cancer? Each of these individuals benefited from the American Cancer Society's research program.2.Each day scientists supported by the American Cancer Society work to find breakthroughs that will take US one step closer to a cure.The American Cancer Society has long recognized that research holds the ultimate answers to the prevention,diagnosis and treatment of cancer.3.As the largest source of nonprofit cancer research funds in the United States,the American Cancer Society devotes over $100 million each year to research.Since 1946,they've invested more than $2. 4 billion in research. The investment has paid rich dividends（回报、效益）.In 1946,only one in four cancer patients was alive five years after diagnosis;today 60 percent live longer than five years.4.Investigators and health professionals in universities,research institutes and hospitals throughout the country receive grants from the American Cancer Society.Of the more than 1,300 new applications received each year,only 11 percent can be funded.If the American Cancer Society had more money available for research funding,nearly 200 more applications considered outstanding could be funded each year.5.You can help fund more of these applications by participating in the American Cancer Society Relay（接力）for Life,a team event to fight cancer. More funding means more cancer breakthroughs and more lives being saved.To learn more,call Donna Hood,chair with the Neosho Relay for Life of the American Cancer Society at 451-4880.Many outstanding applications are turned down each year for__________. A:lack of fundingB:many cancer patientsC:more lives being savedD:more than five yearsE:the ultimate answers F: more funding
共用题干1. Do you know a child who survived leukemia（白血病）?Do you have a mother , sister or aunt whose breast cancer was found early thanks to a mammogram（乳腺X光照片）?Do you have a friend or coworker who quit smoking to reduce their risk of lung cancer? Each of these individuals benefited from the American Cancer Society's research program.2.Each day scientists supported by the American Cancer Society work to find breakthroughs that will take US one step closer to a cure.The American Cancer Society has long recognized that research holds the ultimate answers to the prevention,diagnosis and treatment of cancer.3.As the largest source of nonprofit cancer research funds in the United States,the American Cancer Society devotes over $100 million each year to research.Since 1946,they've invested more than $2. 4 billion in research. The investment has paid rich dividends（回报、效益）.In 1946,only one in four cancer patients was alive five years after diagnosis;today 60 percent live longer than five years.4.Investigators and health professionals in universities,research institutes and hospitals throughout the country receive grants from the American Cancer Society.Of the more than 1,300 new applications received each year,only 11 percent can be funded.If the American Cancer Society had more money available for research funding,nearly 200 more applications considered outstanding could be funded each year.5.You can help fund more of these applications by participating in the American Cancer Society Relay（接力）for Life,a team event to fight cancer. More funding means more cancer breakthroughs and more lives being saved.To learn more,call Donna Hood,chair with the Neosho Relay for Life of the American Cancer Society at 451-4880.The American Cancer Society's research program has benefited________.A:lack of fundingB:many cancer patientsC:more lives being savedD:more than five yearsE:the ultimate answers F: more funding
共用题干第一篇U. S. Blacks Hard-hit by CancerDeath rates for cancer are falling for all Americans,but black Americans are still more likely to die of cancer than whites,the American Cancer Society said Monday.In a special report on cancer and blacks,the organization said blacks are usually diagnosed with cancer later than whites,and they are more likely to die of the disease.This could be because of unequal（不平等的）access to medical care, because blacks are more likely to have other diseases as well,and perhaps because of differences in the biology（生物学）of the cancer itself, the report added."In general,black Americans have less hope of surviving five years after diagnosis than whites for all cancer sites and all stages of diagnosis,"the report said,"In describing cancer statistics for black Americans,this report recognizes that many of the differences associated with race may be caused by unfair social and economic differences and unequal access to medical care."The cancer society said blacks should be encouraged to get check-ups（体格检查） earlier,when cancer is more treatable,and it said more research is needed to see if biological differences play a role."The new statistics emphasize the continuing importance of wiping out these unfair social differences through public policy and education efforts,"the organization said in a statement.But it also noted a drop in cancer death rates."Cancer death rates in both sexes for all sites combined have dropped greatly among black Americans since 1992,as have incidence rates（发生率）,"said the report. Which may NOT be a reason for higher cancer death rates among US blacks?A:Unequal access to medical care.B:Greater probability of having other diseases.C:Differences in the biology of the cancer.D:Early diagnosis.
共用题干第一篇U. S. Blacks Hard-hit by CancerDeath rates for cancer are falling for all Americans,but black Americans are still more likely to die of cancer than whites,the American Cancer Society said Monday.In a special report on cancer and blacks,the organization said blacks are usually diagnosed with cancer later than whites,and they are more likely to die of the disease.This could be because of unequal（不平等的）access to medical care, because blacks are more likely to have other diseases as well,and perhaps because of differences in the biology（生物学）of the cancer itself, the report added."In general,black Americans have less hope of surviving five years after diagnosis than whites for all cancer sites and all stages of diagnosis,"the report said,"In describing cancer statistics for black Americans,this report recognizes that many of the differences associated with race may be caused by unfair social and economic differences and unequal access to medical care."The cancer society said blacks should be encouraged to get check-ups（体格检查） earlier,when cancer is more treatable,and it said more research is needed to see if biological differences play a role."The new statistics emphasize the continuing importance of wiping out these unfair social differences through public policy and education efforts,"the organization said in a statement.But it also noted a drop in cancer death rates."Cancer death rates in both sexes for all sites combined have dropped greatly among black Americans since 1992,as have incidence rates（发生率）,"said the report. Public policy and education efforts may help to do away withA:death rates. B:various cancers.C:unfair social differences. D:biological differences.
共用题干第一篇A New Strategy to Overcome Breast CancerPost-menopausal（绝经后的）women who walk for an hour a day can cut their chance of breast cancer significantly,a study has suggested.The report,which followed 73,000 women for 17 years,found walking for at least seven hours a week lowered the risk of the disease.The American Cancer Society team said this was the first time reduced risk was specifically linked to walking.UK experts said it was more evidence that lifestyle influenced cancer risk.A recent poll for the charity Ramblers found a quarter of adults walk for no more than an hour a week, but being active is known to reduce the risk of a number of cancers.This study,,published in Cancer Epidemiology,Biomarkers&Prevention,followed 73,615 women out of 97,785 aged 50-74 who had been recruited by the American Cancer Society between 1992 and 1993,so it could monitor the incidence of cancer in the group.They were asked to complete questionnaires on their health and on how much time they were active and participating in activities such as walking , swimming and aerobics（有氧运动）and how much time they spent sitting,watching television or reading.They completed the same questionnaires at, two-year intervals between 1997 and 2009.Of the women,47%said walking was their only recreational activity.Those who walked for at least seven hours per week had a 14%lower risk of breast cancer compared to those who walked three or fewer hours per week.Dr.Alpa Patel,a senior epidemiologist at the American Cancer Society in Atianta Georgia,who led the study,said:"Given that more than 60% of women report some daily walking,promoting walking as a healthy leisure-time activity could be an effective strategy for increasing physical activity amongst post-menopausal women.We were pleased to find that without any other recreational activity,just walking one hour a day was associated with a lower risk of breast cancer in these women." " More strenuous（紧张的） and longer activities lowered the risk even more."Baroness Delyth Morgan,chief executive of Breast Cancer Campaign,said:"This study adds further evidence that our lifestyle choices can play a part in influencing the risk of breast cancer and even small changes incorporated into our normal day-to-day activity can make a difference."She added:"We know that the best weapon to overcoming breast cancer is the ability to stop it occurring in the first place.The challenge now is how we turn these findings into action and identify other sustainable lifestyle changes that will help us prevent breast cancer."Dr.Alpa Patel was______.A:chief editor of Cancer EpidemiologyB:chair of the American Cancer SocietyC:chief executive of Breast Cancer CampaignD:head of the survey study
共用题干US Blacks Hard-hit by CancerDeath rates for cancer are falling for all Americans,but black Americans are still more likely to die of cancer than whites,the American Cancer Society said Monday.In a special report on cancer and blacks,the organization said blacks are usually diagnosed with cancer later than whites,and they are more likely to die of the disease.This could be because of unequal access to medical care,because blacks are more likely to have other diseases like diabetes as well,and perhaps because of differences in the biology of the cancer itself,the report added.“In general,African Americans have less likelihood of surviving five years after diagnosis than whites for all cancer sites and all stages of diagnosis,”the report said.“In describing cancer statistics for African Americans,this report recognizes that socioeconomic disparities and unequal access to medical care may underlie many of the differences associated with race.”The Cancer Society said blacks should be encouraged to get check-ups earlier,when cancer was more treatable,and it said more research is needed to see if biological differences play a role.“The new statistics emphasize the continuing importance of eliminating these social disparities through public policy and education efforts,”the organization said in a statement.But it also noted a drop in cancer death rates.“Cancer death rates in both sexes for all sites combined have declined substantially among black Americans since 1992,as have incidence rates,”said the report.“Increased efforts to improve economic conditions in combination with education about the relationship of lifestyle choices to cancer could further reduce the burden of cancer among African Americans.” About 36 million Americans describe themselves as black,representing about 12 percent of the population. Black Americans are more likely to die of cancer than________.A:.people in other countriesB:.white AmericansC:.all other AmericansD:.their ancestors
共用题干第二篇US Blacks Hard-hit by CancerDeath rates for cancer are falling for all Americans,but black Americans are still more likely to die ofcancer than whites,the American Cancer Society said Monday.In a special report on cancer and blacks, the organization said blacks are usually diagnosed with cancerlater than whites,and they are more likely to die of the disease.This could be because of unequal access to medical care,because blacks are more likely to have otherdiseases like diabetes as well,and perhaps because of differences in the biology of the cancer itself,the report added."In general,African Americans have］ess likelihood of surviving five years after diagnosis than whites forall cancer sites and all stages of diagnosis,"the report said."In describing cancer statistics for African Americans,this report recognizes that socioeconomic dispari-ties and unequal access to medical care may underlie many of the differences associated with race."The Cancer Society said blacks should be encouraged to get check-ups earlier,when cancer is moretreatable,and it said more research was needed to see if biological differences play a role.Public policy and education efforts may help to do away with________.A:death rates B:various cancersC:unfair social differences D:biological differences
共用题干第二篇US Blacks Hard-hit by CancerDeath rates for cancer are falling for all Americans,but black Americans are still more likely to die ofcancer than whites,the American Cancer Society said Monday.In a special report on cancer and blacks, the organization said blacks are usually diagnosed with cancerlater than whites,and they are more likely to die of the disease.This could be because of unequal access to medical care,because blacks are more likely to have otherdiseases like diabetes as well,and perhaps because of differences in the biology of the cancer itself,the report added."In general,African Americans have］ess likelihood of surviving five years after diagnosis than whites forall cancer sites and all stages of diagnosis,"the report said."In describing cancer statistics for African Americans,this report recognizes that socioeconomic dispari-ties and unequal access to medical care may underlie many of the differences associated with race."The Cancer Society said blacks should be encouraged to get check-ups earlier,when cancer is moretreatable,and it said more research was needed to see if biological differences play a role.Since 1992,cancer death rates among black Americans_______.A:have been going up and down B:have remained stableC:have increased D:have fallen
共用题干US Blacks Hard-hit by CancerDeath rates for cancer are falling for all Americans,but black Americans are still more likely to die of cancer than whites,the American Cancer Society said Monday.In a special report on cancer and blacks,the organization said blacks are usually diagnosed with cancer later than whites,and they are more likely to die of the disease.This could be because of unequal access to medical care,because blacks are more likely to have other diseases like diabetes as well,and perhaps because of differences in the biology of the cancer itself,the report added.“In general,African Americans have less likelihood of surviving five years after diagnosis than whites for all cancer sites and all stages of diagnosis,”the report said.“In describing cancer statistics for African Americans,this report recognizes that socioeconomic disparities and unequal access to medical care may underlie many of the differences associated with race.”The Cancer Society said blacks should be encouraged to get check-ups earlier,when cancer was more treatable,and it said more research is needed to see if biological differences play a role.“The new statistics emphasize the continuing importance of eliminating these social disparities through public policy and education efforts,”the organization said in a statement.But it also noted a drop in cancer death rates.“Cancer death rates in both sexes for all sites combined have declined substantially among black Americans since 1992,as have incidence rates,”said the report.“Increased efforts to improve economic conditions in combination with education about the relationship of lifestyle choices to cancer could further reduce the burden of cancer among African Americans.” About 36 million Americans describe themselves as black,representing about 12 percent of the population. Which may NOT be a reason for higher cancer death rates among US blacks?A: Unequal access to medical care.B: Greater probability of having other diseases.C: Differences in the biology of the cancer.D:.Early diagnosis.
共用题干第二篇US Blacks Hard-hit by CancerDeath rates for cancer are falling for all Americans,but black Americans are still more likely to die ofcancer than whites,the American Cancer Society said Monday.In a special report on cancer and blacks, the organization said blacks are usually diagnosed with cancerlater than whites,and they are more likely to die of the disease.This could be because of unequal access to medical care,because blacks are more likely to have otherdiseases like diabetes as well,and perhaps because of differences in the biology of the cancer itself,the report added."In general,African Americans have］ess likelihood of surviving five years after diagnosis than whites forall cancer sites and all stages of diagnosis,"the report said."In describing cancer statistics for African Americans,this report recognizes that socioeconomic dispari-ties and unequal access to medical care may underlie many of the differences associated with race."The Cancer Society said blacks should be encouraged to get check-ups earlier,when cancer is moretreatable,and it said more research was needed to see if biological differences play a role.Which may NOT be a reason for higher cancer death rates among US blacks?A:Unequal access to medical care. B:Greater probability of having other diseases.C:Differences in the biology of the cancer. D:Early diagnosis.
单选题阅读理解：请根据短文内容，为每题确定l个最佳选项。 A New Strategy to Overcome Breast Cancer。 Post-menopausal（绝经后）women who walk for an hour a day can cut their chance of breast cancer significantly,a study has suggested. The report, which followed 73,000 women for 17 years,found walking for at least seven hours a week lowered the risk of the disease.The American Cancer Society team said this was the first time reduced risk was specifically linked to walking. UK experts said it was more evidence that lifestyle influenced cancer risk. A recent poll for the charity Ramblers a quarter of adults walk for no more than an hour a week,but being active is known to reduce the risk of a number of cancers.This study, published in Cancer Epidemiology,BiomarkersPrevention,followed 73.615 women out of 97,785 aged 50-74 who had been recruited by the American Cancer Society between 1992 and 1993,so it could monitor the incidence of cancer in the group. They were asked to complete questionnaires on their health and on how much time they were active and participating in activities such as walking,swimming and aerobics（有氧运动）and how much time they spent sitting watching television or reading.They completed the same questionnaires at two-year intervals between 1997 and 2009. Of the women,47% said walking was their only recreational activity.Those who walked for at least seven hours per week had a 14% lower risk of breast cancer compared to those who walked three or fewer hours per week. Dr. Alpa Patel, a senior epidemiologist at the American Cancer Society in Atlanta, Georgia, who led the study, said:”Given that more than 60% of women report some daily walking, promoting walking as a healthy leisure-time activity could be an effective strategy for increasing physical activity amongst post-menopausal women.We were pleased to find that without any other recreational activity, just walking one hour a day was associated with a lower risk of breast cancer in these women.””More strenuous（紧张的）and longer activities lowered the risk even more.” Baroness Delyth Morgan, chief executive of Breast Cancer Campaign,said:”This study adds further evidence that our lifestyle choices can play a part in influencing the risk of breast cancer and even small changes incorporate into our normal day-to-day activity can make a difference.” She added:”We know that the best weapon to overcoming breast cancer is the ability to stop it occurring in the first place. The challenge now is how we turn these findings into action and identify other sustainable lifestyle changes that will help us prevent breast cancer.”It can be inferred from Dr. Alpa Patel’s study that____.Awomen have fewer chances of physical activityBdaily walking could cut the chance of breast cancerCleisure-time activity is not associated with cancer riskDwalking is not recommended for women with breast cancer
单选题What does the word “that”stand for in the second paragraph?ABrain activity.BHer research findings.CThe fact that cell phone use may cause cancer.DHer research progress.
单选题Passage2Can electricity cause cancer？In a society that literally runs on electric power，the very idea seems preposterous.But for more than a decade，a growing band of scientists and journalists has pointed to studies that seem to link exposure to electromagnetic fields with increased risk of leukemia and other malignancies.The implications are unsettling，to say the least，since everyone comes into contact with such fields，which are generated by everything electrical，from power lines and antennas to personal computers and micro-wave ovens. Because evidence on the subject is inconclusive and often contradictory，it has been hard to decide whether concern about the health effects of electricity is legitimate-or the worst kind of paranoia.Now the alarmists have gained some qualified support from the U.S.Environmental Protection Agency. In the executive summary of a new scientific review，released in draft form late last week，the EPA has put forward what amounts to the most serious government warning to date.The agency tentatively concludes that scientific evidencesuggests a casual link”between extremely low-frequency electromagnetic fields-those having very long wave-lengths-and leukemia，lymphoma and brain cancer，While the report falls short of classifying ELF fields as probable carcinogens，it does identify the common 60-hertz magnetic field asa possible，but not proven，cause of cancer in humans.”The report is no reason to panic-or even to lost sleep.If there is a cancer risk，it is a small one.The evidence is still so controversial that the draft stirred a great deal of debate within the Administration，and the EPA released it over strong objections from the Pentagon and the White House.But now no one can deny that the issue must be taken seriously and that much more research is needed.At the heart of the debate is a simple and well-understood physical phenomenon: When an electric current passes through a wire, it generates an electromagnetic field that exerts forces on surrounding objects. For many years, scientists dismissed any suggestion that such forces might be harmful, primarily because they are so extraordinarily weak. The ELF magnetic field generated by a video terminal measures only a few milligauss, or about one-hundredth the strength of the earth' sown magnetic field, the electric fields surrounding a power line can be as high as 10 kilovolts permeter, but the corresponding field induced in human cells will be only about 1 millivolt per meter. This is far less than the electric fields that the cells themselves generate.How could such minuscule forces pose a health danger? The consensus used to be that they could not, and for decades, scientists concentrated on more powerful kinds of radiation, like X-rays, that pack sufficient wallop to knock electrons out of the molecules that make up the human body. Suchionizingradiations have been clearly linked to increased cancer risks and there are regulations to control emissions.But epidemiological studies, which find statistical associations between sets of data, do not prove cause and effect. Though there is a body of laboratory work showing that exposure to ELF fields can have biological effects on animal tissues,a mechanism by which those effects could lead to cancerous growths has never been found.The Pentagon is far from persuaded. In a blistering 33-page critique of the EPA report, Air Force scientists charge its authors with having biased the entire documenttoward proving a link. Our reviewers are convinced that there is no suggestion that(electromagnetic fields) present in the environment induce or promote cancer,the Air Force concludes.It is astonishing that the EPA would lend its imprimatur on this report.Then Pentagon's concern is understandable. There is hardly a unit of the modern military that does not depend on the heavy use of some kind of electronic equipment, from huge ground-based radar towers to the defense systems built into every warship and plane.What do you think ordinary citizens may do after reading the different arguments?AThey are indifferent.BThey are worried very much.CThey may exercise prudent avoidance.DThey are shocked.
单选题According to the passage, lung cancer _____.Ais the major cause of death between the ages of 35 and 55Bis most often caused by smokingCnever affects non-smokersDhas nothing to do with smoking
单选题Passage2Can electricity cause cancer？In a society that literally runs on electric power，the very idea seems preposterous.But for more than a decade，a growing band of scientists and journalists has pointed to studies that seem to link exposure to electromagnetic fields with increased risk of leukemia and other malignancies.The implications are unsettling，to say the least，since everyone comes into contact with such fields，which are generated by everything electrical，from power lines and antennas to personal computers and micro-wave ovens. Because evidence on the subject is inconclusive and often contradictory，it has been hard to decide whether concern about the health effects of electricity is legitimate-or the worst kind of paranoia.Now the alarmists have gained some qualified support from the U.S.Environmental Protection Agency. In the executive summary of a new scientific review，released in draft form late last week，the EPA has put forward what amounts to the most serious government warning to date.The agency tentatively concludes that scientific evidencesuggests a casual link”between extremely low-frequency electromagnetic fields-those having very long wave-lengths-and leukemia，lymphoma and brain cancer，While the report falls short of classifying ELF fields as probable carcinogens，it does identify the common 60-hertz magnetic field asa possible，but not proven，cause of cancer in humans.”The report is no reason to panic-or even to lost sleep.If there is a cancer risk，it is a small one.The evidence is still so controversial that the draft stirred a great deal of debate within the Administration，and the EPA released it over strong objections from the Pentagon and the White House.But now no one can deny that the issue must be taken seriously and that much more research is needed.At the heart of the debate is a simple and well-understood physical phenomenon: When an electric current passes through a wire, it generates an electromagnetic field that exerts forces on surrounding objects. For many years, scientists dismissed any suggestion that such forces might be harmful, primarily because they are so extraordinarily weak. The ELF magnetic field generated by a video terminal measures only a few milligauss, or about one-hundredth the strength of the earth' sown magnetic field, the electric fields surrounding a power line can be as high as 10 kilovolts permeter, but the corresponding field induced in human cells will be only about 1 millivolt per meter. This is far less than the electric fields that the cells themselves generate.How could such minuscule forces pose a health danger? The consensus used to be that they could not, and for decades, scientists concentrated on more powerful kinds of radiation, like X-rays, that pack sufficient wallop to knock electrons out of the molecules that make up the human body. Suchionizingradiations have been clearly linked to increased cancer risks and there are regulations to control emissions.But epidemiological studies, which find statistical associations between sets of data, do not prove cause and effect. Though there is a body of laboratory work showing that exposure to ELF fields can have biological effects on animal tissues,a mechanism by which those effects could lead to cancerous growths has never been found.The Pentagon is far from persuaded. In a blistering 33-page critique of the EPA report, Air Force scientists charge its authors with having biased the entire documenttoward proving a link. Our reviewers are convinced that there is no suggestion that(electromagnetic fields) present in the environment induce or promote cancer,the Air Force concludes.It is astonishing that the EPA would lend its imprimatur on this report.Then Pentagon's concern is understandable. There is hardly a unit of the modern military that does not depend on the heavy use of some kind of electronic equipment, from huge ground-based radar towers to the defense systems built into every warship and plane.The main idea of this passage is______.Astudies on the cause of cancerBcontroversial view-points in the cause of cancerCthe relationship between electricity and cancerDdifferent ideas about the effect of electricity on cancer
单选题阅读理解：请根据短文内容，为每题确定l个最佳选项。 A New Strategy to Overcome Breast Cancer。 Post-menopausal（绝经后）women who walk for an hour a day can cut their chance of breast cancer significantly,a study has suggested. The report, which followed 73,000 women for 17 years,found walking for at least seven hours a week lowered the risk of the disease.The American Cancer Society team said this was the first time reduced risk was specifically linked to walking. UK experts said it was more evidence that lifestyle influenced cancer risk. A recent poll for the charity Ramblers a quarter of adults walk for no more than an hour a week,but being active is known to reduce the risk of a number of cancers.This study, published in Cancer Epidemiology,BiomarkersPrevention,followed 73.615 women out of 97,785 aged 50-74 who had been recruited by the American Cancer Society between 1992 and 1993,so it could monitor the incidence of cancer in the group. They were asked to complete questionnaires on their health and on how much time they were active and participating in activities such as walking,swimming and aerobics（有氧运动）and how much time they spent sitting watching television or reading.They completed the same questionnaires at two-year intervals between 1997 and 2009. Of the women,47% said walking was their only recreational activity.Those who walked for at least seven hours per week had a 14% lower risk of breast cancer compared to those who walked three or fewer hours per week. Dr. Alpa Patel, a senior epidemiologist at the American Cancer Society in Atlanta, Georgia, who led the study, said:”Given that more than 60% of women report some daily walking, promoting walking as a healthy leisure-time activity could be an effective strategy for increasing physical activity amongst post-menopausal women.We were pleased to find that without any other recreational activity, just walking one hour a day was associated with a lower risk of breast cancer in these women.””More strenuous（紧张的）and longer activities lowered the risk even more.” Baroness Delyth Morgan, chief executive of Breast Cancer Campaign,said:”This study adds further evidence that our lifestyle choices can play a part in influencing the risk of breast cancer and even small changes incorporate into our normal day-to-day activity can make a difference.” She added:”We know that the best weapon to overcoming breast cancer is the ability to stop it occurring in the first place. The challenge now is how we turn these findings into action and identify other sustainable lifestyle changes that will help us prevent breast cancer.”All of the following factors relating to cancer risk were mentioned in the EXCEPT________.Abreathing exerciseBregular walkingCrecreational activityDlifestyle choices
单选题阅读理解：请根据短文内容，为每题确定l个最佳选项。 A New Strategy to Overcome Breast Cancer。 Post-menopausal（绝经后）women who walk for an hour a day can cut their chance of breast cancer significantly,a study has suggested. The report, which followed 73,000 women for 17 years,found walking for at least seven hours a week lowered the risk of the disease.The American Cancer Society team said this was the first time reduced risk was specifically linked to walking. UK experts said it was more evidence that lifestyle influenced cancer risk. A recent poll for the charity Ramblers a quarter of adults walk for no more than an hour a week,but being active is known to reduce the risk of a number of cancers.This study, published in Cancer Epidemiology,BiomarkersPrevention,followed 73.615 women out of 97,785 aged 50-74 who had been recruited by the American Cancer Society between 1992 and 1993,so it could monitor the incidence of cancer in the group. They were asked to complete questionnaires on their health and on how much time they were active and participating in activities such as walking,swimming and aerobics（有氧运动）and how much time they spent sitting watching television or reading.They completed the same questionnaires at two-year intervals between 1997 and 2009. Of the women,47% said walking was their only recreational activity.Those who walked for at least seven hours per week had a 14% lower risk of breast cancer compared to those who walked three or fewer hours per week. Dr. Alpa Patel, a senior epidemiologist at the American Cancer Society in Atlanta, Georgia, who led the study, said:”Given that more than 60% of women report some daily walking, promoting walking as a healthy leisure-time activity could be an effective strategy for increasing physical activity amongst post-menopausal women.We were pleased to find that without any other recreational activity, just walking one hour a day was associated with a lower risk of breast cancer in these women.””More strenuous（紧张的）and longer activities lowered the risk even more.” Baroness Delyth Morgan, chief executive of Breast Cancer Campaign,said:”This study adds further evidence that our lifestyle choices can play a part in influencing the risk of breast cancer and even small changes incorporate into our normal day-to-day activity can make a difference.” She added:”We know that the best weapon to overcoming breast cancer is the ability to stop it occurring in the first place. The challenge now is how we turn these findings into action and identify other sustainable lifestyle changes that will help us prevent breast cancer.”The word “sustainable” in the last paragraph is closest in meaning to_____.AaffordableBavailableCpersistentDcontinuable
单选题Passage2Can electricity cause cancer？In a society that literally runs on electric power，the very idea seems preposterous.But for more than a decade，a growing band of scientists and journalists has pointed to studies that seem to link exposure to electromagnetic fields with increased risk of leukemia and other malignancies.The implications are unsettling，to say the least，since everyone comes into contact with such fields，which are generated by everything electrical，from power lines and antennas to personal computers and micro-wave ovens. Because evidence on the subject is inconclusive and often contradictory，it has been hard to decide whether concern about the health effects of electricity is legitimate-or the worst kind of paranoia.Now the alarmists have gained some qualified support from the U.S.Environmental Protection Agency. In the executive summary of a new scientific review，released in draft form late last week，the EPA has put forward what amounts to the most serious government warning to date.The agency tentatively concludes that scientific evidencesuggests a casual link”between extremely low-frequency electromagnetic fields-those having very long wave-lengths-and leukemia，lymphoma and brain cancer，While the report falls short of classifying ELF fields as probable carcinogens，it does identify the common 60-hertz magnetic field asa possible，but not proven，cause of cancer in humans.”The report is no reason to panic-or even to lost sleep.If there is a cancer risk，it is a small one.The evidence is still so controversial that the draft stirred a great deal of debate within the Administration，and the EPA released it over strong objections from the Pentagon and the White House.But now no one can deny that the issue must be taken seriously and that much more research is needed.At the heart of the debate is a simple and well-understood physical phenomenon: When an electric current passes through a wire, it generates an electromagnetic field that exerts forces on surrounding objects. For many years, scientists dismissed any suggestion that such forces might be harmful, primarily because they are so extraordinarily weak. The ELF magnetic field generated by a video terminal measures only a few milligauss, or about one-hundredth the strength of the earth' sown magnetic field, the electric fields surrounding a power line can be as high as 10 kilovolts permeter, but the corresponding field induced in human cells will be only about 1 millivolt per meter. This is far less than the electric fields that the cells themselves generate.How could such minuscule forces pose a health danger? The consensus used to be that they could not, and for decades, scientists concentrated on more powerful kinds of radiation, like X-rays, that pack sufficient wallop to knock electrons out of the molecules that make up the human body. Suchionizingradiations have been clearly linked to increased cancer risks and there are regulations to control emissions.But epidemiological studies, which find statistical associations between sets of data, do not prove cause and effect. Though there is a body of laboratory work showing that exposure to ELF fields can have biological effects on animal tissues,a mechanism by which those effects could lead to cancerous growths has never been found.The Pentagon is far from persuaded. In a blistering 33-page critique of the EPA report, Air Force scientists charge its authors with having biased the entire documenttoward proving a link. Our reviewers are convinced that there is no suggestion that(electromagnetic fields) present in the environment induce or promote cancer,the Air Force concludes.It is astonishing that the EPA would lend its imprimatur on this report.Then Pentagon's concern is understandable. There is hardly a unit of the modern military that does not depend on the heavy use of some kind of electronic equipment, from huge ground-based radar towers to the defense systems built into every warship and plane.Why did the Pentagon and White House object to the release of the report?AIt may stir a great deal of debate among the Administration.BEvery unit of the modern military has depended on the heavy use of some kind of electronic equipment.CThe Pentagon's concern was understandable.DThey had different arguments.
单选题阅读理解：请根据短文内容，为每题确定l个最佳选项。 A New Strategy to Overcome Breast Cancer。 Post-menopausal（绝经后）women who walk for an hour a day can cut their chance of breast cancer significantly,a study has suggested. The report, which followed 73,000 women for 17 years,found walking for at least seven hours a week lowered the risk of the disease.The American Cancer Society team said this was the first time reduced risk was specifically linked to walking. UK experts said it was more evidence that lifestyle influenced cancer risk. A recent poll for the charity Ramblers a quarter of adults walk for no more than an hour a week,but being active is known to reduce the risk of a number of cancers.This study, published in Cancer Epidemiology,BiomarkersPrevention,followed 73.615 women out of 97,785 aged 50-74 who had been recruited by the American Cancer Society between 1992 and 1993,so it could monitor the incidence of cancer in the group. They were asked to complete questionnaires on their health and on how much time they were active and participating in activities such as walking,swimming and aerobics（有氧运动）and how much time they spent sitting watching television or reading.They completed the same questionnaires at two-year intervals between 1997 and 2009. Of the women,47% said walking was their only recreational activity.Those who walked for at least seven hours per week had a 14% lower risk of breast cancer compared to those who walked three or fewer hours per week. Dr. Alpa Patel, a senior epidemiologist at the American Cancer Society in Atlanta, Georgia, who led the study, said:”Given that more than 60% of women report some daily walking, promoting walking as a healthy leisure-time activity could be an effective strategy for increasing physical activity amongst post-menopausal women.We were pleased to find that without any other recreational activity, just walking one hour a day was associated with a lower risk of breast cancer in these women.””More strenuous（紧张的）and longer activities lowered the risk even more.” Baroness Delyth Morgan, chief executive of Breast Cancer Campaign,said:”This study adds further evidence that our lifestyle choices can play a part in influencing the risk of breast cancer and even small changes incorporate into our normal day-to-day activity can make a difference.” She added:”We know that the best weapon to overcoming breast cancer is the ability to stop it occurring in the first place. The challenge now is how we turn these findings into action and identify other sustainable lifestyle changes that will help us prevent breast cancer.”Dr. Alpa Patel was_____.Achief editor of Cancer Epidemiology.Bchair of the American Cancer Society.Chead of the survey study.Dchief executive of Breast Cancer Campaign.
单选题What did the report at San Antonio Breast Cancer Symposium illustrate?AFlaxseed is the most effective treatment for breast cancer.BBreast cancer is the main cause of death for women.CIt’s hard to cure breast cancer.DFlaxseed is a potential arsenal against breast cancer.