Space travel is definitely bad for astronauts’ bones, reducing their bone densit
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Space travel is definitely bad for astronauts’ bones, reducing their bone density(密度) after only a month of weightlessness, according to French research published on Friday. Laurence Vico and his fellow workers at St Etienne University called for more research into the effects of microgravity, after their study of 15 astronauts from the Russian MIR station showed bone loss continued throughout space flights. “Bone loss was especially striking in four astronauts, ” the scientists reported in the Lancet Medical Journal. They measured the bone mineral density (BMD) of bones in the forearm(前臂) and lower leg of the astronauts who had spent one to six months in space. The BMD loss was significant in the tibia(胫骨) of the lower leg, a weight-bearing bone, but barely changed in the radius(桡骨) of the forearm. “Our results indicate the need to investigate not only different bones, but also different areas of the same bone since not all sites of the skeleton (骨架) are similarly affected by space conditions, ” they added. Without gravity the body isn’t bearing any weight so there is no need for calcium (钙) which makes bones strong, and it becomes empty into the bloodstream. The research team suggested in future scientists should try to determine if the loss of bone density was only on weight-bearing bones on longer flights, also the possible recovery after returning to Earth. 小题1:French scientists did their research on Russian astronauts, because _______.A.they only cared for the Russian astronauts | B.they were not interested in their own astronauts | C.the Russian government invited them to do their research | D.the Russian astronauts worked in space for a long time | 小题2:Scientists have found that _______.A.the BMD loss may cause serious illness to astronauts | B.the BMD loss may cause some change in astronauts’ bodies | C.astronauts shouldn’t care about the BMD loss | D.astronauts should take some calcium before space travel | 小题3:What cause the BMD loss to astronauts, according to this passage?A.The food they eat in space. | B.The drinks they take in space. | C.The temperature in space. | D.The gravity in space. | 小题4:In the third paragraph, the word “striking” means ______.A.unusual | B.simple | C.weak | D.slow |
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答案
小题1:D 小题2:B 小题3:D 小题4:A |
解析
本文介绍了法国对太空宇航员长期在太空飞行,会使骨里的密度减少而对骨不利的研究。 小题1:细节题。根据文章第4段的定语从句who had spent one to six months in space可推知此题答案为D。 小题2:细节题。根据文章第5段第1句The BMD loss was significant in the tibia(胫骨) of the lower leg, a weight-bearing bone可推知此题答案为B。 小题3:细节题。根据文章第6段Without gravity…所引起的结果,可推知此题答案为D。 小题4:词义猜测题。上文提到对十五人进行研究表明在整个航行过程中骨损在继续,下文再说especially striking,可知是“特别明显”的事,因此选A。 |
举一反三
Want a glance of the future of health care? Take a look at the way the various networks of people about patient care are being connected to one another, and how this new connectivity is being exploited to deliver medicine to the patient —no matter where he or she may be. Online doctors offering advice based on normal symptoms(症状) are the most obvious example. Increasingly, however, remote diagnosis(远程诊断) will be based on real physiological data(生理数据) from the actual patient. A group from the University of Kentucky has shown that by using personal data assistance plus a mobile phone, it is perfectly practical to send a patient’s important signs over the telephone. With this kind of equipment, the cry asking whether there was a doctor in the house could well be a thing of the past. Other medical technology groups are working on applying telemedicine to rural(countryside) care. And at least one team wants to use telemedicine as a tool for disaster need—especially after earthquakes. On the whole, the trend is towards providing global access to medical data and experts’ opinions. But there is one problem. Bandwidth(宽带) is the limiting factor for sending complex(复杂的) medical pictures around the world — CT photos being one of the biggest bandwidth users. Communication satellites may be able to deal with the short-term needs during disasters such as earthquakes or wars. But medicine is looking towards both the second-generation Internet and third-generation mobile phones for the future of remote medical service. Doctors have met to discuss computer-based tools for medical diagnosis, training and telemedicine. With the falling price of broadband communications, the new technologies should start a new time when telemedicine and the sharing of medical information, experts’ opinions and diagnosis are common. 小题1: The writer chiefly talks about _______.A.the use of telemedicine | B.the on-lined doctors | C.medical care and treatment | D.communication improvement | 小题2:The basis of remote diagnosis will be _______.A.personal data assistance | B.some words of a patient | C.real physiological information | D.medical pictures from the Internet | 小题3:Which of the following statements is true according to the text?A.Patients don’t need doctors in hospitals any more. | B.It is impossible to send a patient’s signs over the telephone. | C.Many teams use telemedicine dealing with disasters now. | D.Broadband communications will become cheaper in the future. | 小题4:The “problem” in the fourth paragraph refers to the fact that _______.A.bandwidth isn’t big enough to send complex medical pictures | B.the second-generation of Internet has not become popular yet | C.communication satellites can only deal with short-term needs | D.there is not enough equipment for spreading the medical care |
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A new study has found no evidence that sunscreen, commonly used to reduce the risk of skin cancer, actually increase the risk. Researchers from the University of Iowa based their findings on a review of 18 earlier studies that looked at the association between sunscreen use and melanoma (黑素瘤). They said that they found flaws in studies that had reported associations between sunscreen use and higher risk of melanoma Most health experts believe that by protecting the skin from the harmful effects of the sun, sunscreen helps prevent skin cancer, which is increasing in incidence (发生率) faster than any other cancer in the United States. But questions has been raised about sunscreen and whether it may has opposite effect, perhaps by allowing people to remain exposed to the sun longer without burning. The researchers said that among the problems with some earlier studies is that they often failed to take into account that those people most at risk for skin cancer--- people with fair skin and freckles (雀斑), for example--- are more likely to use sunscreen. As a result, it may appear that sunscreen users get cancer more often. The studies, which generally relied on volunteers to recall their sunscreen use, were also unable to prove how well the products had been applied, said the new study. 小题1:72. The underlined word “flaws” in the 2nd paragraph most probably means ______.A.evidence | B.facts | C.faults | D.failures | 小题2:73. People with fair skin and freckles .A.seldom use sunscreen | B.are more in danger of skin cancer | C.can be free from the harm of the sun | D.often expose themselves to the sun | 小题3:74. We can learn from the passage that ______.A.sunscreen users get skin cancer more often | B.the volunteers have proved the effect of sunscreen | C.the new study was based on the experiences of volunteers | D.the number of skin cancer patients is increasing in America | 小题4:75. Which of the following can be the title for this passage?A.Sunscreen to Prevent Skin Cancer | B.Sunscreen to Increase Skin Cancer | C.Skin Cancer Caused by Sunscreen | D.Skin Cancer Caused by Freckles |
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D Seeing a volcano erupt (喷发) is a wonderful experience, and you can really feel the beat by climbing to the summit(山顶) of Pacaya for a close-up view. There are guided tours every day up this highly active volcano from Antigua. Giving travelers a chance to see Mother Nature at her most powerful. Pacaya is an easy drive from Antigua, a beautiful city with many colorful houses along its old streets that are turned into art-works during its Holy Week festival. No matter when you come to Antigua, you won’t miss the Pacaya-tour companies. But climbing Pacaya is no easy job: it is 2560 metres high, and reaching the summit takes two to three hours of seemingly one-step-forward and two-step-back movements. As you climb, you hear the dull sounds of eruptions high above. Steaming. Hot remains from recent eruptions begin to line the path as you near the active summit; the McKenney Cone(火山锥). Just as though you were going to walk over to the edge of the cone, the road turns to the left and up to the relative safety of the old, inactive summit. Many tours are timed so that you arrive at the cone of the volcano is plenty of time for sunset and the full contrast between the erupting red lava(熔岩) and the darkening sky. On a good day the view from the summit is extremely exciting. The active mouth boils, sending red lava over its sides, and once in a while shoots hot streams up to 100 metres into the air. There is a strong bad smell in the air even if you take care to be upwind of the cone. As evening turns deeper into the night. the burning lava quietly falls down tae side of the volcano. For you, too, it is time to get down . 小题1: What is the main purpose of this passage?A.To attract tourists to Pacaya. | B.To describe the beauty of Pacaya. | C.To introduce guided tours to Pacaya. | D.To explain the power of nature at Pacaya. | 小题2:Antigua is a city .A.where people can enjoy cultural festivals | B.where the daring Pacaya tour starts | C.that gives a close-up view of Paraya | D.that is famous for its tour companies | 小题3:Climbing to the McKenney Cone, people will .A.walk directly to the active summit | B.hear the continuous loud noise from above | C.make greater efforts than to other summits | D.see a path lined with remains of earlier eruptions | 小题4: Many tours are timed for people to .A.get down the mountain in time when night falls | B.avoid the smell from the upwind direction of the cone | C.enjoy the fantastic eruption against the darkening sky | D.appreciate the scenery of the 2560-metre-high mountain |
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Centuries ago, man discovered that removing moisture from food helps to store it, and that the easiest way to do this is to expose the food to sun and wind. All foods including water — cabbage and other leaf vegetables contains as much as 93% water, potatoes and other root vegetables 80%, lean (瘦的) meat 75% and fish, anything from 80% to 60%, depending on how fatty it is. If this water is removed, the activity of the bacteria which cause food to go bad is controlled. Nowadays most foods are dried mechanically. The conventional method of such dehydration (脱水) is to put food in chambers (室) through which hot air is blown at temperature of about ll0"C at entry to about 43"C at exit. This is the usual method for drying such things as vegetables, minced meat, and fish. Liquids such as milk, coffee, tea, soups and eggs may be dried by pouring them over a heated steel cylinder (圆筒), then put them into a chamber through which a current of hot air passes. In the first process, the dried material comes off the roller (滚筒) as a thin film which is then broken up into small, though still relatively flakes (薄片). In the second process it falls to the bottom of the chamber as small powder. Where recognizable pieces of meat and vegetables are required, as in soup, the ingredients (成分) are dried separately and then mixed. Dried foods take up less room and weigh less than the same food packed in cans or frozen, and they do not need to be stored in special conditions. For these reasons they are invaluable to the climbers, explorers and soldiers in battle, who have little storage space. They are also popular with housewives because it takes so little time to cook them. 小题1:It can be inferred from the passage that ________.A.the rattier fish contain as much water as the lean one | B.the rattier the fish is, the more water it may contain | C.a fatty fish holds less water than a lean one | D.the water content of fish has nothing to do with the content of their fat | 小题2: The underlined word "conventional" in Paragraph 3 can most probably be replaced by _________.A.particular | B.scientific | C.usual | D.special | 小题3:Which of the following statements is NOT true about drying food?A.The removal of water in food helps prevent it from going rotten. | B.The open-air method of drying food has been known for hundreds of years. | C.In the course of dehydration, the temperature of hot current coming from entry to exit is gradually going up. | D.The process of drying liquids is much more complex than that of drying solid food. | 小题4:The last paragraph mainly talks about __________.A.the reason why housewives like dried food | B.the general convenience of dried food | C.the methods of storing food | D.the advantages of dried, canned and frozen food |
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Gene technology to benefit people Among all the fast growing science and technology, the research of human genes, or biological engineering as people call it, is drawing more and more attention now. Sometimes it is a hot topic discussed by people. The greatest thing that gene technology can do is to cure serious diseases that doctors at present can almost do nothing with, such as cancer and heart disease. Every year, millions of people are murdered by these two killers. And to date, doctors have not found an effective way to cure them. But if the gene technology is applied, not only these two diseases can be cured completely, bringing happiness and more living days to the patients, but also the great amount of money people spend on curing their diseases can be saved, therefore it benefits the economy as well. In addition, human life span(寿命) can be prolonged. Gene technology can help people to give birth to more healthy and clever children. Some families, with the English imperial family being a good example, have hereditary(遗传的) diseases. This means their children will for sure have the family disease, which is a great trouble for these families. In the past, doctors could do nothing about hereditary diseases. But gene technology can solve this problem perfectly. The scientist just need to find the wrong gene and correct it, and a healthy child will be born. Some people are worrying that the gene research can be used to manufacture human beings in large quantities. In the past few years, scientists have succeeded in cloning a sheep, therefore these people predict that human babies would soon be cloned. But I believe cloned babies will not come out in large quantities, for most couples in the world can have babies in very normal way. Of course, the governments must take care to control gene technology. 小题1:What does "these two killers" in the second paragraph refer to? A.gene technology and another treatment of the two diseases. | B.The two murderers who killed the cloned baby | C.The two diseases of cancer and heart disease | D.Hereditary diseases and cancer | 小题2: What"s the main idea of the third paragraph?A.How gene technology can be applied in the field of treating hereditary diseases. | B.Gene technology can be used to clone human babies. | C.Gene technology can help people to give birth of a baby. | D.Gene technology can help the English imperial family out | 小题3:In what way gene technology can help to treat hereditary diseases?A.Using gene technology, people with hereditary diseases can have more living days. | B.Using gene technology, scientist finds the wrong gene and corrects it. | C.Using gene technology, human babies can be cloned. | D.Doctors can cure cancer and heart disease with the help of gene technology. | 小题4:What is the main purpose of writing this passage?A.Expressing the writer"s idea that gene technology will benefit people | B.Telling people the advantages of gene technology | C.Telling the readers that gene technology will not benefit people | D.Explaining that gene technology will also do harm to the humanity |
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