【正文】 ield against harmful substances.　　The study focused on changes in cells that line blood vessels and on whether such changes could weaken the functioning of the bloodbrain barrier, which prevents potentially harmful substances from entering the brain from the bloodstream. Leszczynski said.　　The study found that a protein called hsp27 linked to the functioning of the bloodbrain barrier showed increased activity due to irradiation and pointed to a possibility that such activity could make the shield more permeable(能透過的), he said.　　Increased protein activity might cause ceils to shrinknot the blood |vessels hut the cells themselvesand then tiny gaps could appear between those cells through which some molecules could pass. he said.　　Leszezynski declined to speculate on what kind of health risks that could pose, but said a French study indicated that headache, fatigue and sleep disorders could result.　　These are not lifethreatening problems but can cause a lot of disfort, he said, adding that a Swedish group had also suggested a possible link with Alzheimer39。s new findings? ________　　A Radiation has contributed to the disease.　　B Putting a lot of people from rural area in a large towns increases the risk of childhood leukaemia.　　C Population mixing is the most important reason for leukaemia cluster.　　D Childhood leukaemia is caused by an unusual infection.　　33 According to the passage, which of the following is true? ________　　A Most people believe childhood leukaemia is due to environmental factors.　　B Population mixing best explains the cause of childhood leukaemia.　　C Radiation has nothing to do with childhood leukaemia.　　D Children born in a large town are at higher risk of leukaemia.　　34 Cancer Research Campaign is most possibly a ________.　　A medical journal　　B research institute　　C private pany　　D governmental agency　　35 This passage is mainly about ________.　　A the cluster of leukaemia eases around the Sellafield nuclear reprocessing part　　B the kind of infection that causes childhood leukaemia　　C the causes of childhood leukaemia　　D a new finding by British scientists 來源第二篇 Mobile Phone and Diseases　　A study by scientists in Finland has found that mobile phone radiation can cause changes in human cells that might affect the brain, the leader of the research team said.　　But Darius Leszczynski, who headed the 2year study and will present findings next week at a conference in Quebec(魁北克), said more research was needed to determine the seriousness of the changes and their impact on the brain or the body.　　The study at Finland39。請仔細(xì)閱讀短文并根據(jù)短文回答其后面的問題，從4個選項中選擇1個最佳答案涂在答題卡相應(yīng)的位置上。s character, we use a different, more mature style of thinkingand the most plex areas of our cortex, which allow us to be humane.　　23 Paragraph 2 ________　　24 Paragraph 3 ________　　25 Paragraph 4 ________　　26 Paragraph 5 ________　　A Ways of Departure from Immature and Simplistic Impressions　　B Comment on First Impression　　C Illustration of First Impression　　D Comparing Ining Sensory Information Against Memories　　E Threatening Aspect of First Impressions　　F Differences Among Jocks, Geeks and Freaks　　27 Sensory information is one that is perceived through ________.　　28 You interpret ________ by paring it against the memories already stored in your brain.　　29 The way we stereotype people is a less mature form of thinking, which is similar to ________.　　30 We can use our more mature style of thinking thanks to ________.　　A a stranger39。m intrigued. Or your brain may perceive a new face but familiar clothes, ethnicity, gestures—like your other friends。s eyes, ears, nose, or mouth are placed in relation to each other make you see him or her as different. In fact, your brain continuously processes information—the sights and sounds of your world. These ining signals are pared against a host of memories stored in the brain areas called the cortex system to determine what these new signals mean.　　3 If you see someone you know and like at school, your brain says familiar and safe. If you see someone new, it says, new—potentially threatening. Then your brain starts to match features of this stranger with other known memories. The height, weight, dress, ethnicity, gestures, and tone of voice are all matched up. The more unfamiliar the characteristies, the more your brain may say, This is new. 1 don39。請將答案涂在答題卡相應(yīng)的位置上。s peopie residing in citied balloons from 31 percent in l995 to a projected 50 percent in 2005. And there is also the pressure of dollars to purchase land lying above groundwater sources and to keep it in a natural state, in order to protect aquifers (蓄水層) from contamination. In the developing countries, where urban population growth is surpassing sewage systems, the problem of untreated human waste is extremely serious.　　Alongside the problems of public groundwater sources is the increased consumption of privately bottled water, most of which is named spring wa