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Passage 1 It's one of our common beliefs that mice are afraid of cats. Scientists have long known that even if a mouse has never seen a cat before, it is still able to detect chemical signals released from it and run away in fear. This has always been thought to be something that is into a mouse's brain. But now Wendy Ingram, a graduate student at the University of California, Berkeley, has challenged this common sense. She has found a way to "cure" mice of their inborn fear of cats by infecting them with a parasite, reported the science journal Nature. The parasite, called Toxoplasma gondii, might sound unfamiliar to you, but the shocking fact is that up to one-third of people around the world are infected by it. This parasite can cause different diseases among humans, especially pregnant women-it is linked to blindness and the death of unborn babies. However, the parasite's effects on mice are unique. Ingram and her team measured how mice reacted to a cat's urine (尿) before and after it was infected by the parasite. They noted that normal mice stayed far away from the urine while mice that were infected with the parasite walked freely around the test area. But that's not all. The parasite was found to be more powerful than originally thought-even after researchers cured the mice of the infection. They no longer reacted with fear to a cat's smell, which could indicate that the infection has caused a permanent change in mice's brains. Why does a parasite change a mouse's brain instead of making it sick like it does to humans? The answer lies in evolution. "It's exciting scary to know how a parasite can manipulate a mouse's brain this way," Ingram said. But she also finds it inspiring. "Typically if you have a bacterial infection, you go to a doctor and take antibiotics and the infection is cleared and you expect all the symptoms to also go away." She said, but this study has proven that wrong. "This may have huge implications for infectious disease medicine."The author's attitude towards the experiment is ______.
关于小肠肿瘤的临床特点,不正确的是()
下列哪项肿瘤是恶性瘤( )
什么是阅读教学?阅读与阅读教学有什么区别?
撮合业务项下直接融资“多对一”模式,资金方人数不得超过()人。
反渗析
在生产技术准备过程中,用于产品设计、组织生产,增强对市场多品种、中小批量产品需求适应性,提高效益的有效方法和途径的是
下列涉税专业服务业务中,代理记账机构可以从事的是()。
有一名枕骨大孔疝病人,其诊断要点是( )。
为准确代表每日从尿液中排出物质的量,多数化学定量分析须收集的尿液为( )。
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