题干

根据下列资料,分析回答问题:

自2013年4月以来,我国多地相继出现H7N9禽流感病毒感染人事件,许多科研人员为了有效控制疫情,作了如下的实验:

实验1

取活的H7N9禽流感病毒注射在一只健康鸡(A)的体内,不久,A鸡死亡.

实验2

  取灭活的H7N9禽流感病毒注射在另一只健康鸡(B)的体内,经过几周后,

再取活H7N9禽流感病毒注射在它的体内,结果B鸡存活下来.

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同类题1

革命或改革往往是某种旧制度阻碍社会经济的发展而发生的,懂得改变是一种智慧。
请阅读下列材料,回答问题。
材料一:如果总的看一看1861年俄国国家全部结构的改变,那就必然会承认,这种改变是封建君主制转变的道路上的一步。不仅从经济观点来看是正确的,而且从政治观点来看也是正确的。
--------列宁《关于纪念日》
材料二:大约在150年前,一个位于太平洋西岸的岛国,在西方殖民者坚船利炮的胁迫下遭遇生存危机。出人意料的是,它将此作为自己弃旧图新······这个岛国依然是世界第二大经济强国。
------------电视片《大国崛起》解说词
材料三:北方人看不惯南方人,南方人不服北方人。······当前南北之间的矛盾不是别的,而是两种社会制度之间的斗争。这个斗争之所以爆发,是因为这两种制度不能再在北美大陆上和平共处了。
-----------马克思《美国内战》
(1)依据材料一结合所学知识指出1861年使俄国发生改变的历史事件是什么? 列宁为什么说它是正确的?
(2)材料二中的“岛国”指的是哪个国家? 19世纪60年代末,该国抓住机遇“弃旧图新”,是以什么重大事件为起点, 这一重大事件有什么积极作用?
(3)材料三中的“斗争”指什么? 这场斗争是谁领导的? 他在“斗争”中颁布了哪两个重要法律?
(4)材料一、二、三反映的历史事件对各国产生了什么共同影响?
(5)上述三国的崛起之路给我国社会主义现代化建设带来了哪些成功经验?

同类题4

阅读下面短文,从下面每小题的A、B、C、D四个选项中选出最佳选项,并在答题卡将相应的字母编号涂黑。    

    Students at a primary school in Fuzhou, Hast China's Fujian Province were required to clean the school toilets to help them develop good habits. But some parents are strongly against the idea. They can't see the advantages of students doing such chores (杂亊). They think that the school should provide students with a proper education, not the chance to be school cleaners.

    In fact, parents, schools and society play an equally (同等地)important role in developing the character of students. It is good for schools to give students such tasks, because few of the students will do them at home. Their parents want them to do homework only.

    In recent years, some parents will make mountains out of molehills when students are asked to do some chores in schools. Some complain about the teachers if their kids get hurt in schools; some even challenge the schools' teaching methods and management. As a result, many primary schools, especially those in big cities, do not let students join in outdoor activities during breaks, fearing that they might get hurt. This is bad for the development of students' best qualities.

    What the primary school in Fuzhou is doing is worth praising. Doing chores can put a sense of responsibility into students' minds and teach them the spirit of rules as well as teamwork. Also, it can make students' in﹣school experiences more meaningful.