干细胞是一种尚未充分分化的未成熟的细胞,它具有再生各种细胞、器官的潜能,医学家们正尝

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问题:

干细胞是一种尚未充分分化的未成熟的细胞,它具有再生各种细胞、器官的潜能,医学家们正尝试利用干细胞治疗一些顽疾,用骨髓移植法有效治疗白血病便是成功的例证。下列说法中不正确的是()

A.利用干细胞治疗某些顽疾,是因为干细胞具有再生各种组织、器官的潜能

B.干细胞携带本物种全部遗传信息

C.用骨髓移植法治疗白血病的优点之一是不发生排斥(异)反应

D.异体骨髓移植成功后,康复者的血型有可能发生改变

考点:高中生物胚胎工程胚胎工程题库
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The fridge is considered a necessity. It has been so since the 1960s when packaged food first appeared with the label: "store in the refrigerator. "
In my fridgeless fifties childhood, I was fed well and healthy. The milkman came daily, the grocer, the butcher, the baker, and the ice cream man delivered two or three times a week. The Sunday meat would last until Wednesday and surplus bread and milk became all kinds of cakes. Nothing was wasted, and we were never troubled by rotten food. Thirty years on, food deliveries have ceased, fresh vegetables are almost unobtainable in the country.
The invention of the fridge contributed comparatively little to the art of food preservation. A vast way of well tried techniques already existed—natural cooling, drying, smoking, salting, sugaring, bottling…
What refrigeration did promote was marketing—marketing hardware and electricity, marketing soft drinks, marketing dead bodies of animals around the globe in search of a good price.
Consequently, most of the world’s fridges are to be found, not in the tropics where they might prove useful, but in the wealthy countries with mild temperatures where they are climatically almost unnecessary. Every winter, millions of fridges hum away continuously, and at vast expense, busily maintaining an artificially cooled space inside an artificially heated house—while outside, nature provides the desired temperature free of charge.
The fridge’s effect upon the environment has been evident, while its contribution to human happiness has been insignificant. If you don’t believe me, try it yourself, invest in a food cabinet and turn off your fridge next winter. You may miss the hamburgers, but at least you’ll get rid of that terrible hum.

Why does the author say that nothing was wasted before the invention of fridges

A.People would not buy more food than was necessary.
B.Food was delivered to people two or three times a week.
C.Food was sold fresh and did not get rotten easily.
D.People had effective ways to preserve their food.

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自强是一种美好的道德品质。以下属于自强表现的是:

A.刚愎自用,固执己见

B.好高骛远,一意孤行

C.唯我独尊,孤芳自赏

D.志存高远,执着追求

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办公自动化的任务主要有()。

A.信息支持

B.电子数据处理

C.信息管理

D.决策支持

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中国心境障碍的患病率与西方国家相比()

A.比西方国家高

B.与西方国家一样高

C.比西方国家低

D.与西方国家一样低

E.以上都不对

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安全技术交底由()负责实施,实行逐级安全技术交底制度

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