The topic of cloning has been a politicall

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The topic of cloning has been a politically and ethically controversial one since its very beginning. While the moral and philosophical aspects of the issues are entirely up to the interpretation of the individual, the application of cloning technology can be studied objectively. Many in the scientific community advocate the use of cloning for the preservation and support of endangered species of animals, which aside from cloning, have no other practical hope for avoiding extinction.

The goal of the use of cloning to avoid extinction is the reintroduction of new genes into the gene pool of species with few survivors, ensuring the maintenance and expansion of genetic diversity. Likely candidates for this technique are species known to have very few surviving members, such as the African Bongo Antelope, the Sumatran Tiger, and the Chinese Giant Panda. In the case of Giant Panda, some artificial techniques for creating offspring have already been performed, perhaps paving the way for cloning as the next step in the process.

With the estimated population of only about 1000 Giant Pandas left in the world, the urgency of the situation has led to desperate measures. One panda was born through the technique of artificial insemination in the San Diego Zoo in the United States. "Hua Mei" was born in 1999 after her parents, Hsing-Hsing and Ling-Ling, had trouble conceiving naturally.

The plan to increase the Giant Panda population through the use of cloning involves the use of a species related to the Giant Panda, the American Black Bear. Egg cells will be removed from female black bears and then fertilized with Panda cells such as those from Ling-Ling or Hsing-Hsing. The fertilized embryo will then re-implanted into the black bear, where it will grow and mature, until a new panda is delivered from the black bear host.

Critics of cloning technology argue that the emphasis on cloning as a method by which to preserve species will draw funding away from other methods, such as habitat preservation and conservation. Proponents of cloning counter that many countries in which many endangered species exist are too poor to protect and maintain the species’ habitats anyway, making cloning technology the only practical way to ensure that those species survive to future generations. The issue is still hotly debated, as both sides weigh the benefits that could be achieved against the risks and ethical concerns that constantly accompany any argument on the issue. (402 words)

Notes: ethically 道德上。gene pool 基因库。insemination n.受精。fertilize 使受精。embryo 胚胎。proponent支持者,拥护者。weigh A against B权衡A和B的利弊。

It can be inferred from the information given in the text that the best candidate for cloning would be()

A. Giant Pandas

B. an endangered species with many living related species

C. the species in which previous techniques of artificial reproduction have been successfully applied

D. those for which cloning is the only feasible method by which to reproduce the species

考点:普通考研西医综合西医综合
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患者,男性,30岁。左侧腹部撞击伤后2周。体检:全腹压痛,左上腹可以触及一包块,边缘不清、触痛明确。经非手术治疗后症状缓解。1小时前突然再次出现腹部持续性疼痛并向左肩部放射。体检:血压75/52mmHg,脉搏每分钟110次,腹平坦,左上腹压痛,移动性浊音阳性,肠鸣音消失。

脾损伤最常见的病理类型是().

A.脾包膜裂伤

B.脾包膜下血肿

C.脾中央型破裂

D.脾实质和包膜同时破裂

E.脾静脉断裂

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企业资产管理比率指标主要有( )。

A.净资产周转率

B.总资产周转率

C.流动资产周转率

D.预付账款周转率

E.存货周转率

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甲状腺危象的治疗主要是()

A.口服大剂量的丙硫氧嘧啶,症状缓解后给予一般剂量

B.口服或静脉滴注无机碘溶液

C.给予普萘洛尔或利血平

D.肾上腺皮质激素的应用

E.支持及对症处理

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1948年三大战役中首先展开的是()

A.辽沈战役

B.淮海战役

C.平津战役

D.渡江战役

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DNA 复制(DNA replication)

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