问题 问答题 论述题

试述肾上腺皮质激素的临床应用。

答案

参考答案:1、替代或补充疗法:用于治疗肾上腺皮质功能不全症、肾上腺次全切除术后等。

2、严重感染:原则上限于严重感染并伴有明显毒血症者如中毒性菌痢、中毒性肺炎等,应用糖皮质激素在于减轻炎症反应、缓解中毒症状、预防中毒性休克、使病人渡过危险期。但可降低机体防御功能,且无抗菌作用,故应用时必须与足量有效抗生素合用,以免导致感染扩散。

3、抑制排斥反应:通过免疫抑制作用,可应用于如脏器移植手术后或异体皮肤的排斥反应。

4、抗休克:糖皮质激素可用于各种休克,有助于病人渡过危险期。

5、血液病:可用于急性淋巴细胞性白血病、再生障碍性贫血、血小板减少症等。

选择题
单项选择题

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。

The main purpose of the last paragraph is to()

A. argue in favor of one side on a particularly controversial topic of cloning

B. display both sides’ arguments on another contentious issue in cloning

C. redirect the readers’ attention to the previously raised issue of ethics in cloning

D. provide further relevant information to the evaluation of cloning as a preservation technique