2014年自考英語(yǔ)(二)閱讀輔導(dǎo):為科學(xué)而獻(xiàn)身

　　Sacrificed to Science?

　　Professor Colin Blakemore works at Oxford University Medical School doing research into eye problems and believes that animal research has given humans many benefits:The use of animals has been central to the development of anaesthetics, vaccines and treatments for diabetes, cancer, developmental disorders…most of the major medical advances have been based on a background of animal research and development.

　　There are those who think the tests are simply unnecessary. The International Association Against Painful Experiments on Animals is an organization that promotes the use of alternative methods of research which do not make animals suffer. Their spokesman Colin Smith says:

　　Animal research is irrelevant to our health and it can often produce misleading results. People and animals are different in their reactions to drugs and in the way their bodies work. We only have to look at some of the medical mistakes to see this is so.

　　But Professor Blackmore stresses:It would be completely irresponsible and unethical to use drugs on people that had not been thoroughly tested on animals. The famous example of thalidomide is a case for more animal testing, not less.

　　The birth defects that the drug produced were a result of inadequate testing. If thalidomide were invented today, it would never be released for human use because new tests on pregnant animals would reveal the dangers.

　　Another organization that is developing other methods of research is FRAME. This is the Fund for the Replacement of Animals in Medical Experiments. It recognises that many experiments still have to be done on animals and is aiming for Reduction, Refinement and Replacement of animals in experiments. In 1981, it established a research programme to improve and expand non-animal testing. Increasingly, new technology is making it easier for us to find alternative methods of testing.

　　Computer models can be used to simulate the way that cells work and to try to predict the toxicity of chemicals. Data from previous animal experiments is used to develop a computer model which will predict what will happen if you add a chemical with an unknown biological effect to a substance. The eventual aim of computer modeling is to reduce the number of animals used in experiments.

　　The Lethal Dose 50 test (LD50) may also be replaced. In the original test, all the animals in a test group are given a substance until half of them die. The test indicates toxicity. A method using a fixed amount, which gives the same eventual information but uses fewer animals and does not require that they die, may replace the LD50. Many other new techniques are now available that enable more research to be done in the test tube to see if chemicals produce harmful biological effects.

　　The number of animals used in laboratory tests has declined over the last 20 years. This is partly due to alternatives and partly to the fact that experiments are better disigned so fewer need to be used - healthier animals provide better experimental results. For example, it used to take 36 monkeys to test a sample of polio vaccine, now it takes only 22. Also, lack of money has reduced the number of animals used - they are expensive to buy and expensive to keep.

　　Birmingham University now has Britain's first department of Biomedical Ethics. Professor David Morton of the department is involved in animal research and is concerned with reducing animal suffering as much as possible. Animals spend 95% of their time in their cages and refinement also means making their lives better when not undergoing tests. This includes keeping them in more suitable cages, allowing social animals like dogs to live together and trying to reduce the boredom that these animals can experience.

　　In Professor Morton's laboratory, rabbits live together in large runs, filled with deep litter and boxes that they can hide in. The researchers have also refined some experiments. In the US, one experiment in nerve regeneration involves cutting a big nerve in a rat's leg, leaving its leg paralysed. In Morton's lab, the researcher cuts a small nerve in the foot. He can see if it can regrow and the rat can still run around its cage.

　　Even with these new developments in research, only a tiny proportion of all tests are done without using animals at some stage. The use of animals in experiments cannot stop immediately if medical research is to continue and consumer products are to be properly tested, and Professor Blakemore believes that sometimes there are no alternatives:

　　Wherever possible, for both ethical and scientific reasons, we do not use animals. But cells live in animals and we can only really see how they behave when they are inside animals. We cannot possibly reproduce in a test tube or a computer model all the complex reactions of the body to a drug or a disease. When it comes to research into heart disease and its effects on the body, or diseases of the brain for example, we do not have adequate substitutes for the use of animals.

　　As research techniques become more advanced, the number of animals used in experiments may decrease, but stopping testing on animals altogether is a long way away.

　　為科學(xué)而獻(xiàn)身

　　科林布萊克默教授在牛津大學(xué)醫(yī)學(xué)院工作，從事眼睛疾病的研究。他相信對(duì)動(dòng)物的研究已使人類獲益匪淺。

　　使用動(dòng)物對(duì)于麻醉學(xué)和疫苗的發(fā)展，對(duì)糖尿病、癌癥和紊亂的治療等極其重要。多數(shù)重要的醫(yī)學(xué)都是以動(dòng)物研究和開發(fā)的背景為基礎(chǔ)的。

　　有些人認(rèn)為這些實(shí)驗(yàn)毫無必要。國(guó)際反動(dòng)物痙實(shí)驗(yàn)協(xié)會(huì)是一個(gè)提倡使用不使動(dòng)物痙的替代方法的組織。他們的發(fā)言人科林史密斯說：對(duì)動(dòng)物的研究和我們的健康無關(guān)，它常常產(chǎn)生令人誤入歧途的結(jié)果。人和動(dòng)物對(duì)藥物的反應(yīng)及他們身體運(yùn)作的方式都不同。我們只要看一看醫(yī)療失誤就會(huì)明白。但布萊克默說：沒有認(rèn)真在動(dòng)物身上實(shí)驗(yàn)的藥物大人身上使用，是完全不負(fù)責(zé)和不合道理的。薩力多胺就是一個(gè)著名的例子。它證明需要更多的動(dòng)物實(shí)驗(yàn)而不是更少的動(dòng)物實(shí)驗(yàn)。這種藥物引起的先天性畸形是缺乏實(shí)驗(yàn)的結(jié)果。如果薩力多胺是現(xiàn)在發(fā)明的，它就不會(huì)被批準(zhǔn)為人類使用，因?yàn)樵谟性械膭?dòng)物身上實(shí)驗(yàn)會(huì)提示其危險(xiǎn)。

　　另一個(gè)開發(fā)其他研究辦法的組織是FRAME，"替代動(dòng)物醫(yī)學(xué)實(shí)驗(yàn)基金會(huì)"的簡(jiǎn)稱。它認(rèn)識(shí)到許多實(shí)驗(yàn)仍然不得不使用動(dòng)物，該基金會(huì)旨在減少使用動(dòng)物，改良使用動(dòng)物，甚至替代動(dòng)物。在1981年，它們?cè)O(shè)立了一個(gè)改進(jìn)和擴(kuò)大無動(dòng)物實(shí)驗(yàn)的研究項(xiàng)目。漸漸地，新科技使我們更易于找到進(jìn)行實(shí)驗(yàn)可供選擇的辦法。電腦模型可以用來模擬細(xì)胞的活動(dòng)方式和預(yù)測(cè)化學(xué)制品的毒性。以前的動(dòng)物數(shù)據(jù)用來開發(fā)一個(gè)電腦模型，它能預(yù)測(cè)如果一種物質(zhì)中加入某種未知生物作用的化學(xué)藥品會(huì)發(fā)生什么。電腦模型的最終目標(biāo)是減少用于實(shí)驗(yàn)的動(dòng)物數(shù)量。

　　致死計(jì)量50實(shí)驗(yàn)(LD50)也可以被代替。在過去的實(shí)驗(yàn)中，實(shí)驗(yàn)群中所有的動(dòng)物被喂給一種物質(zhì)，直到其中一半死亡。這個(gè)實(shí)驗(yàn)表明其毒性。一種用固定的數(shù)量可以得到相同的結(jié)論，但是使用較少動(dòng)物而且不使它們死亡的方法可能代替LD50?，F(xiàn)在已有許多其他的技術(shù)，可使更多的研究工作在試管中進(jìn)行，從而發(fā)現(xiàn)化學(xué)藥品是否產(chǎn)生有害的生物作用。

　　過去的20年里，實(shí)驗(yàn)室里實(shí)驗(yàn)中使用的動(dòng)物數(shù)量減少;其部分原因是由于可供選擇的方法多了，另外部分是由于實(shí)驗(yàn)設(shè)計(jì)得更好，因?yàn)槭褂酶】档膭?dòng)物能產(chǎn)生更好的實(shí)驗(yàn)結(jié)果，所以用的動(dòng)物減少了。例如，過去常用36只猴子來實(shí)驗(yàn)脊髓質(zhì)炎疫苗樣本，現(xiàn)在只用22只。缺少資料已使所使用的動(dòng)物數(shù)量減少了 ??購(gòu)買和使用動(dòng)物都很昂貴。

　　伯明翰大學(xué)現(xiàn)在設(shè)有英國(guó)首家生物醫(yī)學(xué)倫里學(xué)系。系里的大衛(wèi)莫頓教授從事動(dòng)物研究，并對(duì)盡可能地減少動(dòng)物的痙很關(guān)心。動(dòng)物們?cè)诨\子里度過了他們 95%的時(shí)間，改良也意味闃不進(jìn)行實(shí)驗(yàn)時(shí)使它和得更好些。這包括在更舒適的籠子里喂養(yǎng)它們，允許像狗那類喜歡合群的動(dòng)物生活在一起，盡量減少這些動(dòng)物可能經(jīng)歷的煩惱。

　　在莫頓教授的實(shí)驗(yàn)室里，大批兔子一起生活，到處是厚厚的干草和箱子供它們躲藏。者們還改進(jìn)了一些實(shí)驗(yàn)。在美國(guó)，神經(jīng)再生方面的發(fā)切斷鼠腳里的一條小神經(jīng)。他可以看到神經(jīng)是否可以再生，而老鼠仍在籠子里四處跑。

　　盡管這些研究有了新成果，所有的裕只有極少數(shù)在某一階段不使用動(dòng)物。

　　如果醫(yī)學(xué)實(shí)驗(yàn)研究還要繼續(xù)，消費(fèi)性門牌號(hào)學(xué)要嚴(yán)格地進(jìn)行檢驗(yàn)，這樣在實(shí)驗(yàn)中使用動(dòng)物就不會(huì)立即停止。布萊克莫教授相信有時(shí)是無可選擇的。

　　無論在何處，有可能的話，基于倫理和科學(xué)的原因，我們不應(yīng)使用動(dòng)物做實(shí)驗(yàn)。但是細(xì)胞生活在動(dòng)物體內(nèi)，只有當(dāng)細(xì)胞在動(dòng)物體內(nèi)時(shí)我們才能真正看清它們是如何活動(dòng)的。我們不可能在試管中或電腦模型里復(fù)制出身體對(duì)疾病或薌的所有復(fù)雜反應(yīng)。涉及到研究心臟病和它對(duì)身體的影響時(shí)，例如腦內(nèi)疾病，我們沒有代替使用動(dòng)物的合適的替代物。

　　隨著研究技術(shù)變得更先進(jìn)，實(shí)驗(yàn)中使用的動(dòng)物數(shù)量可能會(huì)減少，但完全停止在動(dòng)物身上實(shí)驗(yàn)還有很長(zhǎng)的路要走。

　　更多自考動(dòng)態(tài)請(qǐng)您持續(xù)關(guān)注環(huán)球網(wǎng)校自考頻道！

?2013年10月各省市自考成績(jī)查詢?nèi)肟趨R總

?2014年4月自考報(bào)名

更多信息請(qǐng)?jiān)L問：自學(xué)考試頻道    自學(xué)考試論壇