There are advantages and disadvantages for both of the arguments.
1. 用动物做医疗实验是很重要的一项医药研究方法。 Experiment on animals is an essential medicines research approach.
2. 人类可以获得大量的[临床]数据，因为这种实验更有效。 Human could obtain a great quantity of clinical data as the experiment seems to be more effective.
3. 比如说，医学家经常用小白鼠做实验，研究治疗癌症药物的有效性。Remedy For example, medicines scientists always use mice to conduct experiments, researching medicine’s usefulness.
4. 如果让癌症病人尝试新药，风险很大，容易产生医疗事故。medical negligence If cancer patients are allowed to try new medicines, risking significantly and easily causing/leading to medical negligence. 5. 进一步说，用白鼠做实验，可以降低实验成本，因为它们繁殖快，饲养方便。Multiply Furthermore, testing on white mice may contribute to the decline of cost, as they multiply quickly as well as being raised conveniently.
6. 可见，用动物于医药研究可提高效率、降低风险和成本。 Generally, using animals to test medicines may significantly increase efficiency and reduce risks and costs. 转
1. 然而，因大量使用动物做药物实验，产生很多问题。 On the other hand, as lots of animals are used to test medicines, there are many problems.
In fact, it is easy to produce new viruses in the research lab.
3. 据报道，很多流行感冒的爆发很可能源于这种医学实验。 It is reported that breaking out of major flu probably originates/comes/stems from medicines researches.
4. 因此，环保主义者和动物保护者都一致反对这种实验，因为它的残酷。Defenders of Wildlife Therefore, both defenders of wildlife and environmentalists oppose/are against this kind of experiments because of its cruelty.
5. 他们认为， 人与动物都是大自然的重要组成部分，所以动物实验是违背自然规律的做法。 They think that human and animals are important components of nature, so animal experiments are against natural law.