it's a tough case, i believe that people would rationalize that a human life is worth more than an animal life, and though i do not exactly like the idea of animal testing/research, i do think that provided the research is progressing the technology or understanding of ailments to humans, that it can be benificial and that it is something that should be allowed.
i also feel that there can be ethical standards that can be implemented upon animal research that can make it more of an acceptable practice, but if it came down to it i think that if a paticular experiament was going to take place and cause harm/ pain ect. to animals yet the outcome would be that it would allow researchers to discover a cure for AIDs or something that there is a trade off that can be made, usualy in favor of human advancement > animal rights