1.   These vaccines have two serious disadvantages, however.

2.   And now, this vaccine could have a major impact on a part of the world where children suffer most.

3.   And, Moore added, he anticipated more such arguments to come as companies push to have vaccines tested that they hope might prevent HIV infections.

4.   But all six said the Russian vaccine had more serious side effects.

5.   But this time the vaccines have to work a lot harder.

6.   Dr. Michael D. Decker, a vice president of Aventis Pasteur, said the old vaccine still had a large quantity of virus particles.

7.   Earlier studies found that vaccines had no link to autism.

8.   Live attenuated vaccines have a long and illustrious history.

9.   Some AIDS researchers now believe that any vaccine will have to prevent infection, not just prevent the development of the disease after infection.

10.   Such a vaccine would have to generate killer T-cells, immune system warriors that recognize and destroy infected human cells.