1.   Amid all the optimism, however, researchers caution that the lifesaving effects of the protease drugs may not last.

2.   And researchers caution that much work still lies ahead.

3.   But other researchers cautioned against leaping to clinical conclusions based on this one study, and called for more and bigger trials.

4.   But researchers cautioned that these studies were the beginning of scientific investigations into alternative treatments, and not the final word.

5.   But researchers cautioned consumers to be aware that many herbal products did not contain what their labels stated and urged them to tell their doctors before taking the substances.

6.   But researchers cautioned that the findings were preliminary.

7.   But researchers caution that the effects of taking the drug over the course of a lifetime remain unknown.

8.   But researchers cautioned that people need to understand what they are getting into by having a scan.

9.   But the researchers cautioned that the LEAP program alone is not enough to raise graduation rates significantly.

10.   But the researchers cautioned that it does not necessarily follow that treatment reduces recidivism.