91.   But some scientific studies now say that for contaminants like ground-level ozone, known as smog, any exposure may be harmful.

92.   But the Ginsburg-Gabel study says otherwise.

93.   But the evidence is inconclusive, the study says, about whether immunization increases the risk of asthma.

94.   But the Sedway Kotin study said there are stark differences between Phoenix and Denver.

95.   But some scientific studies now say that for contaminants like ground-level ozone, known as smog, any amount may be harmful.

96.   But the study also says that the Adirondacks ecosystem is not improving, suggesting that further reductions in sulfur dioxide will be necessary.

97.   But such a reduction would translate into cost savings, the study said.

98.   But the Wharton study says computers will not necessarily hurt the pay of the lower-skilled workers or automate them out of employment.

99.   But the Harbour study said buying from suppliers is cheaper in many situations.

100.   But the new study says such policies would do little to help those who are not now attending college.