11.   Although some studies have shown lipoxygenase inhibitors to be protective, more recent studies have not.

12.   Other studies have related antral carcinomas with lower social class, whereas tumours of the cardia have been associated with higher social class and with those of Caucasian origin.

13.   All the above suggest that income redistribution studies have to be treated with caution and any critical assumptions revealed by sensitivity analysis should be made clear.

14.   Mutation studies have until very recently only detected a few defects.

15.   Finally, since our main finding was the absence of a strong relation between age and mortality, it is appropriate to ask whether the study had sufficient power.

16.   Although the new research does not examine the problems of specific cultural institutions in specific cities, the studies have clear implications for New York.

17.   Asked about the findings, Dr. Grigory Kizelshteyn, an associate professor of anesthesiology at New York Medical College, says the study has limitations.

18.   Because the study had uncovered windows, it took place, as did others later, in the windowless hallway adjacent to the study, the report said.

19.   Both companies also claim to be achieving results comparable to standard procedures, although definitive studies have yet to be done.

20.   Both studies have numerous critics.