"Before each training session, rats from one group were exposed for one hour to pulsed microwaves, radiation similar to that emitted by cellular telephones."
So they weren't exposed to actual cell phones. It wouldn't surprise me at all if the level of radiation the rats were receiving was tens or hundreds of times greater than what you would get with normal cell phone use. As far as I'm concerned this study has no relation to cell phones.
Until someone reputable publishes a study that definitively proves that cell phone use is harmful, I see no reason to believe any of this.