One suggestion that works for me is to take the measure that is giving me grief and the measure preceding it. Play them as slowly as necessary to maintain constant tempo, and do this over and over for 5-10 minutes a day. Use a metranone and as you get better, speed it up about 5%. When you can consistantly do this at 120% of the tempo you want, you're ready to polish off the entire song.

While doing this, condinue to practice the rest of the song to commit it to memory.

As I said, this works for me.