Not really. It's a particle system and, by definition, they're random.
However, the SEED parameter can be used to reproduce the effects precisely. That is, if you set up a CC Bubbles effect on your system and want me to duplicate it, all you have to do is give me all of the settings and your seed number and the bubbles will be precisely the same on both of our machines, asumign everything else is the same.
So, you might be able to keyframe the seed parameter to bring you back to the start of your animation but I doubt it will work as you hope.
Thanks David I guess I'll use Trapcode. I was waiting for a response before I bought it. Also I saw a tutorial on looping particles but how can you seamless loop moving or animated particles like random bubbles or spots.
if you are considering trying this with particular, you might try cc particle world. it will do a lot of similar particle effects as particular, but it comes with ae. and you can definitely do the looping particle trick with particle world the same way as particular.
the reason that you can do the loop trick with a these particle systems is that when you start and stop the emitter/producer the particles that were already produced will stay on the screen for their lifespan, allowing you to duplicate the particle system and back-time one of them so the particles matchup. with bubbles, when you set the number of bubble to 0, they all disappear, so you can't do the same trick.
about the best you could do with bubbles would be to create several layers of them (like foreground, middle ground, background bubbles) then use cross-fades to generate the loops, but stagger the cross-fades so they are less apparent.