Sure! And it's pretty easy.
1) Click on USER CP
2) In the box called "New Subscribed Threads", click the link named "VIEW ALL SUBSCRIBED THREADS"
3) Beside the label "Notification", there's a selection box. If you hover your mouse over it, you'll see that it's called "Check/Uncheck All". Click this box to check *all* of your subscribed threads.
4) Now scroll to the bottom of the screen, and look for the drop-down box labeled "Selected Threads". In the drop down box, you'll have several options, including the ability to delete the selected subscriptions (unsubscribe), or to stay subscribed but with no email notification.
Does that work for you?