Hey there
The tax man up here has a little spot called professional fees/dues etc (line 212 on the form)- I always put in my licensing fee, any courses I took,my union dues, and any other small things(ie uniforms) that are involved with nursing. I don't think that there is a limit of how much you can put in there for uniforms etc because its all a part of your job, as long as your shelling your hard earned money for that you should be able to count it towards your taxes.
Hope this helps!