small matlab script needed to delete a bunch of rows in a mat file

I would need a small matlab script, which opens a .mat file that consists of several structural arrays, goes into 4 of those arrays and deletes a bunch of rows within a 2D matrix (contained within each of the 4 struc arrays). The script will need to be applied to 50 or so files. I don`t think this is a lot of work. Maybe a couple of hours for someone experienced with matlab.