Is there any way to make the images not italicized?

By default the images rendered appear to be italicized, like this:
http://latex.codecogs.com/gif.latex?Dutycycle=\frac{\frac{PDCx}{2}-DT}{PTPER+1}
 
I discovered the \textup syntax, but it's really a pain to wrap it around all the letters and
numbers, like this:
 
http://latex.codecogs.com/gif.latex?\textup{Dutycycle=}\frac{\frac{\textup{PDCx}}{\textup{2}}\textup{-DT}}{\textup{PTPER+1}}
 
Is there any way to make the text not italicized by default?

Thanks!

Just wrap your entire equation in mathrm, i.e

\mathrm{\sqrt{a^2+b^2}}

to give you

Original look like this:

Thanks, works like a charm!