It sounds like the article may be a scanned image rather than actual text?
If so, you can try exporting/saving (depending on your version of Acrobat) to a Word document then extract the image out of that or you can export all of the images (in Acrobat X it's Tools>Document Processing>Export all images) from the PDF then use Insert>Image in Word.
If it's still blurry, you have an image with a low resolution. Not much you can do with that other than make it smaller in Word.