Melissa asks about silver stains for Alzheimers disease.
For many years we used the Bodian method (Bodian, D., A"A new method for staining nerve fibers and nerve endings in mounted paraffin sections" Anat. Rec.65:89 - 97. 1936) It worked just fine. We purchased our Protargol from Chroma and had no problems. It required a long incubation, but the results we thought, were worth the results.
Then a new neuropathologist arrived and he insisted on the Bielschowsky. I have always found that stain hard to do. Lately we have been trying out a new method where the final incubation is performed at 4 degrees C. It stops the reaction getting out of hand. You may want to try it. The reference is Litchfield. Suzanne.,Nagy. Zsuazanna. "New Temperature modification makes the Bielschowsky silver stain reproducible" Acta Neuropathol. 101: 17-21. 2001
Hope this helps.

Mike Titford
USA Pathology
Mobile AL 36617 USA