p-Phenylenediamine, the allergen of the year? Why now? Granted, p-phenylenediamine (PPD) has been the leading permanent hair coloring agent or oxidative hair dye in most of the Western world since ...

A purified protein derivative (PPD) skin test is a test that determines if you have tuberculosis (TB). TB is a serious infection, usually of the lungs, caused by the bacteria Mycobacterium ...

The second diagnostic test option is known as a purified protein derivative (PPD) test, but it's commonly referred to as a TB skin test. "TB skin tests have been used in medicine for over a ...

That grew, eventually, into Pharmaceutical Product Development -- PPD-- a global contract research organization. With Eshelman as chairman and CEO, PPD grew to a payroll of more than 1,500 in ...

Background: Finding alternative hair dyes for individuals allergic to para-phenylenediamine (PPD) has been difficult. Newer permanent and demipermanent hair dyes that have replaced PPD with para ...