Buoyed by strong returns for shares of Microsoft and American Express, the Dow Jones Industrial Average is up Friday morning. Shares of Microsoft and American Express have contributed to the blue-chip gauge’s intraday rally, as the Dow is trading 57 points (0.2%) higher. Microsoft’s shares are up $4.37, or 1.9%, while those of American Express have gained $2.05, or 1.4%, combining for a roughly 42-point boost for the Dow. McDonald’s Visa and Dow are also contributing significantly to the gain. A $1 move in any of the benchmark’s 30 components equates to a 6.59-point swing.