纳指低开0.45%，微软跌超2%

Group 1 - The core viewpoint of the article indicates that U.S. stock indices opened lower, reflecting increased market risk aversion due to specific corporate news [1] - The Dow Jones index fell by 0.05%, the S&P 500 index decreased by 0.21%, and the Nasdaq index dropped by 0.45% [1] - Microsoft reported a reduction in sales quotas for its artificial intelligence software, which led to a 2.77% decline in its stock price, negatively impacting technology stocks and overall market performance [1]