U.S. stock

The Dow Jones industrial average rose 147 points, or 0.9 percent, to 16,646 as of 9:35 a.m. Eastern time Wednesday.

The Standard & Poor's 500 index climbed 17 points, or 0.9 percent, to 1,986. The Nasdaq composite rose 46 points, or 1 percent, to 4,857.

Japan's market jumped the most in almost seven years as investors hoped for more stimulus measures. Markets in China and Europe also rose sharply.

KEEPING SCORE: Dow Jones industrial average and Standard & Poor's 500 index futures were down 0.3 percent as of 8:50 a.m. Eastern time. In Europe, Germany's DAX shed 0.3 percent and France's CAC-40 lost 0.3 percent. Britain's FTSE 100 was flat.

In China, the Shanghai stock index plunged 8.5 percent Monday, its worst fall since 2007, despite government efforts to calm the market.

Teva Pharmaceutical Industries of Israel jumped 8 percent after saying it would buy Allergan's generic drug business. Allergan jumped 7.5 percent.

The Dow Jones industrial average lost 133 points, or 0.8 percent, to 17,435 as of 9:35 a.m. Eastern time.