All three major indices were in the green Thursday afternoon as the second quarter earnings season kicks into high gear. 

Not all stocks were helping push the market higher, however, with biopharmaceutical company AstraZeneca plc (AZN) - Get Report falling 14.67% to $28.96 after trials for its lung cancer drug Mystic failed. "Despite the outcome of the initial readout, we must be patient as the Mystic trial continues as planned to evaluate overall survival," CEO Pascal Soriot said.

Twitter Inc. (TWTR) - Get Report was also on the wrong side of trading following its earnings release Thursday. Twitter shares were down 13% to $17.06 in afternoon trading after it reported having 328 million monthly active users while the market was expecting the company to report 328.8 million active users.

Verizon Communications Inc. (VZ) - Get Report shares were rising 7% to $47.44 after the telecom company reported surprisingly strong second quarter subscriber gains. Verizon said it added 614,000 net post-paid accounts, including 368,000 phone accounts, in the second quarter. Earnings of 96 cents per share matched expectations, while sales of $30.5 billion topped expectations of $29.81 billion.

Comcast Corp. (CMCSA) - Get Report shares were up nearly 2% on heavier than usual volume following the company's strong second quarter beat. Revenue for the company's NBCUniversal division increased 17%, thanks in part to strong performances from its movie division, even as the company's cable subscription segment continued to bleed customers. 

People like to celebrate success and news that Amazon.com Inc. (AMZN) - Get Report CEO Jeff Bezos just overtook Bill Gates as the world's wealthiest man with a net worth of $90 billion is helping push the stock up 0.5% on heavy trading volume. 

Southwest Airlines Co. (LUV) - Get Report shares were experiencing turbulence after the company guided toward lower-than-expected current quarter unit revenue. Southwest now expects current quarter revenue per available seat mile to grow 1%, about half of what it previously expected. 

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