Google Inc's disappointing first-quarter results left Wall Street unfazed about the internet giant's ability to come to grips with the shift to the fast-growing mobile advertising market.

Google shares were down about 3 percent in early trading on Thursday, and at least 12 brokerages cut their target price on the stock. But most analysts kept a "buy" rating or equivalent on the company's shares.

"Despite an expectations-miss quarter, Google remains one of the best-positioned stocks for many of the secular growth drivers in the Internet space," RBC Capital analyst Mark Mahaney, who kept his "outperform" rating on the stock, said in a note to clients.

Of the 46 analysts covering Google, 35 have a "buy" or equivalent rating on the stock. Nobody has a "sell".

Google, Facebook Inc and Twitter Inc are revamping their products and advertising business to try to take advantage of a global shift to mobile phones and tablets.

For investors in Google, accustomed to the company enjoying one of the highest ad margins in the business, mobile ads have translated to a steep drop in ad rates.

Advertising rates on mobile phones are typically cheaper than traditional online ads because of their smaller screens. But mobile advertising continues to make up a bigger slice of the revenue of Internet companies.

Google company reported a 26 percent increase in paid clicks volumes but the average cost-per-click declined 9 percent.

"Google remains a core internet holding and we reiterate our "overweight" rating," Morgan Stanley said in a note titled "Keep calm and search on".

Analysts highlighted core revenue growth from Google websites and YouTube, higher contribution from rest-of-world revenue, strong sales of digital apps and content in Google's Play Store and Chromecast TV dongles.

Many also expect Google's Enhanced Campaigns advertisement program and other ad products to improve monetization from mobile and noted management's view that location and other data would help mobile pricing over time.

"We continue to recommend GOOGL due to the strength of the core search business, continued product innovation, and improving monetization, which should allow GOOGL to take a growing share of the desktop and mobile online ad markets," Susquehanna analyst Brian Nowak said.

Piper Jaffray analyst Gene Munster also remained upbeat.

"We continue to view Google as the best long term large cap story in our coverage space given the company's focus on innovation," he said.

However, Goldman Sachs, which has a "neutral" rating on Google's shares, said it expected the stock to remain range-bound in the near-term as the market waits for mobile cost-per-click rates to improve.

Google shares were trading at $545.22 shortly after the opening on the Nasdaq after closing at $563.90 on Wednesday.