Analysts' Upgrades, Downgrades: Semtech

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TheStreet.com Ratings upgraded Amsurg(AMSG Quote) to "buy." The company develops and operates ambulatory-surgery centers in partnership with U.S. physician-practice groups.

The numbers: Fiscal first-quarter revenue rose 12% to $163 million as net income climbed 7.8% to $13 million and earnings per share ascended 8.1% to 40 cents, extending a growth streak to nine quarters. The cash balance is ample with $31 million of reserves. The debt-to-equity ratio is low at 0.6. The net margin is wide at 7.7% but has shed 30 basis points since last year's first quarter.

The stock: Amsurg is down 10% in 2009, trading at a price-to-earnings ratio of about 13. The company has a market capitalization of $670 million.

TheStreet.com Ratings initiated coverage of China Bio Energy(CBEH Quote) at "hold." The company explores for, produces and distributes biodiesel, heavy oil and finished oil products. Roth Capital just initiated coverage as well, slapping a $9 price target and "buy" rating on the stock.

The numbers: Fiscal first-quarter revenue surged 65% as net income climbed 54% to $7.2 million and earnings per share jumped 40% to 21 cents. The company has $36 million of cash, a high quick ratio of 10, and just $2.2 million of debt. The net margin is big at 12%.

The stock: Shares of China Bio Energy are down 5% since being listed on Nasdaq. The company has a market capitalization of just $146 million.

TheStreet.com Ratings upgraded Edison International(EIX Quote) to "buy." Edison is a holding company for public utility California Edison and several non-utility energy companies.