NEW YORK ( TheStreet) -TheStreet Ratings' stock model upgraded Cephalon ( CEPH) to 'Buy' from 'Hold'. Net income at this $4.8 billion market cap, biopharmaceutical company grew 5.1% to $89 million in second quarter over the prior second quarter.

TheStreet Ratings released rating changes on eight additional U.S. common stocks for September 24, 2010. In total, just one stock was downgraded and eight stocks have been upgraded by our stock model.

Second quarter revenue at Cephalon grew by 32.7% to $727 million over the same quarter last year. Learn more about Cephalon: Company Profile, Income Statement, Balance Sheet, Stock Ratios, Analyst Ratings.

In another upgrade, shares of RBC Bearings Inc ( ROLL) have moved to 'Buy' from 'Hold'. Fiscal first quarter net income increased by 79% to $9.1 million while revenue advanced by 29% to $82 million from the year earlier quarter. Learn more about RBC Bearings: Company Profile, Income Statement, Balance Sheet, Stock Ratios, Analyst Ratings.

-- Reported by Kevin Baker in Jupiter, Fla.

For additional Investment Research check out our Ratings Research Center.

Kevin Baker became the senior financial analyst for TheStreet Ratings upon the August 2006 acquisition of Weiss Ratings by TheStreet.com, covering mutual funds. He joined the Weiss Group in 1997 as a banking and brokerage analyst. In 1999, he created the Weiss Group's first ratings to gauge the level of risk in U.S. equities. Baker received a B.S. degree in management from Rensselaer Polytechnic Institute and an M.B.A. with a finance specialization from Nova Southeastern University.

More from Investing

The Stock Market Has Every Reason to See a Fresh Rally

The Stock Market Has Every Reason to See a Fresh Rally

3 Simple Tips on Investing From TheStreet's Jim Cramer

3 Simple Tips on Investing From TheStreet's Jim Cramer

Tesla's Supercharger Network Is Booming -- Here's Why That's a Concern

Tesla's Supercharger Network Is Booming -- Here's Why That's a Concern

After PayPal Buys iZettle, Pay-Tech Firms Could Process These Deals

After PayPal Buys iZettle, Pay-Tech Firms Could Process These Deals

Attention 60 Minutes: Google Isn't the Only Big-Tech Monopoly

Attention 60 Minutes: Google Isn't the Only Big-Tech Monopoly