Adam Sarhan Reuters Quote: GLOBAL MARKETS-Yellen helps offset Ukraine worry; S&P 500 hits record
* S&P 500 closes at record high * Russian ruble hits 5-year low vs dollar * Euro bounces off 2-week low * U.S. Treasuries’ yields at two-week low Thu Feb 27, 2014 4:42pm EST By Chuck Mikolajczak NEW YORK, Feb 27 (Reuters) – Stocks on world markets mostly advanced on Thursday, while the S&P 500 closed at a record high, as comments from U.S….