GLOBAL MARKETS-U.S. stocks dip, dollar higher after Fed statement

* U.S. stocks turn lower after Fed statement * Fed repeats to be "patient" in deciding when to raise rates * U.S. 30-year Treasury yield hits record low after Fed * Dollar still higher after Fed * European stocks end lower on persistent Greek worries (Updates with market reactions to Fed statement) By Caroline Valetkevitch NEW YORK, Jan 28 (Reuters) - Wall Street stocks edged lower on Wednesday while the dollar rose as the Federal Reserve said growth in the U.S. economy