Staples Profit Up, to Enter China Market  NEW YORK (Reuters) - Staples Inc. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=SPLS.O target=/stocks/quickinfo/fullquote"&gt;SPLS.O&lt;/A&gt;, the top U.S.  office products retailer, on Tuesday reported a 39 percent jump  in quarterly profit, raised its full-year forecast and said it  plans to enter the fast-growing Chinese market, sending its  shares higher.