Merck Rises 1.52 Percent Before Bell  NEW YORK (Reuters) - Shares of drugmaker Merck   Co. Inc.  &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=MRK.N target=/stocks/quickinfo/fullquote"&gt;MRK.N&lt;/A&gt; traded 1.52 percent higher on volume of more than  61,000 shares in pre-market dealings on Friday, a day after the  stock plunged to an eight-year low after the company withdrew  its arthritis drug Vioxx.