US STOCKS-Wall St gains with upbeat earnings, more deal activity
* Merck quarterly profit tops estimate but revenue misses
* Twitter to report earnings after market close
* More U.S. companies beating earnings expectations
* Indexes up: Dow 0.6 pct, S&P 0.5 pct, Nasdaq 0.7 pct (Updates to afternoon, changes byline)
By Caroline Valetkevitch
NEW YORK, April 29 (Reuters) - U.S. stocks rose on Tuesday, helped by upbeat results from companies including Merck & Co and Sprint, as well as more deal activity on the healthcare front.
Merck & Co 's shares jumped 2.9 percent to $58.35, giving the S&P 500 its biggest lift, after it reported stronger-than-expected results.
Also, Britain's Reckitt Benckiser Group Plc confirmed talks to buy Merck's consumer health business, the latest asset up for grabs in a wave of recent pharmaceutical deals.
"We've gone through a fair chunk of earnings and market participants kind of get the story at this juncture. On balance, with expectations having been lowered, earnings beats are coming in around 70 percent and most of the forward-looking statements have generally been pretty decent," said Mark Luschini, chief investment strategist at Janney Montgomery Scott in Philadelphia, which manages about $63 billion in assets. Continuación...