US STOCKS-Wall St little changed as healthcare stocks limit gains
* GM, Boeing rise after strong results
* Valeant sinks after Citron report
* VMware, Yahoo down on poor results
* Dow up 0.26 pct, S&P up 0.06 pct, Nasdaq down 0.04 pct (Updates prices, adds details)
By Abhiram Nandakumar
Oct 21 (Reuters) - U.S. stocks were little changed on Wednesday as healthcare stocks resumed their slide for a second day, offsetting gains by General Motors and technology stocks.
The S&P 500's healthcare sector declined 1.08 percent, while the Nasdaq biotech index fell 1.5 percent.
Valeant Pharma's U.S.-listed shares sank 20.8 percent to $116.23, and were halted, after short-seller Citron Research released a critical report on the company.
Health insurers Aetna, Humana, Anthem and Cigna all fell about 4 percent after Democratic presidential candidate Hillary Clinton said she had "serious concerns" about the mergers the companies were proposing. Continuación...