UPDATE 1-U.S.-based stock funds post $3.6 bln outflows over week - Lipper

(Adds analyst comment, additional flows, table) By Sam Forgione NEW YORK, April 17 (Reuters) - Investors in U.S.-based funds pulled $3.6 billion out of stock funds in the week ended April 16 on fears that a selloff in technology and biotech shares could signal a steeper drop in U.S. stocks, data from Thomson Reuters' Lipper service showed on Thursday. The outflows from stock funds marked the biggest since February. Outflows of $3.8 billion from stock exchange-traded funds accounted f