The healthcare stock is lagging the market this year.If a company's history and track record were good enough reasons to buy its shares, it'd be easy to make a case for investing in Abbott Laboratories (ABT 1.52%). Abbott is a longtime leader in the healthcare sector, and has generally delivered excellent returns to long-term shareholders.However, that's no guarantee of future returns. And detractors will point out that Abbott has encountered some headwinds lately, especially on the legal and regulatory fro ...