Investors breathed a sigh of relief today, focusing on the positive aspects of positive economic data rather than lingering on the potential impact that the favorable news might have on the Federal Reserve's decision about future interest-rate policy. Responding optimistically to news from China that the central bank there is handling its liquidity crunch with measured responses, as well as good economic data on the U.S. housing front, the Dow Jones Industrials (DJINDICES:^DJI) took the opportunity to climb just over 100 points, making it the 10th triple-digit move in the past 11 trading days. Broader benchmarks moved upward even more aggressively, with the S&P 500 rising almost 1%.

Interestingly, several of the stocks from the health-care and technology industries that performed the best in yesterday's Dow decline were laggards this time around. On the health-care front, UnitedHealth (NYSE:UNH) fell 1.4%, giving up most of its gains from yesterday. Despite a recent dividend increase, and indications that the company is well-prepared to handle the full implementation of Obamacare, UnitedHealth is suffering from all the uncertainties investors have about the impact of Obamacare and other health-care policies on the health-insurance industry. With shares at a reasonable valuation of just 12 times trailing earnings, UnitedHealth offers some margin of safety against the potential for adverse news in the near future.

Merck (NYSE:MRK) also declined, with a 0.4% drop, even though the company won a legal battle against potential generic competition. As Fool contributor Dan Carroll noted earlier today, Merck got an injunction to protect its Januvia and Janumet diabetes drugs from an Indian company seeking to make generic versions of the drug. With the drugs having assumed the role of Merck's blockbusters, any threat has potentially large implications for the pharmaceutical company, which has already faced plenty of damage from past patent expirations.

On the tech front, both Microsoft (NASDAQ:MSFT) and Cisco Systems (NASDAQ:CSCO) fell modestly. Yet, both had interesting news, with Microsoft choosing to form a single venture-capital enterprise called Microsoft Ventures to foster promising start-up companies. The move takes what had been separate programs that had slightly different focus areas, and combines them into a single entity, arguably helping to make the venture's efforts more efficient. Meanwhile, Cisco traded higher earlier in the day, as an appeals court ruled in its favor in a case alleging that it infringed the patents of Commil USA, a small Texas company. The jury verdict had awarded Commil USA $63.8 million, but the appeals court will now send the case back to trial for proper handling of the legal issues involved.

A single day's losses aren't any big deal for any of these four companies. With advances for the stock market becoming harder to come by, though, it's important for stocks to take maximum advantage of any strong days they get.

Fool contributor Dan Caplinger has no position in any stocks mentioned. You can follow him on Twitter @DanCaplinger. The Motley Fool recommends Cisco Systems and UnitedHealth Group. The Motley Fool owns shares of Microsoft. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.