Editor's Note: Any reference to TheStreet Ratings and its underlying recommendation does not reflect the opinion of TheStreet, Inc. or any of its contributors including Jim Cramer or Stephanie Link. All three major indices are trading up today with the Dow Jones Industrial Average ( ^DJI) trading up 49 points (0.3%) at 16,147 as of Friday, Nov. 29, 2013, 11:45 AM ET. The NYSE advances/declines ratio sits at 1,869 issues advancing vs. 987 declining with 109 unchanged. The Health Services industry currently sits up 0.3% versus the S&P 500, which is up 0.3%. On the negative front, top decliners within the industry include Boston Scientific ( BSX), down 0.7%, Grifols ( GRFS), down 0.6% and Quest Diagnostics ( DGX), down 0.5%. TheStreet would like to highlight 3 stocks pushing the industry lower today: 3. Thoratec Corporation ( THOR) is one of the companies pushing the Health Services industry lower today. As of noon trading, Thoratec Corporation is down $2.67 (-6.3%) to $39.45 on heavy volume. Thus far, 603,144 shares of Thoratec Corporation exchanged hands as compared to its average daily volume of 565,900 shares. The stock has ranged in price between $39.23-$40.42 after having opened the day at $39.80 as compared to the previous trading day's close of $42.12. Thoratec Corporation engages in the development, manufacture, and marketing of proprietary medical devices used for circulatory support. Thoratec Corporation has a market cap of $2.4 billion and is part of the health care sector. The company has a P/E ratio of 53.3, above the S&P 500 P/E ratio of 17.7. Shares are up 12.3% year to date as of the close of trading on Wednesday. Currently there are 10 analysts that rate Thoratec Corporation a buy, no analysts rate it a sell, and 3 rate it a hold. TheStreet Ratings rates Thoratec Corporation as a buy. The company's strengths can be seen in multiple areas, such as its revenue growth, largely solid financial position with reasonable debt levels by most measures, good cash flow from operations, expanding profit margins and increase in stock price during the past year. We feel these strengths outweigh the fact that the company has had somewhat disappointing return on equity. Get the full Thoratec Corporation Ratings Report now. STOCKS TO BUY: TheStreet Quant Ratings has identified a handful of stocks that can potentially TRIPLE in the next 12-months. Learn more.