Shares of SurModics ( SRDX), a provider of drug delivery (coatings and implants) and surface modification (lubricity) technologies to the healthcare industry, fell to $10.82 Monday morning before pushing back up to $11.04. SurModics has an underperform rating from research firms Rodman & Renshaw and Barrington Research. China Sky One Medical ( CSKI), a Hong Kong-based manufacturer of over-the-counter and nutritional supplements, lost several points in early trading, falling to $6.33 per share. At midday the stock traded around $6.40, still down nearly 3% on the day. Shares of Insurance holding company 21st Century Holding ( TCHC) fell to $3.20 early Monday. At midday firm's shares were down nearly 4% on double their average trading volume. -- Written by Miriam Marcus Reimer in New York. >To contact the writer of this article, click here: Miriam Reimer. >To follow the writer on Twitter, go to http://twitter.com/miriamsmarket. >To submit a news tip, send an email to: email@example.com.