and some of the more recently introduced agents = ?

and some of the more recently introduced agents = and (towards resistance to ) some of the more recently introduced agents?

Plus, what does "introduced" mean? Available?

Context:

However, even in these more careful countries, resistance can still be an issue, often after the importation of 4 multiresistant bacterial strains or the overuse of 5 antibiotics in farmed animals.There are many alarming examples of increasing resistance in bacteria that commonly infect patients in the community and health-care settings. Among gram-positive bacteria, meticillin-resistant Staphylococcus aureus 6 (MRSA) has attracted media and public policy attention. Some MRSA strains have shown a disturbing creep towards resistance to glycopeptides and some of the more recently introduced agents, such as daptomycin and 7 oxazolidinones. Community-acquired MRSA strains have spread globally, and are also now becoming increasingly common in healthcare settings. Glycopeptide-resistant enterococci are a concern in many countries, and new 8 mechanisms of resistance continue to develop.The resistance problem is even worse for gram-negative bacteria, both in community and hospital settings.