first filter.
I meant more like the "wizards have to have book learning spells" kind of wizard than actual magic. Mostly the actual body does most of the healing. In our world, we don't have instant-heal spells. Barry heals fast because superpowers, but the rest of us when we get hit, we just have to heal from it the slow way. But she uses science and knowledge to figure out how to help it along and such.
The needles - for stitching wounds back up? You guys do that, right? But also to inject things that she makes via science that help the body do different things. Fight off disease or be immune to it or take blood out to test for different properties. Think our version of alchemy and healing potions that she uses needles to inject if she needs to.
I might be confusing more than helping. Come hang out at the lab and I'll show you some books and video to do a better job than I'm doing, if you want.