Submit an article to a national medical journal after being preliminarily accepted for publication at another?

It is highly unethical to submit the same article to another journal after it has been accepted elsewhere. If you pulled the article from the state journal after it was accepted and one of the many reviewers saw it published elsewhere (e.g., in a national journal) you would probably be rebuked professionally and the editors from both journals could decide a retraction was warranted. That's NOT the way you want to see your name in print. Moreover, what happens if your article is rejected by the second journal? Now you have significantly delayed publications. You have to realize that expert reviewers in a specific field know each other, often sit on the same journal review boards and look down on what you are considering. At this early stage of your career (or any time) I would strongly advise against it.