These guys have a pretty comprehensive forum on various military stuff. The medical stuff has some good info.
My advice, though? Just lurk and use it as a resource. Don't sign up and don't dare ask a question. The guys running the site are grade A douchebags. They have an allergy to sharing their knowledge and they'd rather preen about how awesome they are instead of actually answering a question.
So, good resource, douchebag members. Avoid them, but take what you can from the site.
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