As was mentioned in previous posts (here and here), whole blood can go into a test tube and then be separated into layers with cells in the bottom portion of the tube and plasma above. It turns out that although some lab tests require whole blood or plasma, others need only blood serum (pronouced how rare steaks can be cooked – just sear ’em).
Serum is the result when clotting proteins are removed from plasma.
When a clot activator is added to the test tube in which blood is drawn, the sample can be centrifuged, leaving only serum at the top of the tube. This serum can then be poured off and tested.
Still trying to break information down into bite-sized chunks.
∞ itis 
As always, you’re a wealth of information. Having taken Anatomy and Physiology as well as Microbiology in college, I was familiar with some of this information. However yesterday when I got my new prescription for Arava and learned that it is unclear how it works but has something to do with white blood cells, your recent posts took on a whole new level of importance. With everything going on in your life, thank you for continuing to take the time to share your knowledge and insights with others.
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Waiting for more “blood” posts and wondering how you’re doing! Wren too!
Chelsea
Swamped! I am swamped! Haven’t been online much. Thanks for asking. I hope to get a post up in the next couple days.
Hoping the swamped means you are feeling good enough to be swamped in the first place! Have to let us know how the meds and shoulder are doing. And how is daughter doing?
I’ve been doing ROM/strengthening exercises for my shoulder, so it’s doing better. Not perfect, but better. Every time I drop my pred dose, the shoulder starts aching again!
The cimzia seems to have finally kicked it. I’m supposed to take it every 14 days, and it lasts 11, so it’s pretty obvious that/when the med is working. Also, my mtx dose increased and that’s helping, too.
Daughter has okay days and bad days. No good days. Her rheum’s first available appt isn’t until September, so PCP doubled her mobic to see if that would help. It seems to, but yesterday she came and asked if she had to wait a full six hours between doses of Tylenol, or if four hours would be okay since it wears off then. 😦