Sickle-cell disease is a painful disorder of the red blood cells that in the united states affects mostly african americans. to investigate whether the drug hydroxyurea can reduce the pain associated with sickle-cell disease, a study by the nih gave the drug to 150 sickle-cell sufferers and placebo to another 150. neither doctors nor patients were told who received the drug. the number of episodes of pain reported by each subject was recorded. this is an example of a(n):

David, an aspiring baseball player, was struck on the left side of his face with a fastball pitch. he was not wearing a safety helmet. his zygomatic arch was crushed, as well as parts of the temporal bone. following the accident and reconstructive surgery, he noted that his left lower eyelid was still drooping and the corner of his mouth sagged. what nerve damage did he sustain?

A70 year-old female has a drooping left eyelid obstructing her vision and has consented to having the blepharoptosis repaired. a skin marking pencil was used to outline the external proposed skin incision on the left upper eyelid. the lower edge of the incision was placed in the prominent eyelid crease. the skin was excised to the levator aponeurosis. an attenuated area of levator aponeurosis was dehisced from the lower strip. three 6-0 silk sutures were then placed in mattress fashion, attaching this attenuated tissue superiorly to the intact tissue inferiorly. this provided moderate elevation of the eyelid. what cptâ® code is reported?

Bloodborn pathogens are infectious microorganisms carried by what?