Fluid exchange between capillaries and the interstitial fluid. takes place between the blood and interstitial fluid across the thin endothelial walls of the capillaries. blood pressure drives fluid out of the capillaries, blood proteins pull fluid back in the capillaries by osmotic pressure. Difference in osmotic pressure and blood pressure drives fluids out of capillaries at the arteriole end and into capillaries at the venule end.
Premarket approval (PMA) is the FDA process of scientific and regulatory review to evaluate the safety and effectiveness of Class III medical devices.remarket approval (PMA) is the FDA process of scientific and regulatory review to evaluate the safety and effectiveness of Class III medical devices.
Two regulatory frameworks support the FDAâs review of prescription drugs. First, FDA reviews the safety and effectiveness of new drugs that manufacturers wish to market in the United States; this process is called premarket approval or preapproval review.Second, once a drug has passed that threshold and is FDA-approved, FDA acts through its postmarket or post-approval regulatory procedures.he following CRS reports provide overview information on FDAâs processes for approval and regulation of drugs: â¢ CRS Report R41983, How FDA Approves Drugs and Regulates Their Safety and Effectiveness, by Susan Thaul.