1 A ligand is any molecule that binds to a specific site on a protein or other molecule. In this case, the estrogen hormone 17-beta-estradiol is the ligand, and the estrogen receptor is the protein.  Binding turns on, or activates, a hormone receptor.
A femoral nerve block is a type of regional anesthesia in which the femoral nerve, located in the groin area, is deadened to allow surgery in the leg or knee area.
Femoral popliteal bypass surgery is used to treat blocked femoral artery. The femoral artery is the largest artery in the thigh. It supplies oxygen-rich blood to the leg. Blockage is due to plaque buildup or atherosclerosis. Atherosclerosis in the leg arteries causes peripheral vascular disease. The same process causes heart disease and stroke.