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.
Nerve block. The nerve block is a physiological test that determines whether the patient's pain is mediated by the targeted nerve, i.e. one or more of the medial branches of the dorsal rami that innervate the posterior elements of the cervical spine including the intervertebral discs, the zygapophyseal joints, and the posterior neck muscles.