A protective glide for medical walker legs is disclosed in the present invention. The glazed element has at least one heating border on at least one face of at least one glass sheet, and the border is covered by the section and joined to the section by a heat-conducting seal. The pH-sensitive microspheres have a swelling transition with the pH range found in or near tumor tissue. Other, authenticated stations in the network will not communicate with the new station, but will pass the key request message to the network operator station. The GPU, in turn, includes a texture module, a vertex module and a fragment module.