RESUMEN
G protein-coupled receptors(GPCRs)represent the largest class of cell surface receptors,mediating wide range of cellular and physiological processes through their transducers,G proteins and the-arrestins participate in almost all pathological processes. Recent technological advances are revolutionizing the utility of cryo-electron microscopy(cryo-EM),leading to a tremendous progress in the structural studies of biological macromolecules and cryo-EM has played a leading role in the structural biology of GPCR signaling complex. New discoveries of high-resolution threedimensional structures of GPCR signaling complexes based on cryo-EM have emerged vigorously,which depict the common structural characteristics of intermolecular interaction between GPCR and G protein complex-the conformational changes of the transmembrane helix 6 of receptors,and also demonstrate the structural basis of G protein subtype selectivity. Single-particle cryo-EM becomes an efficient tool for identifying the molecular mechanism of receptor-ligand interaction,providing important information for understanding GPCR signaling and the structure-based drug design.
Asunto(s)
Microscopía por Crioelectrón , Unión Proteica , Estructura Terciaria de Proteína , Receptores Acoplados a Proteínas G , QuímicaRESUMEN
Objective To evaluate the effects of the treatment for femoral neck fractures with closed reduction and cannulated screw fixation.Methods The results of stabilization of the femoral neck fracture with cannulated screws in 62 patients(25 male,37 female)from 2001to 2008 were reviewed retrospectively.The mean age of the patients was 68.6 years old.Results 55 patients(88.7%)had cured,30 patients were been cured,25 patients were been good healthy ,7patients were not cured.The duration of follow up was 8-62 months in 62 patients.Conclusion Closed reduction and internal fixation with cannulated screw is an effective method of minimally invasive,safety and inexpensive for femoral neck fractures.