RESUMEN
In this study, six different types of residential areas in Guiyang were selected as the research objects, including high-rise high-density, high-rise low-density, middle-rise high-density, middle-rise low-density, low-rise high-density and low-rise low-density. The indices of sunshine compliance rate and the building's sunshine hour ratio were constructed to compare and analyze sunshine environment across those six different residential areas. The factors influencing sunshine environment in different residential areas were studied. The results showed that the average sunshine compliance rates of the six types of residential areas were 36.9%, 61.9%, 20.6%, 69.6%, 26.5% and 45.0%, respectively. The average sunshine compliance rate of low-density residential areas was 2.25 times higher than that of high-density residential areas within the same type, among which the sunshine environment of low-density residential areas was better. The sunshine environment of different types of low-density residential areas was different. The sunshine hours for high-rise low-density and middle-rise low-density forms were concentrated in 5-6 hours, while the building's sunshine hour ratio was 0.24 and 0.32, respectively. The sunshine hours for low-rise low-density forms were mainly 6-7 hours, with a building's sunshine hour ratio of 0.28. Compared with other types of residential areas, the low-rise low-density type of sunlight environment was the best. The plot ratio was significantly positively correlated with the building's sunlight ratio of 0-1 h sunlight hours in the residential area.
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Luz Solar , ChinaAsunto(s)
Quiste Broncogénico/complicaciones , Laminectomía/métodos , Paraplejía/etiología , Vértebras Torácicas/patología , Quiste Broncogénico/diagnóstico , Quiste Broncogénico/cirugía , Diagnóstico Diferencial , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Paraplejía/diagnóstico , Paraplejía/cirugía , Vértebras Torácicas/cirugíaRESUMEN
BACKGROUND: Peripheral nerve injury is a common trauma, but presents a significant challenge to the clinic. Silk-based materials have recently become an important biomaterial for tissue engineering applications due to silk's biocompatibility and impressive mechanical and degradative properties. In the present study, a silk fibroin peptide (SF16) was designed and used as a component of the hydrogel scaffold for the repair of peripheral nerve injury. METHODS: The SF16 peptide's structure was characterized using spectrophotometry and atomic force microscopy, and the SF16 hydrogel was analyzed using scanning electron microscopy. The effects of the SF16 hydrogel on the viability and growth of live cells was first assessed in vitro, on PC12 cells. The in vivo test model involved the repair of a nerve gap with tubular nerve guides, through which it was possible to identify if the SF16 hydrogel would have the potential to enhance nerve regeneration. In this model physiological saline was set as the negative control, and collagen as the positive control. Walking track analysis and electrophysiological methods were used to evaluate the functional recovery of the nerve at 4 and 8 weeks after surgery. RESULTS: Analysis of the SF16 peptide's characteristics indicated that it consisted of a well-defined secondary structure and exhibited self-assembly. Results of scanning electron microscopy showed that the peptide based hydrogel may represent a porous scaffold that is viable for repair of peripheral nerve injury. Analysis of cell culture also supported that the hydrogel was an effective matrix to maintain the viability, morphology and proliferation of PC12 cells. Electrophysiology demonstrated that the use of the hydrogel scaffold (SF16 or collagen) resulted in a significant improvement in amplitude recovery in the in vivo model compared to physiological saline. Moreover, nerve cells in the SF16 hydrogel group displayed greater axon density, larger average axon diameter and thicker myelin compared to those of the group that received physiological saline. CONCLUSION: The SF16 hydrogel scaffold may promote excellent axonal regeneration and functional recovery after peripheral nerve injury, and the SF16 peptide may be a candidate for nerve tissue engineering applications.
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Hidrogel de Polietilenoglicol-Dimetacrilato/química , Regeneración Nerviosa/efectos de los fármacos , Péptidos/química , Andamios del Tejido/química , Animales , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Femenino , Fibroínas/química , Fibroínas/farmacología , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacología , Tamaño de la Partícula , Péptidos/farmacología , Ratas , Ratas Sprague-Dawley , Nervio Ciático/efectos de los fármacos , Nervio Ciático/lesiones , Nervio Ciático/ultraestructuraRESUMEN
OBJECTIVE: To explore the feasibility and efficacy of operating through an anterior approach in the treatment of dumbbell tumor complicating with vertebral destruction in cervical spine. METHODS: Surgical procedures were performed through an anterior approach in 7 cases of dumbbell tumor complicating with vertebral and transverse process destruction during the period of May 2004 to February 2009. Bone graft and internal fixation were implemented after tumor removal. RESULTS: In all 7 cases, tumors were resected completely and no recurrence occurred during a follow-up period of 6-46 months. The symptoms improved greatly postoperatively with fine fusion of graft bone. There was neither loose plate nor cervical instability. CONCLUSION: For huge dumbbell tumor with damaged vertebral body and transverse process in cervical spine, the anterior approach operation will remove tumor entirely and restore the stability of cervical spine so as to prevent spinal cord injury. It is an excellent option of treating dumbbell tumor in cervical spine.