RESUMEN
Specific detection of proteins is demonstrated using planar photonic crystal waveguides. Using immobilized biotin as probe, streptavidin was captured, causing the waveguide mode cut-off to red-shift. The device was shown to detect a 2.5 nm streptavidin film with a 0.86 nm cut-off red-shift. An improved photonic crystal waveguide sensor design is also described and shown to have a 40% improved bulk refractive index response.
Asunto(s)
Técnicas Biosensibles/instrumentación , Biotina/química , Óptica y Fotónica , Proteínas/química , Estreptavidina/química , Técnicas Biosensibles/métodos , Biotecnología/métodos , Cristalización , Diseño de Equipo , Fotones , Proteínas/análisis , Refractometría , SilicioRESUMEN
Sixty three 24 hour oesophageal pH studies were performed in children with known or suspected gastro-oesophageal reflux and their progress was followed for at least a year. Forty two studies were of children who were well at follow up who were not receiving medical treatment for gastro-oesophageal reflux, and had not required antireflux surgery. Twenty one studies were from children who were still on treatment for gastro-oesophageal reflux or had undergone antireflux surgery. The results were analysed using non-parametric statistics to assess the value of pH recordings in predicting which children were likely to have continuing problems. Sleep reflux (minutes/hour) and acid clearing time were the most highly significant variables (p less than 0.0005 and p less than 0.0001 respectively). The results suggest that either sleep gastro-oesophageal reflux of more than 6.4 minutes/hour or an acid clearing time of seven minutes or more are good predictors of the clinical outcome (specificity 88.1%, sensitivity 81.0%). Three of the five children with false positive results were under 10 months of age. Positive results in this age group should therefore be interpreted with caution.
Asunto(s)
Esófago/fisiopatología , Reflujo Gastroesofágico/diagnóstico , Adolescente , Niño , Preescolar , Reflujo Gastroesofágico/fisiopatología , Humanos , Concentración de Iones de Hidrógeno , Lactante , Monitoreo Fisiológico , Valor Predictivo de las PruebasAsunto(s)
Bencenosulfonatos/metabolismo , Colorantes de Alimentos/metabolismo , Absorción Intestinal , Animales , Bencenosulfonatos/síntesis química , Bencenosulfonatos/orina , Radioisótopos de Carbono , Heces/análisis , Femenino , Colorantes de Alimentos/síntesis química , Ratas , Distribución TisularAsunto(s)
Síndrome de Behçet , Adolescente , Adulto , Anciano , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/terapia , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
1. Steady state fever has been produced in rabbits with a priming injection followed by a sustaining infusion of homologous plasma containing endogenous pyrogen (EP). This fever appears to last as long as the infusion continues.2. Intravenous salicylate given 1 h after the start of the EP infusion produced only a small antipyretic effect. The same dose of salicylate given 4 h after the start of an EP infusion resulted in rapid and progressive defervescence. Intermediate antipyretic responses were obtained when salicylate was administered intravenously 2 and 3 h after the start of an EP infusion.3. Less than 1% of the systemic dose, when injected into a lateral cerebral ventricle, produced a significantly smaller response at 1 h than at 4 h after the start of an EP infusion. At both these times the fall in temperature following the intraventricular salicylate injection was dose dependent, but the slope of the dose-response line was significantly steeper at 4 h than at 1 hour.4. It is suggested that salicylates produce their antipyretic effects by antagonizing the action of EP within the nervous system, and that the hypothalamic EP concentration falls during the course of an EP infusion.