GNSS广泛地应用于各行各业,但是存在卫星导航信号落地功率低,极易受到各种有意和无意的电磁干扰影响,会对卫星导航应用造成严重的威胁.随着卫星导航的广泛应用,卫星导航信号受干扰问题引起了国际的广泛关注.全球卫星导航系统国际委员会(...GNSS广泛地应用于各行各业,但是存在卫星导航信号落地功率低,极易受到各种有意和无意的电磁干扰影响,会对卫星导航应用造成严重的威胁.随着卫星导航的广泛应用,卫星导航信号受干扰问题引起了国际的广泛关注.全球卫星导航系统国际委员会(International Committee on Global Navigation Satellite Systems,ICG)为此成立了专门的卫星导航干扰检测与削弱(IDM)工作组,旨在开展各国在该领域的政策法规、相关技术及IDM系统建设的研讨与交流.本文介绍和分析了ICG IDM的重要进展及研究态势,并对干扰检测定位理论技术及国内外卫星导航干扰监测系统的研究进展进行了梳理,对深化卫星导航干扰监测的理论与技术研究及保障卫星导航安全具有重要的技术借鉴与研究支撑.展开更多
The aim of this experiment was to investigate the ameliorative effect and molecular mechanism of tilapia head glycolipid(TH-GL)on indomethacin(IDM)-induced gastric ulcer in male Sprague Dawley(SD)rats.The gastric ulce...The aim of this experiment was to investigate the ameliorative effect and molecular mechanism of tilapia head glycolipid(TH-GL)on indomethacin(IDM)-induced gastric ulcer in male Sprague Dawley(SD)rats.The gastric ulcer model was established by oral administration of 30mgkg^(-1) IDM after 7 days of TH-GL or omeprazole(OME)administration in rats.Then the macroscopic gastric injury symptoms,gastric mucosa protective factor cyclooxygenase 1(COX-1),cyclooxygenase 2(COX-2),prostaglandin E_(2)(PGE_(2)),the levels of oxidative stress,and inflammatory cytokine expression levels in the rats were analyzed.The experimental results showed that multiple ulcers appeared on the gastric surface of the rats in the model group.Compared to the model group,TH-GL significantly alleviated gastric ulcers and reduced the gastric damage index in rats.In addition,TH-GL significantly promoted the expression of constitutive enzyme COX-1 while inhibited the expression of inducible enzyme COX-2,and make PGE2 maintain at normal levels.TH-GL also inhibited oxidative stress and inflammatory responses,increased superoxide dismutase(SOD)activity and glutathione(GSH)content,decreased the level of malondialdehyde(MDA)and the content of pro-inflammatory factor.In conclusion,these results suggested that TH-GL could maintain the expression levels of COX-1 and PGE2 while inhibit the expression of COX-2 in the gastric of rat and then prevent IDM-induced gastric ulcer,which may be related to the regulation of oxidative stress and inflammatory response.Therefore,TH-GL might be a new option for the prevention of gastric diseases induced by IDM.展开更多
目的:采用Waters C18柱(5μm,4.6*250 mm),以磷酸盐缓冲液(取磷酸二氢铵11.5 g,加适量水使其溶解,加磷酸1 m L,用水稀释至1000 m L)-乙腈(80∶20)为流动相。流速1.0 mL/min,检测波长为262,柱温为30℃条件下,建立高效液相色谱(HPLC)测定...目的:采用Waters C18柱(5μm,4.6*250 mm),以磷酸盐缓冲液(取磷酸二氢铵11.5 g,加适量水使其溶解,加磷酸1 m L,用水稀释至1000 m L)-乙腈(80∶20)为流动相。流速1.0 mL/min,检测波长为262,柱温为30℃条件下,建立高效液相色谱(HPLC)测定马来酸氯苯那敏的方法。结果表明,马来酸氯苯那敏的进样量在20.272~141.904μg范围内有良好的线性关系,回归方程y=0.1153x-0.0162(R=0.9999),方法回收率为99.19%~101.68%之间,RSD为0.9%。6批样品的马来酸氯苯那敏含量在98.97%~101.58%之间;结论:此方法专属性强,精密度稳定性良好,准确度较高,可用于该制剂中马来酸氯苯那敏的含量测定。展开更多
文摘GNSS广泛地应用于各行各业,但是存在卫星导航信号落地功率低,极易受到各种有意和无意的电磁干扰影响,会对卫星导航应用造成严重的威胁.随着卫星导航的广泛应用,卫星导航信号受干扰问题引起了国际的广泛关注.全球卫星导航系统国际委员会(International Committee on Global Navigation Satellite Systems,ICG)为此成立了专门的卫星导航干扰检测与削弱(IDM)工作组,旨在开展各国在该领域的政策法规、相关技术及IDM系统建设的研讨与交流.本文介绍和分析了ICG IDM的重要进展及研究态势,并对干扰检测定位理论技术及国内外卫星导航干扰监测系统的研究进展进行了梳理,对深化卫星导航干扰监测的理论与技术研究及保障卫星导航安全具有重要的技术借鉴与研究支撑.
基金supported by the National Key R&D Pro-grams of China(No.2018YFD0901103)the Hainan Provincial Natural Science Foundation of China(No.2019 RC093).
文摘The aim of this experiment was to investigate the ameliorative effect and molecular mechanism of tilapia head glycolipid(TH-GL)on indomethacin(IDM)-induced gastric ulcer in male Sprague Dawley(SD)rats.The gastric ulcer model was established by oral administration of 30mgkg^(-1) IDM after 7 days of TH-GL or omeprazole(OME)administration in rats.Then the macroscopic gastric injury symptoms,gastric mucosa protective factor cyclooxygenase 1(COX-1),cyclooxygenase 2(COX-2),prostaglandin E_(2)(PGE_(2)),the levels of oxidative stress,and inflammatory cytokine expression levels in the rats were analyzed.The experimental results showed that multiple ulcers appeared on the gastric surface of the rats in the model group.Compared to the model group,TH-GL significantly alleviated gastric ulcers and reduced the gastric damage index in rats.In addition,TH-GL significantly promoted the expression of constitutive enzyme COX-1 while inhibited the expression of inducible enzyme COX-2,and make PGE2 maintain at normal levels.TH-GL also inhibited oxidative stress and inflammatory responses,increased superoxide dismutase(SOD)activity and glutathione(GSH)content,decreased the level of malondialdehyde(MDA)and the content of pro-inflammatory factor.In conclusion,these results suggested that TH-GL could maintain the expression levels of COX-1 and PGE2 while inhibit the expression of COX-2 in the gastric of rat and then prevent IDM-induced gastric ulcer,which may be related to the regulation of oxidative stress and inflammatory response.Therefore,TH-GL might be a new option for the prevention of gastric diseases induced by IDM.
文摘目的:采用Waters C18柱(5μm,4.6*250 mm),以磷酸盐缓冲液(取磷酸二氢铵11.5 g,加适量水使其溶解,加磷酸1 m L,用水稀释至1000 m L)-乙腈(80∶20)为流动相。流速1.0 mL/min,检测波长为262,柱温为30℃条件下,建立高效液相色谱(HPLC)测定马来酸氯苯那敏的方法。结果表明,马来酸氯苯那敏的进样量在20.272~141.904μg范围内有良好的线性关系,回归方程y=0.1153x-0.0162(R=0.9999),方法回收率为99.19%~101.68%之间,RSD为0.9%。6批样品的马来酸氯苯那敏含量在98.97%~101.58%之间;结论:此方法专属性强,精密度稳定性良好,准确度较高,可用于该制剂中马来酸氯苯那敏的含量测定。
