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101.
Glutamate receptors within the nucleus of solitary tract contribute to pancreatic secretion stimulated by intraduodenal hypertonic saline 下载免费PDF全文
High-speed counter-current chromatography (HSCCC) with a solvent system composed of ethyl acetate-n-buta- nol-water (2 : 1 : 3, V/V/V) was used to isolate and separate two C-glycosylflavones from Patrinia villosa Juss, a traditional Chinese medicine. The separation produced 42.9 mg isovitexin and 20.1 mg isoorientin with purities of 99.3% and 98.5%, respectively as determined by high-performance liquid chromatography (HPLC) in one step elution from 250 mg crude extract, and identification was performed by MS, ^1H NMR and ^13C NMR. It is the first report of discovering isovitexin and isoorientin from the plant of Patrinia genus. 相似文献
102.
文章结合实践介绍了实验动物和脏器标本的摄影方法及注意事项,为从事这方面工作的科技人员提供了技术支持。 相似文献
103.
关于802.1X认证技术在校园网应用中问题的探讨 总被引:2,自引:0,他引:2
介绍了802.1X认证技术的体系结构和工作原理,分析了802.1X认证技术在校园网中应用的优势与不足. 相似文献
104.
乌司他丁对原位肝移植术肺损伤的保护作用 总被引:1,自引:0,他引:1
目的:观察原位肝移植术(OLT)中肺损伤的程度,探讨乌司他丁(UTI)对OLT中肺损伤的保护作用.方法:40例择期行OLT手术患者随机分为UTI组和对照组各20例,UTI组(n=20)切皮后将UTI 100万单位加入100mL生理氯化钠溶液,持续静脉输注,之后每隔4 h重复使用.对照组(n=20)以等容量生理氯化钠溶液代替.于麻醉后切皮前、无肝前期120 min、无肝期30 min、新肝期10 min、新肝期60 min和术毕对肺顺应性、吸气阻力、呼气阻力、峰值压力和平台压力进行观察.结果:在新肝期10 min、新肝期60 min和术毕时,对照组的肺顺应性显著下降,吸气阻力、呼气阻力、峰值压力和平台压力显著升高(P<0.05).UTI组的吸气阻力、呼气阻力、峰值压力和平台压力值均明显低于对照组(P<0.05),而肺顺应性值明显高于对照组(P<0.05).结论:0LT过程造成肺损伤,UTI在OLT中对肺损伤有保护作用. 相似文献
105.
106.
目的:探讨影像组学方法在术前预测直肠非黏液性腺癌淋巴结转移中的价值。方法:回顾性分析91例手术病理切片证实为直肠非黏液性腺癌患者的影像学资料,其中61例为训练样本,30例为验证样本。基于全瘤体积,从每个原发病灶术前高分辨T2加权成像(T2-weighted imaging,T2WI)图像中提取影像组学特征1 301个。基于训练样本,利用最小绝对收缩和选择算子(the least absolute shrinkage and selection operator,LASSO)逻辑回归方法筛选关键特征并构建影像组学分类器。采用受试者工作特征(receiver operating characteristic,ROC)曲线评价影像组学分类器的辨别效能,并将其与形态学标准进行比较。在验证样本中验证影像组学分类器的价值。结果:由5个影像组学特征构建的分类器与淋巴结转移状态有关(P<0.001)。在训练样本和验证样本中,影像组学分类器诊断淋巴结转移的曲线下面积分别为0.874(95% CI:0.787~0.960)和0.878(95% CI:0.727~1.000),形态学标准诊断淋巴结转移的曲线下面积分别为0.619(95% CI:0.487~0.752)和0.556(95% CI:0.355~0.756)。无论是训练样本还是验证样本,影像组学分类器的诊断效能均高于形态学标准(均P<0.05)。结论:影像组学分类器可术前个体化预测直肠非黏液性腺癌淋巴结转移,而且其诊断效能高于形态学标准。 相似文献
107.
目的 通过扎根理论研究构建患者视角的预检分诊服务满意度理论框架,为评估和量化患者对预检分诊服务的满意度提供参考。方法 采用目的抽样和理论抽样的方法,选择27例接受过预检分诊服务的患者进行半结构式深度访谈;运用程序化扎根理论的研究方法,采用NVIVO12.0软件辅助对原始数据进行开放式编码、主轴编码及选择性编码,并进行理论饱和度检验。结果 析出患者期望、服务质量、信息供给、人本关怀、持续改进5个主范畴。结论 5个主范畴分别构成预检分诊服务满意度的主体因素、核心因素、关键因素、基本因素和保障因素。该理论框架可为改善预检分诊服务、评估患者满意度提供参考。 相似文献
108.
Lignin, one of the main components of lignocellulose, can be used as an alternative to chemical polyols in the production of polyurethane because of its abundant phenolic and alcohol hydroxyls. Traditionally, lignin is directly applied in the preparation of polyurethane; however, modified lignin has been proved to be superior, especially that obtained by the oxypropylation reaction. Therefore, lignopolyol obtained by mild and efficient oxypropylation was utilized in the production of rigid polyurethane foam in this study. Specifically, the effects of the content of lignopolyol on the chemical structure, morphological structure, mechanical properties and thermal stability of the lignin-based rigid polyurethane foam were investigated. It was found that the compressive strength of the rigid polyurethane foam was significantly improved with the addition of lignopolyol compared with that of the pure polyurethane foam, which was attributed to the fact that oxypropylation made lignin into highly branched and functionalized polyols by transforming all phenolic hydroxyls into aliphatic hydroxyls. Moreover, when the molal weight of lignopolyol accounted for 40% of the added polyols, the generated foam showed optimal uniformity and regularity, and the compressive strength reached 0.18 MPa, meeting the requirements of industrial application, below which, the amount of undesired reactions is bound to increase. As a consequence, the added amount of lignopolyol was increased as much as possible on the basis of guaranteeing the desired properties, which was more conducive to realizing the green degradation and economic synthesis of rigid polyurethane foam.Lignin-based polyurethane foam with excellent performance could be produced with the lignopolyol prepared by mild and efficient oxypropylation. 相似文献
109.
Ying Fu Rengui Saxu Kadir Ahmad Ridwan Cai Zhao Xiangshun Kong Yao Rong Weida Zheng Peng Yu Yuou Teng 《RSC advances》2022,12(34):21821
Axitinib is a potent vascular endothelial growth factor receptor (VEGFR) inhibitor, which has a strong inhibitory effect on the three isoforms of VEGFR 1–3. Having strong therapeutic efficacy, its broad use is limited by its side effects such as hypertension, proteinuria, cardiovascular damage, and liver and kidney dysfunction. Selenium compounds are broadly reported to have a good protective effect on cardiovascular disease, inflammation, infection, and immune function. In this study, a selenium substitute of axitinib was synthesized, and its anti-renal cell carcinoma activity and side effects were investigated. The results of the study indicated that Se-axitinib had potent antitumor activity on renal cell carcinoma (RCC), alleviated vascular hyperpermeability, and also alleviated axitinib-related side effects including hypertension, liver dysfunction and kidney dysfunction significantly. Therefore, we suggest that Se-axitinib could be a solution to the severe side effects of VEGFR inhibitors and provide evidence to improve the outcome of RCC treatment.Se-axitinib is a selenium substitution of sulfur in axitinib, which reduced the side effect of VEGFR inhibitors and maintained the potent anticancer activity of the original drug. 相似文献
110.
目的:分析西宁地区常见蝇种季节消长规律、蝇种构成及影响因素.方法:臭豆腐诱饵法.结果:西宁地区的优势蝇种为厩腐蝇、新陆原腐蝇、常齿股蝇、红头丽蝇、大头金蝇、丝光绿蝇、舍蝇、尾黑麻蝇等,蝇密度高峰期在6、7、8月份.结论:滋生环境的改变和综合治理措施的运用,会改变城市的优势蝇种构成,持续的暖冬是导致蝇种消长规律变化的主要原因. 相似文献