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This study aimed at evaluating how encapsulation in a regular nanocarrier (NC) (providing extended circulation time) or in a brain-targeting NC (providing prolonged circulation time and increased brain uptake) may influence the therapeutic index compared with the unformulated drug and to explore the key parameters affecting therapeutic performance using a model-based approach. Pharmacokinetic (PK) models were built with chosen PK parameters. For a scenario where central effect depends on area under the unbound brain concentration curve and peripheral toxicity relates to peak unbound plasma concentration, dose-effect and drug-side effect curves were constructed, and the therapeutic index was evaluated. Regular NC improved the therapeutic index compared with the unformulated drug due to reduced peripheral toxicity, while brain-targeting NC enhanced the therapeutic index by lowering peripheral toxicity and increasing central effect. Decreasing drug release rate or systemic clearance of NC with drug still encapsulated could increase the therapeutic index. Also, a drug with shorter half-life would therapeutically benefit more from a NC encapsulation. This work provides insights into how a NC for brain delivery should be optimized to maximize the therapeutic performance and is helpful to predict if and to what extent a drug with certain PK properties would obtain therapeutic benefit from nanoencapsulation.  相似文献   
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Renal Denervation for Treatment of Cardiac Arrhythmias . It has now been more than a quarter of a century since modulation of the sympathetic nervous system was proposed for the treatment of cardiac arrhythmias of different origins. But it has also been some time since some of the early surgical attempts have been abandoned. With the development of ablation techniques, however, new approaches and targets have been recently introduced that have revolutionized our way of thinking about sympathetic modulation. Renal nerve ablation technology is now being successfully used for the treatment of resistant hypertension, but the indication spectrum might broaden and new therapeutic options might arise in the near future. This review focuses on the possible impact of renal sympathetic system modulation on cardiac arrhythmias, the current evidence supporting this approach, and the ongoing trials of this method in electrophysiological laboratories. We will discuss the potential roles that sympathetic modulation may play in the future.  相似文献   
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BACKGROUND Accurate detection of gastric infection by Helicobacter pylori(H.pylori) and premalignant lesions are important for effective provision of treatment,preventing the development of gastric neoplasia.Optical enhancement systems with optical magnification improved the identification of mucosal superficial and vascular patterns in patients with dyspepsia.AIM To evaluate an optical enhancement system with high-definition magnification,for diagnosis of normal gastric mucosa,H.pylori-associated gastritis,and gastric atrophy.METHODS A cross-sectional,nonrandomized study from November 2015 to April 2016 performed in a single-tertiary academic center from Ecuador.Seventy-two consecutive patients with functional dyspepsia according to the Rome III criteria,were tested for H.pylori using a stool antigen test and were assigned to an Hp+group or an Hp-control group.Esophagogastroduodenoscopy with highdefinition optical magnification and digital chromoendoscopy was performed,and patients were classified into 4 groups,in accordance to the microvasculararchitecture pattern of the mucosa.Interobserver and intraobserver agreement among operators were calculated.RESULTS Of the 72 participants,35 were Hp+ and 37 were Hp-.Among 10 patients with normal mucosal histology in biopsy samples,90% had a Type I pattern of microvascular architecture by endoscopy.Among participants with type IIa and type IIb patterns,significantly more were Hp+ than Hp-(32 vs 8),and most(31 out of 40) had histological diagnoses of chronic active gastritis.Two of the three participants with a histological diagnosis of atrophy had a type III microvascular pattern.The type I pattern predicted normal mucosa,type IIa–IIb predicted H.pylori infection,and type III predicted atrophy with sensitivities of 90.0%,91.4%,and 66.7%,respectively.The intraobserver and interobserver agreements had kappa values of 0.91 and 0.89,respectively.CONCLUSION High-definition optical magnification with digital chromoendoscopy is useful for diagnosis of normal gastric mucosa and H.pylori-associated gastritis with high accuracy,but further studies are needed to determine whether endoscopic diagnosis of gastric atrophy is feasible.  相似文献   
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通过探讨DRG支付方式改革下医院财务管理的应对策略,可以有效地降低医疗支付方式改革对医院财务管理的负面影响,促使医院财务管理在"危"与"机"的转换中抢抓机遇,促进医院财务管理提质增效。  相似文献   
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以培养创新型人才为目标,大连医科大学制定实施了“5+3”创新人才培养改革方案,以导师制培养为载体,在医学本科教育全过程中,制定分阶段创新能力培养体系,涵盖课程、讲座、实验设计、论文等基本科研能力训练,强化本科生科研能力培养。通过对首届“5+3”学生阶段性培养成果的统计学分析发现,“5+3”学生发表中文期刊、SCI,主持国家级创新项目、省级创新项目的比例均显著高于普通5年制学生,差异具有统计学意义(P<0.05)。虽然实施过程中存在一些问题和不足,但以导师制为核心的科研基础训练对提高学生科研思维和创新能力效果显著,对培养医学创新型人才具有可实施性。  相似文献   
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目的:基于中医传承软件系统探讨国医大师治疗心悸的用药规律。方法:收集整理《国医大师验案良方·心脑卷》中治疗心悸的病案并录入中医传承辅助平台,采用规则分析、改进互信息法、复杂系统熵聚类等数据挖掘方法,统计分析其中的用药规律。结果:分析纳入的83个病案得出149味中药,所用中药性味多为甘温,主要归心、肺、脾三经,包括丹参、黄芪、炙甘草、麦冬等高频次中药。提取置信度为1的丹参,五味子→麦冬组合,可窥见生脉饮的雏形并衍生出10个新方,新方可分为五类,分别为行气化痰类、滋阴养血类、温通心阳类、益气活血类和化痰祛瘀类。结论:国医大师治疗心悸有规律可循,主要以“益气通阳”“养阴补血”“化痰祛瘀”为组方规律,标本并治。  相似文献   
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