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1.
BackgroundGrossman described the ideal properties of root canal sealers. The International Organization for Standardization and American National Standards Institute and American Dental Association have codified some of his requirements in ISO 6876 and ANSI/ADA 57, respectively. In this narrative review, the authors combined the ideal Grossman properties and requirements of these standards, emphasizing the newer tricalcium silicate cement sealers. This chemical matrix for such sealers was developed on the basis of the success of bioactive mineral trioxide aggregate–type (tricalcium silicate cement) materials for enhanced sealing and bioactivity.MethodsThe authors searched the internet and databases using Medical Subject Heading terms and then conducted a narrative review of those articles involving the tricalcium silicate cement endodontic sealers.ResultsNinety-four articles were identified that discussed tricalcium silicate cement sealers. Tricalcium silicate cement sealers are partially antimicrobial and have bioactivity, which may presage improved biological sealing of the root canal system. Most other properties of tricalcium silicate cement sealers are comparable with traditional root canal sealers.ConclusionsWithin the limitations of this review, tricalcium silicate cement endodontic sealers met many of the criteria for ideal properties, such as placement, antimicrobial properties, and bioactivity, but limitations were noted in solubility, dimensional stability (shrinkage and expansion), and retrievability.Practical ImplicationsTricalcium silicate–based cements have been commercialized as bioactive, bioceramic endodontic sealers. Warm, cold, and single-cone obturation techniques are usable, depending on the commercial product. Some sealers can cause discoloration and are not easily retrievable, particularly when used to completely obturate a canal.  相似文献   
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【目的】 在“中国科技期刊卓越行动计划”实施三周年之际,有必要对我国科技期刊2035年迈入“世界第一方阵”目标的具体任务进行重新审视和预判,以进一步明确发展方向,动态调整推进思路。【方法】 采用国内外科技期刊、科技论文、科技期刊评价成果的系统性发展数据对科技期刊“世界第一方阵” 国家(或地区)在高水平科技期刊数量与质量层面的入围标准进行界定,在深入总结现有基础和优势的同时,对我国科技期刊综合实力与“世界第一方阵”国家(或地区)的现实差距进行逐一梳理和剖析,并对实现目标的可行性和推进思路进行研判和设计。【结果】 必须继续加强高水平英文科技期刊创办和培育力度、持续加大优秀中文科技期刊的建设强度、快速推进国内外科技期刊论文等质同效评价制度的建设与引导,并积极探索建立科学家和科研机构办好一流科技期刊的责任制度和贡献激励机制、创新发展编辑人才队伍培养与激励管理思路、深入实践灵活多样的期刊出版市场资本运作模式、稳步推进期刊出版市场机制和管理制度改革,为我国科技期刊事业的高质量发展提速增效。【结论】 虽然当前阶段目标任务艰巨,但迈入“世界第一方阵”未来可期。  相似文献   
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目的: 构建药学监护技能评分标准并探索其在教学中的应用。方法: 基于药物治疗管理工作步骤,建立课程教学的评分标准,并采用专家咨询法对评分标准进行修订。对62名临床药学专业学生进行药学监护相关案例演练,按照评分标准对学生药学监护能力进行评估。结果: 从采集信息、药物治疗问题、拟定和执行药物监护计划、执业记录4个方面建立了评分标准。案例演练结果显示学生在药物治疗问题部分表现最佳(得分率为75.91%±12.76%),其次是采集信息和拟定和执行药学监护计划部分(得分率分别为72.45%±10.70%,71.02%±9.80%),在执业记录部分表现最差(62.50%±6.57%)。各部分的难度系数为0.63~0.76。结论: 评分标准能切实反映学生药学监护能力的具体情况,有助于改进教学手段,可作为药学监护教学的重要教学工具,并为其他高校药学监护教育评估提供参考。  相似文献   
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The adrenal cortex gives rise to a biologically heterogenous group of neoplasms, each with a distinct morphology, antigen expression and molecular profile. Adrenal cortical adenomas have excellent prognosis and are usually cured by surgical resection alone, while adrenal cortical carcinomas are very aggressive tumors with a poor prognosis regardless of therapy. These tumors are rare and often challenging for a pathologist to diagnose, as significant overlap exists between benign and malignant lesions in some cases. In this review, we attempt to summarize most important histologic and clinical features of adrenal cortical adenomas and carcinomas, clarify the use of different grading systems, the use of special stains and the differential diagnosis for practicing pathologists. Most relevant hereditary syndromes associated with adrenal cortical tumors are listed. Updates in molecular alterations in adrenal cortical neoplasms and hyperplastic diseases as well as their clinical significance and potential therapeutic implications are also discussed.  相似文献   
6.
Introduction and objectivesOur objective was to approximate the prevalence of mutations in candidate genes for familial hypercholesterolemia (FH) in a middle-aged Spanish population and to establish the predictive value of criteria for clinical suspicion in the detection of causative mutations.MethodsUnrelated individuals aged ≥ 18 years from the Aragon Workers’ Health Study (AWHS) with high low-density lipoprotein cholesterol (LDL-C) and clinical suspicion of FH (participants with LDL-C concentrations above the 95th percentile, participants with premature cardiovascular disease and/or participants with high LDL-C [130 mg/dL] under statin therapy), assuming that any participant with FH exhibits at leats 1 trait, were selected and the LDLR, APOB, PCSK9, APOE, STAP1 and LDLRAP1 genes were sequenced by next generation sequencing technology.ResultsOf 5400 individuals from the AWHS, 4514 had complete data on lipid levels and lipid-lowering drugs, 255 participants (5.65%) met the criteria for suspicion of FH, 24 of them (9.41%) were diagnosed with hyperlipoproteinemia(a), and 16 (6.27% of those sequenced) were found to carry causative mutations in candidate genes: 12 participants carried 11 different pathogenic LDLR alleles and 4 participants carried 1 pathogenic mutation in PCSK9. LDL-C concentrations > 220 mg/dL and LDL-C > 130 mg/dL despite statin therapy showed the strongest association with the presence of mutations (P = .011).ConclusionsOur results show that the prevalence of FH in Spain is 1:282 and suggest that the combination of high untreated LDL-C and high levels of LDL-C despite statin therapy are the best predictors of a positive FH genetic test.  相似文献   
7.
Acute liver failure (ALF) refers to a state of severe hepatic injury that leads to altered coagulation and sensorium in the absence of pre-existing liver disease. ALF has different causes, but the clinical characteristics are strikingly similar. In clinical practice, however, inconsistency in the definition of ALF worldwide and confusion regarding the existence of pre-existing liver disease raise diagnostic dilemmas. ALF mortality rates used to be over 80% in the past; however, survival rates on medical treatment have significantly improved in recent years due to a greater understanding of pathophysiology and advances in critical care management. The survival rates in acetaminophen-associated ALF have become close to the post-transplant survival rates. Given that liver transplantation (LT) is an expensive treatment that involves a major surgical operation in critically ill patients and lifelong immunosuppression, it is very important to select accurate patients who may benefit from it. Still, emergency LT remains a lifesaving procedure for many ALF patients. However, there is a lack of consistency in current prognostic models that hampers the selection of transplant candidates in a timely and precise manner. The other problems associated with LT in ALF are the shortage of graft, development of contraindications on the waiting list, vaguely defined delisting criteria, time constraints for pre-transplant evaluation, ethical concerns, and comparatively poor post-transplant outcomes in ALF. Therefore, there is a desperate need to establish accurate prognostic models and explore the roles of evolving adjunctive and alternative therapies, such as liver support systems, plasma exchange, stem cells, auxiliary LT, and so on, to enhance transplant-free survival and to fill the void created by the graft shortage  相似文献   
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翁星 《现代肿瘤医学》2022,(16):2995-2998
目的:评估剂量计算网格和γ评估标准对三维晶格放疗(lattice radiotherapy,LRT)剂量验证的影响,并确定合适的剂量计算网格和γ评估标准。方法:回顾性选取14例行LRT放疗的肿瘤患者计划,并移植到Delta4三维剂量验证模体上,使用4种剂量计算网格(1 mm、1.5 mm、2 mm和2.5 mm)创建验证计划。在4种评估标准(2%/2 mm、2%/3 mm、3%/2 mm和3%/3 mm)下进行剂量验证并获得γ通过率。最后,使用Kruskal-Wallis检验分析数据。结果:2%/2 mm和3%/2 mm评估标准的γ通过率低于2%/3 mm和3%/3 mm评估标准,2 mm和2.5 mm计算网格的γ通过率低于1 mm和1.5 mm计算网格(P<0.05)。结论:剂量计算网格和γ评估标准影响了LRT计划剂量验证中γ通过率的准确性,LRT验证计划宜采用1.5 mm或更小的计算网格和3%/2 mm或更严格的γ评估标准。  相似文献   
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目的]观察新的心电图诊断标准RLⅠ+SV4、SD+SV4是否适用于高血压合并左心室肥厚(LVH)的诊断,研究13项心电图诊断标准以及新标准与常用标准联合应用对于高血压合并LVH的临床价值。[方法]以超声心动图测定的左心室质量指数(LVMI)为标准,选取原发性高血压或者有高血压治疗史的住院患者280例,其中高血压合并LVH患者94例(LVH组),左心室正常患者186例(左心室正常组)。同步记录12导联心电图。绘制各种心电图诊断标准的受试者工作特征曲线(ROC),比较ROC的曲线下面积(AUC)。计算各种诊断标准的灵敏度和特异度。分析RLⅠ+SV4、SD+SV4及其联合目前公认的心电图诊断LVH标准对高血压患者合并LVH的诊断价值。[结果]单个心电图导联中,RLⅠ即Ⅰ导联的R波是较好预测LVH的因子之一(AUC=0.63,P<0.01)。两个导联振幅相加诊断LVH的研究中,RLⅠ+SV4标准(AUC=0.64,P<0.01)的灵敏度为50%,特异度为71%;配对卡方检验显示RLⅠ+SV4诊断LVH与金标准(LVMI判定LVH)之间无明显统计学差异。SD+SV4标准(AUC=0.59,P<0.05)的灵敏度为31%,特异度为87%,其中SD波为12导联中拥有最大振幅的S波。RLⅠ+SV4联合Sokolow-Lyon电压标准能够提高诊断高血压合并LVH的灵敏度,其灵敏度为59%,特异度为60%。[结论]RLⅠ+SV4标准具有较高的AUC,适合高血压患者合并LVH的初步筛查;RLⅠ+SV4联合Sokolow-Lyon电压标准能够提高诊断的灵敏度。SD+SV4标准临床适用性没有RLⅠ+SV4标准高。  相似文献   
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