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1.
目的探讨腰丛联合坐骨神经阻滞对高龄髋关节置换术患者术后疼痛的缓解作用及对认知功能的保护机制。 方法选取2016年6月至2018年5月于海南省万宁市人民医院行单次全髋关节置换术的高龄患者120例,年龄80~100岁,纳入标准:年龄范围为80~100岁,美国麻醉医师协会(ASA)分级Ⅱ~Ⅲ级;符合全髋关节置换术相关手术指征;认知功能正常。排除标准:合并严重原发疾病者;合并精神病或神经系统疾病者;依从性较差者;对本研究麻醉方案过敏者。所有患者采用随机数字表法分为两组:全身麻醉组(GA组),腰丛-坐骨神经阻滞组(PCSNB组),每组各60例。比较两组术中情况(麻醉操作时间、手术时间、术中出血量、术中补液量),手术前后血清碱性成纤维细胞生长因子(bFGF)水平。采用视觉模拟量表(VAS)评估两组患者术后疼痛程度,采用简易精神状态量表(MMSE)及蒙特利尔认知评估量表(MoCA)评估两组患者认知功能。正态分布的计量资料采用t检验,同一指标在3个以上不同时间点上比较,采用重复测量方差分析。 结果PCSNB组麻醉操作时间显著高于GA组(t=17.74,P<0.001),术中出血量及术中补液量均显著低于GA组(t=7.56、14.59、7.60,均为P<0.001)。术后1 d两组血清bFGF水平均有所下降(t=13.14、6.82,均为P<0.001),但PCSNB组血清bFGF水平显著高于GA组(t=7.43,P <0.001)。PCSNB组术后2、12及24 h的VAS评分显著低于对照组(F=8.03、6.56,均为P <0.001)。术后1 d,PCSNB组MMSE评分及MoCA评分均显著低于对照组(t=3.89、4.58,均为P <0.001)。 结论腰丛联合坐骨神经阻滞可减轻高龄髋关节置换术患者术后疼痛,对患者认知功能具有保护作用,可能与bFGF水平有关。  相似文献   
2.
Corti器的感音过程容易受到内部结构属性变化的影响。外柱细胞血管舒张刺激磷蛋白缺失会减缓肌动蛋白丝的形成,从而产生听力延迟。本研究运用COMSOL建立三维有限元模型研究肌动蛋白缺失导致外柱细胞软化时,Corti器感音过程中基底膜和外毛细胞与Deiters细胞结合点的力学行为变化。结果表明,外柱细胞软化会削弱外毛细胞主动力对基底膜位移增益的放大作用,但削弱作用并不会立即产生,Corti器存在维持正常功能的"缓冲"阶段。在100 dB和120 dB之间可能存在一个声压级临界值,在该临界值两侧外柱细胞软化对基底膜应力变化的影响是截然相反的。另外外柱细胞软化对不同外毛细胞与Deiters细胞结合点力学行为的影响也不同,位移增益优先级会因此产生改变。  相似文献   
3.
目的评价现有镍钛锉在根管预备中的使用效果,探讨根管预备中锉的最佳使用顺序。方法使用Excel 2016,推导特定直径和锥度的锉表面积和体积计算公式。以根管体积和表面积增长率为主要指标,结合折线图和锥度坐标图进行数值模拟。结果在纳入的现有26种根管锉产品中,vTaper推荐的预备顺序平均体积增长率最低。3+1 (即1根通道锉与3根成形锉)、3+2 (即2根通道锉与3根成形锉)、4+1 (即1根通道锉与4根成形锉)以及4+2 (即2根通道锉与4根成形锉)共4种模式对应的最佳根管锉使用顺序依次为2002—2003—2004—2504—3004、 2002—1803—1804—2004—2504—3004、 2002—1703—1704—2004—2504—3004;2002—1503—1703—1704—2004—2504—3004。结论根据数据模拟,纳入的现有镍钛锉系统中,使用#20 K锉的vTaper系统的预备顺序最佳。通过推导得出的4种最佳顺序的根管体积和表面积增长率的平均值和方差明显小于大多数现有的系统,为后续实验提供基础,并有助于提高根管治疗的成功率,减少并发症。  相似文献   
4.
BackgroundThe new software, mediCAD® 3D Knee Sport (mediCAD Hectec GmbH, Altdorf/Landshut, Germany), promises to combine automated digital 3D bone model generation, 3D analysis of lower limb geometry including analysis of the patellofemoral joint, and osteotomy planning. The aim of this study was to evaluate its reliability and accuracy.MethodsIn this retrospective multi-observer study, three post-mortem CTs were analysed by three observers at three points in time. Reliability was evaluated by calculating the intraclass correlation coefficient (ICC) of interobserver agreement. Accuracy was evaluated using the mean deviation D from the mean and the standard deviation SD from D.ResultsTen of 18 alignment parameters showed excellent, two good and three moderate interobserver agreement. Poor agreement was found for the mechanical medial proximal tibial angle, the trochlear sulcus angle and trochlea depth. Mean interobserver ICC of all parameters ranged from 0.32 to 0.99. Fifteen of 18 parameters showed a low mean deviation D from the mean of < 2 mm / 2°. Three parameters related to the patellofemoral joint showed medium or high D (patella tilt, trochlear sulcus angle, patellar ridge angle). These parameters also showed the highest values for the SD of D. The trochlear sulcus angle was found to be the only parameter with high mean deviation (D ≥ 5 mm/5°) with D being 5.67 ± 3.23°.ConclusionsThe current version of the software achieves good interobserver reliability and accuracy with the exception of a few measurement parameters.  相似文献   
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6.
Three-dimensional surgical planning is used widely in orthognathic surgery. Although numerous computer programs exist, the accuracy of soft tissue prediction remains uncertain. The purpose of this study was to compare the prediction accuracy of Dolphin, ProPlan CMF, and a probabilistic finite element method (PFEM). Seven patients (mean age 18 years; five female) who had undergone Le Fort I osteotomy with preoperative and 1-year postoperative cone beam computed tomography (CBCT) were included. The three programs were used for soft tissue prediction using planned and postoperative maxillary position, and these were compared to postoperative CBCT. Accurate predictions were obtained with each program, indicated by root mean square distances: RMSDolphin = 1.8 ± 0.8 mm, RMSProPlan = 1.2 ± 0.4 mm, and RMSPFEM = 1.3 ± 0.4 mm. Dolphin utilizes a landmark-based algorithm allowing for patient-specific bone-to-soft tissue ratios, which works well for cephalometric radiographs but has limited three-dimensional accuracy, whilst ProPlan and PFEM provide better three-dimensional predictions with continuous displacements. Patient or population-specific material properties can be defined in PFEM, while no soft tissue parameters are adjustable in ProPlan. Important clinical considerations are the topological differences between predictions due to the three algorithms, the non-negligible influence of the mismatch between planned and postoperative maxillary position, and the learning curve associated with sophisticated programs like PFEM.  相似文献   
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8.
Forest biomass (FB) is widely used overseas as an industrial energy source, particularly in Europe, but is currently little used in Australia. Typical attributes of FB disadvantage it as a fuel relative to traditional energy sources: high moisture content, low bulk density, spatial and temporal dispersion, low value and low energy content. As such, minimising FB delivered costs will be critical to further development of Australian forest biomass supply chains (FBSC).

The paper reviews published international and Australian research into the key FBSC elements (biomass source, primary transport, storage, secondary transport and processing) focussing on areas where Australian FBSCs could potentially apply the research to reduce costs and where additional Australian research is required. Logging residue (LR) was identified as the FB resource in Australia with the greatest potential for use as biofuel. Rapid infield drying of LR in Australian studies suggests that infield drying could be used to reduce secondary transport costs, which can be a significant part of the delivered FB costs. However, further development of Australian FBSC models supported by research into primary and secondary transport costs, drying and chipper performance will be required to identify trade-offs between potential FBSC costs and benefits and to facilitate forest managers’ decision-making processes regarding the establishment and running of FBSCs.  相似文献   
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BackgroundAlthough measles is endemic throughout the World Health Organization European Region, few studies have analysed socioeconomic inequalities and spatiotemporal variations in the disease’s incidence.AimTo study the association between socioeconomic deprivation and measles incidence in Germany, while considering relevant demographic, spatial and temporal factors.MethodsWe conducted a longitudinal small-area analysis using nationally representative linked data in 401 districts (2001–2017). We used spatiotemporal Bayesian regression models to assess the potential effect of area deprivation on measles incidence, adjusted for demographic and geographical factors, as well as spatial and temporal effects. We estimated risk ratios (RR) for deprivation quintiles (Q1–Q5), and district-specific adjusted relative risks (ARR) to assess the area-level risk profile of measles in Germany.ResultsThe risk of measles incidence in areas with lowest deprivation quintile (Q1) was 1.58 times higher (95% credible interval (CrI): 1.32–2.00) than in those with highest deprivation (Q5). Areas with medium-low (Q2), medium (Q3) and medium-high deprivation (Q4) had higher adjusted risks of measles relative to areas with highest deprivation (Q5) (RR: 1.23, 95%CrI: 0.99–1.51; 1.05, 95%CrI: 0.87–1.26 and 1.23, 95%CrI: 1.05–1.43, respectively). We identified 54 districts at medium-high risk for measles (ARR > 2) in Germany, of which 22 were at high risk (ARR > 3).ConclusionSocioeconomic deprivation in Germany, one of Europe’s most populated countries, is inversely associated with measles incidence. This association persists after demographic and spatiotemporal factors are considered. The social, spatial and temporal patterns of elevated risk require targeted public health action and policy to address the complexity underlying measles epidemiology.  相似文献   
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