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71.
Porous anodic alumina oxide (AAO) obtained via two-step anodization is a material commonly used as a template for fabricating 1D nanostructures. In this work, copper and cobalt-iron 1D nanocones were obtained by an electrodeposition method using AAO templates. The templates were produced using two-step anodization in H2C2O4. The Co–Fe nanostructures are characterized by homogeneous pore distribution. The electrocatalytic activity of the produced nanomaterials was determined in 1 M NaOH using the linear sweep voltammetry (LSV) and chronopotentiometry (CP) methods. These materials can be used as catalysts in the water-splitting reaction. The sample’s active surface area was calculated and compared with bulk materials.  相似文献   
72.
IntroductionPerioperative symptoms such as pain, nausea and anxiety are often inadequately treated. We conducted a pragmatic trial to evaluate the impact of Complementary and Alternative Medicine (CAM) treatments on these symptoms, within the framework of a general surgery department that integrates CAM.MethodsPatients ≥ 18 years referred to CAM treatments by surgical medical staff were allocated to standard of care with CAM treatment (CAM group) or without, according to patient preference and practitioner availability. CAM treatments included Acupuncture, Reflexology, or Guided Imagery. The primary outcome variable was the change from baseline in symptom severity, measured by Visual Analogue Scale (VAS). Patients and practitioners were asked to report any adverse effects associated with CAM treatments.ResultsA total of 1127 patients were enrolled, 916 undergoing 1214 CAM treatments and 211 controls. Socio-demographic characteristics were similar in both groups. Patients in the CAM group had more severe baseline symptoms. Symptom reduction was greater in the CAM group compared with controls, with a mean reduction in pain of −2.17 ± 2.4 vs −0.29 ± 2 (P < 0.0001); nausea −1.2 ± 2.42 vs −0.3 ± 1.94 (P < 0.0001); and anxiety −2.23 ± 2.76 vs −0.03 ± 2.54 (P < 0.0001). Acupuncture was more effective for nausea control. No significant adverse events were reported with any of the CAM therapies.ConclusionCAM treatments provide additional relief to Standard Of Care (SOC) for perioperative symptoms. Larger randomized control trial studies with longer follow-ups are needed to confirm these benefits. The study is registered with clinical trials.gov at (NCT01733771).  相似文献   
73.
目的 探讨基于中国人脑图谱Chinese2020配准的静息态功能MR数据分析在阿尔茨海默病(AD)患者中的应用价值。方法 收集12例AD患者(AD组)和17名健康志愿者(正常对照组),基于中国人脑图谱Chinese2020和传统标准脑图谱ICBM152配准对静息态数据进行全脑分析,运用低频振幅(ALFF)和局部一致性(ReHo)分析方法,评估AD患者脑局部神经元自发活动的变化,并比较基于2种脑图谱配准计算的AD患者ALFF和ReHo差异性脑区的分布。结果 基于2种脑图谱的数据分析均发现,与正常对照组比较,AD组右侧颞上回、右侧楔前叶和右侧角回ALFF值减低,左侧小脑、左侧颞极、颞上回和颞中回ALFF升高(P均<0.05);AD组左侧颞中回、右侧颞下回、左侧三角部额下回和左侧楔叶ReHo值减低,左侧小脑ReHo值升高(P均<0.05)。基于Chinese2020分析获得的相同的差异脑区平均灰质占比[ALFF:(38.85±17.88)%;ReHo:(54.69±13.28)%]高于基于传统脑图谱ICBM152分析[ALFF:(33.75±14.70)%;ReHo:(45.66±12.35)%],但差异无统计学意义(P=0.68、0.21)。结论 基于中国人脑图谱Chinese2020配准的静息态功能磁共振数据分析在检测中国AD患者的局部神经元自发活动方面较传统的西方人脑图谱更准确。  相似文献   
74.
Differences in CYP1A2-mediated metabolisms in human, rat and mouse have been analyzed with Template of human CYP1A2 established in our previous studies (Drug Metab Pharmacokinet 31:363, 2016 and 32:229, 2017). Using more than 25 chemicals including phenanthrene, MeIQx, PhIP, caffeine and furafylline, Template for human CYP1A2 was found to be applicable for rat and mouse CYP1A2 reactions with the consideration of five distinct regional interactions: 1) Expanded use of Ring D region of pro-metabolized molecules and also of trigger molecules, 2) acceptance of secondary amino groups at Position 31 of Ring eC1, 3) overlapping of pro-metabolized and trigger molecules at Ring eC4, 4) restricted maneuvering of substrates into Bay 1 region, and 5) allowance of passage of slightly large ligands in Thin-Area. These distinction points were found to be mutual for both substrates and inhibitors. In the present study, the decision-tree for substrates entering from Thin-Area has been reevaluated in consideration of species differences in human and rodent CYP1A2 forms. As the results, five steps of verification procedures have been introduced to predict the occurrence order of the regioselective metabolisms.  相似文献   
75.
目的探讨自制定位器引导模板辅助技术在正电子发射断层扫描(PET)分子成像定向肺部结节穿刺活检中的应用价值,评估其准确性和安全性。方法收集2018年1月至2018年12月因疑诊为肺癌而需要接受PET分子成像定向肺部结节穿刺活检术的病例60例,采用随机数字表法将研究对象分为观察组(n=30,使用定位器引导模板辅助技术)和对照组(n=30,使用常规徒手操作),比较两组间穿刺针到达预定位置的一次性成功率、穿刺操作时间以及咯血和气胸等并发症的发生率等。结果观察组穿刺针一次性成功率明显高于对照组(86.7%比36.7%,χ^2=15.864,P<0.001);穿刺操作时间明显短于对照组[(21.44±5.75)min比(38.20±8.74)min,t=-8.289,P<0.001];患者并发症发生率明显低于对照组(6.7%比26.7%,χ^2=4.320,P=0.038)。结论自制定位器引导模板辅助技术可使CT实时引导下的PET分子成像定向肺活检术更加精确,缩短操作时间,有效降低并发症发生率,可在临床推广。  相似文献   
76.

Purpose

Guided growth has long been used to treat growth deformities, but the Eight-Plate® system has recently become more widely used by pediatric orthopaedists. Because the current literature lacks evaluation of functional status in the immediate post-operative period, we investigated functional status following use of the Eight-Plate® system.

Methods

We evaluated post-operative delay in return of function following treatment with the Eight-Plate® system at two weeks after surgery. Fifty-one consecutive patients with a growth deformity were treated with the Eight-Plate® system. Patients were comprised of 32 male and 19 female patients with an average age of 11 years (range 2–17.9 years).

Results

Among study participants, 19 patients (37.3 %) had post-operative delay of function. The rate of delayed function for patients 10 years of age or younger and 11 years of age or older was respectively 11.8 and 50 % (P = 0.002). Six of the 19 patients were treated with four or more plates, of which five patients (83.3 %) developed delayed return of function. The rate of delayed function in patients with at least one femoral plate compared to no femoral plate was respectively 45 and 9.1 % (P = 0.006). Bilateral operations were associated with a 66.7 % rate of delayed function compared to 25 % with unilateral operations (P = 0.004). When patients with delay of function were treated with physical therapy, 12 of 13 patients (92.3 %) had complete resolution of their symptoms.

Conclusion

Statistical significance demonstrated that patients at the greatest risk were 11 years of age or older, with four or more plates, with femoral plates, or with bilateral operations. Patients with delayed function were readily corrected by physical therapy.  相似文献   
77.
Multi‐centre data repositories like the Alzheimer's Disease Neuroimaging Initiative (ADNI) offer a unique research platform, but pose questions concerning comparability of results when using a range of imaging protocols and data processing algorithms. The variability is mainly due to the non‐quantitative character of the widely used structural T1‐weighted magnetic resonance (MR) images. Although the stability of the main effect of Alzheimer's disease (AD) on brain structure across platforms and field strength has been addressed in previous studies using multi‐site MR images, there are only sparse empirically‐based recommendations for processing and analysis of pooled multi‐centre structural MR data acquired at different magnetic field strengths (MFS). Aiming to minimise potential systematic bias when using ADNI data we investigate the specific contributions of spatial registration strategies and the impact of MFS on voxel‐based morphometry in AD. We perform a whole‐brain analysis within the framework of Statistical Parametric Mapping, testing for main effects of various diffeomorphic spatial registration strategies, of MFS and their interaction with disease status. Beyond the confirmation of medial temporal lobe volume loss in AD, we detect a significant impact of spatial registration strategy on estimation of AD related atrophy. Additionally, we report a significant effect of MFS on the assessment of brain anatomy (i) in the cerebellum, (ii) the precentral gyrus and (iii) the thalamus bilaterally, showing no interaction with the disease status. We provide empirical evidence in support of pooling data in multi‐centre VBM studies irrespective of disease status or MFS. Hum Brain Mapp 35:1865–1874, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
78.
The aim of our report was to describe the feasibility of robotic retroperitoneal lymph node dissection in the contemporary era. We suggest the linear port location and 90° robotic docking as the main key to minimizing instrument clashing and improving the range of surgical accessibility.  相似文献   
79.
目的探讨3D打印导航模板在儿童寰枢椎脱位治疗中的应用价值。方法选择2015年1月至2019年6月本院收治的16例儿童寰枢椎脱位患者作为研究对象,术前根据寰枢椎CT平扫及三维重建,将数据导入计算机软件后重建寰枢椎模型,设计理想置钉钉道,并结合寰枢椎后方表面骨性结构数据设计出个性化导板。术中使用导板辅助置入寰枢椎椎弓根螺钉。术后评价螺钉位置及治疗效果。结果共置入椎弓根螺钉64枚,寰椎和枢椎分别32枚。寰椎安全性评估系统结果为:0级螺钉28枚,1级螺钉2枚,2级螺钉2枚。枢椎安全性评估系统结果为:0级螺钉30枚,1级螺钉2枚。术中无脊髓、神经根及椎动脉损伤等并发症发生。16例均获得随访,随访时间5~24个月。15例患者在术后3个月后方植骨达到骨性融合; 1例齿状突骨折患者手术中后方未进行植骨,术后5个月复查可见齿状突愈合,于术后1年拆除内固定物。随访期间,所有患者螺钉位置良好,无断钉及松动等情况发生;末次随访,患者颈部疼痛症状缓解,10例存在脊髓受压表现者神经功能均恢复至ASIA分级E级。结论 3D打印导模板可提高儿童寰枢椎置钉的准确性和安全性,减少手术并发症,值得临床推荐。  相似文献   
80.
文题释义:3D 打印手术导板:该导板依据手术需要,通过计算机辅助设计、3D打印制备出的一种具有术中准确定位点、置钉的位置、方向和深度,精确建立孔道、截面、空间距离、相互成角关系及其他复杂空间结构等功能的辅助手术器械,具有获取途径方便、使用方法简单、价格低廉等优点。 颈椎前路椎弓根置钉:是一种区别于传统颈椎后路椎弓根螺钉置钉技术的新型置钉技术,该技术可通过单独前方入路实现颈椎三柱损伤或多节段病变的坚强固定,无需再行后路固定,可有效减少手术创伤和并发症。 背景:下颈椎前路椎弓根螺钉固定技术可通过前方入路实现颈椎坚强固定,具有较大的应用前景。但该技术操作难度大、风险高,目前尚未得到广泛应用。 目的:改良设计一种用于下颈椎双侧前路椎弓根螺钉置钉的3D打印导板,探讨其辅助颈椎前路椎弓根螺钉置钉的可行性及安全性。 方法:选取6具正常成人颈椎标本,男女各3具,行薄层CT扫描后将影像数据以DICOM格式导入Mimics 17.0软件,三维重建后模拟设计出C3-C7双侧颈椎前路椎弓根螺钉钉道导孔,再以颈椎椎体前面、椎体上面前1/2及双侧钩突关节面前1/2骨性结构为标志,反向增厚设计生成导孔基座,形成颈椎前路椎弓根螺钉置钉导板。经3D打印得到导板实体后,在导板辅助下行C3-C7双侧颈椎前路椎弓根螺钉置钉。将置钉后的颈椎标本再次行CT扫描,通过CT断面影像评价置钉准确性。同时利用Mimics17.0软件比较实际钉道与模拟钉道在横断面的内、外偏移角度(α1、α2)差异及其在矢状面的上、下偏移角度(β1、β2)差异。 结果与结论:①双侧共计60枚颈椎前路椎弓根螺钉均顺利置入,其中57枚完全位于椎弓根皮质内,判定为0级,准确率95.0%;另外3枚破出椎弓根皮质,其中1级2枚(3.3%),2级1枚(1.7%);②真实钉道与模拟钉道相比,其横断面内、外偏移角分别为(0.867±0.787)°、(0.783±0.792)°,差异无显著性意义(P > 0.05);矢状面上、下偏移角分别为(1.362±1.380)°、(1.314±1.300)°,差异无显著性意义(P > 0.05)。③提示在设计得到的3D打印导板辅助下可顺利完成下颈椎双侧前路椎弓根螺钉置钉,且具有良好的置钉安全性。 ORCID: 0000-0003-0124-7585(肖强)中国组织工程研究杂志出版内容重点:人工关节;骨植入物;脊柱;骨折;内固定;数字化骨科;组织工程  相似文献   
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