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《Clinical neurophysiology》2019,130(9):1562-1569
ObjectiveConventional deep brain stimulation (DBS) systems with ring-shaped leads generate spherical electrical fields. In contrast, novel directional leads use segmented electrodes. Aim of this study was to quantify the impedance variations over time in subjects with the directional Cartesia-Boston® system.MethodsImpedance records, programming settings, and clinical data of 11 consecutive Parkinsonian patients implanted with DBS directional leads in two Italian centers (Udine and Vicenza) were retrospectively evaluated. Data were collected before starting stimulation (in the operating room and at days 5 and 40) and after switching stimulation on at the successive follow-up visits (1, 6 and 12 months).ResultsDirectional leads have significantly higher impedance than ring leads. Stimulated contacts had always lower impedance compared to non-stimulated contacts. Before DBS-on, all contacts had higher impedance in the operating room, with an initial decrease five days post-surgery and a subsequent increase at day 40, more evident for directional contacts. The impedance of directional leads increased post-implantation at 1 and 6 months with a plateau at 12 months.ConclusionsThere was a significant difference between the directional and ring leads at baseline (before activation of DBS) and during follow-up (chronic DBS).SignificanceOur study reveals new information about the impedance of segmented electrodes that is useful for patient management during the initial test period, as well as during long-term DBS follow-up.  相似文献   
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BackgroundHealth research reporting guidelines for case reports (CARE - CAse REport) published in 2013 and 2017 have become a generally accepted standard for publishing case reports. The CARE guidelines represent an architectural framework for writing an evidence-based case report that can be customized as need for a specialty (or disease) if needed. We aim to develop a CARE guideline extension for acupuncture following the EQUATOR Network (Enhancing the QUAlity and Transparency Of health Research) and the 2010″Guidance for Developers of Health Research Reporting". We have established a group of international experts including; clinicians, researchers and methodologists. We performed a needs assessment based on a review of acupuncture case reports published in the indexed medical literature. The needs assessment will be followed by (1) a series of expert interviews to establish a draft, (2) a modified Delphi process, and (3) a consensus meeting. Following the consensus meeting we will pilot test the CARE draft before publishing the CARE extension for acupuncture.MethodsWe will develop the CARE extensions for acupuncture following recommendations of the EQUATOR Network and the 2010 "Guidance for Developers of Health Research Reporting". We will establish an international multidisciplinary group including clinical practitioners, acupuncturists, researchers of reporting guidelines on acupuncture, clinical epidemiologists and statisticians.We performed a needs assessment, reviewing published case reports using acupuncture as a therapeutic intervention from indexed medical journals (PubMed-PMC and Medline, Scopus, Embase, the Allied and Complementary Medicine Database (AMED), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Wan Fang database, Chinese BioMedicine database (CBM), China National Knowledge Infrastructure (CNKI), and VIP). In consultations with advisors we will develop a draft of potential items to be included in the CARE extension for acupuncture. Then we will conduct a modified Delphi process of at least three rounds, hold a face-to-face consensus meeting, pilot test and submit the CARE extension for acupuncture for publication.ConclusionThe development of a widely accepted CARE extension for acupuncture for case reports published in indexed medical journals. These guidelines will follow the EQUATOR Network recommendations and the 2010 "Guidance for Developers of Health Research Reporting".  相似文献   
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正常生育男性成熟精子mRNA的种类和特征   总被引:1,自引:0,他引:1  
目的:剖析具有正常生育能力男性成熟精子mRNA的种类和丰度。方法:健康并育有后代的成年男性10例,禁欲1周后取精液,上游法优化精子,Trizol试剂提取精子总RNA。混合所有总RNA进行基因表达系列分析(SAGE)。结果:所建SAGE文库共获877个克隆,测序得到21 052个标签,出现两次以上的独特性标签有2 712种。经与SAGEm ap数据库比对,19.7%的独特性标签没有基因匹配,代表新基因;其余能匹配的基因中,67%具有蛋白质结合或核酸结合能力,41%具有催化活性,13%与信号转导有关,与细胞运输、精子结构、转录调节相关者分别达到10%左右。结论:人成熟精子中存在数量庞大、种类繁多的mRNA。  相似文献   
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N(G)-nitro-arginine (NNA) is known to exhibit stereoselective pharmacokinetics in which N(G)-nitro-d-arginine (d-NNA) has a faster clearance rate than N(G)-nitro-l-arginine (l-NNA) in anesthetized rats, and d-NNA undergoes unidirectional chiral inversion. It was postulated that chiral inversion of d-NNA was performed in a two-step pathway by d-amino acid oxidase (DAAO) followed by an unidentified transaminase. Such chiral inversion contributes (at least partially) to the pharmacokinetic stereoselectivity of NNA. This study used the selective inhibitor of DAAO, sodium benzoate, to test the above hypothesis. An i.v. bolus injection of d-NNA (32 mg/kg) and l-NNA (16 mg/kg) in conscious rats exhibited biphasic disposition with different pharmacokinetic parameters in a stereospecific manner (approximately 5-10-fold differences). Unidirectional chiral inversion of d-NNA but not l-NNA was found from these animals. In addition to its similar inhibitory effects on the d-NNA conversion and DAAO activity in kidney homogenates, sodium benzoate completely blocked chiral inversion of d-NNA and led to a smaller stereospecific difference, reflected by a nearly 50% reduction of d-NNA clearance and a 2-fold increase in t(1/2) and area under the curve of d-NNA in benzoate-pretreated rats. The results suggest that DAAO plays an essential role in chiral inversion of d-NNA and chiral inversion contributes mostly to the pharmacokinetic stereospecificity of NNA.  相似文献   
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目的 评价开放复位可塑形钛板内固定治疗跟骨骨折的疗效。方法 对33例(37足)以后关节突移位为主的跟骨骨折,行跟骨外侧入路、开放性复位可塑形钛板螺钉内固定,必要时行植骨术(18例)。结果 平均随访11.5个月,参照Mary—land food score评分,对患足是否疼痛、步态、距下关节及踝关节活动度、是否支架辅助、术后X线摄片等加以评估,19足疗效为优,17足为良,1足可。其中钛板断裂1例,手术切口皮缘坏死1例,换药后自愈。结论 跟骨外侧入路开放复位可塑形钛板螺钉内固定,必要时植骨术是治疗跟骨骨折的有效方法。  相似文献   
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自动移床3D CES MRA在下肢动脉检查中的初步应用   总被引:1,自引:0,他引:1  
目的:探讨自动移床3维增强减影MR血管造影(3DCES MRA)在下肢动脉疾病检查中的应用价值。方法:16例临床怀疑下肢动脉性病变者进行了自动移床3D CES MRA认检查,原始图像经减影后作最大密度投影(MIP)重建。结果:所有病例的血管均显示满意,其中11例可见不同部位和分支动脉狭窄或闭塞,阳性诊断率为68.7%。结论:初步结果表明,自动移床3D CES MRA检查技术对下肢动脉病变有重要诊断价值。  相似文献   
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为了确定可吞服式电子胶囊在人体内的位置,基于矩形永磁体空间磁场解析式,设计了定位系统,提出了相应的定位算法,并进行了实验。系统中两个三轴磁传感器封装在胶囊内,由胶囊和永磁体的空间位姿关系模型,建立了与传感器输出和胶囊位姿变量相关的一组非线性方程。对方程进行了数值求解,并和期望值进行了比较,结果发现该方法是切实可行的。  相似文献   
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目的利用上海交通大学生命质量与机械工程研究所自主开发的冷冻切片处理软件CryoSegmemation提取人体骨骼的边缘,利用逆向工程软件Imageware建立骨骼的面模型,在ANSYS中建立人体腰椎的三维有限元模型。方法利用第三军医大学的第一例男性冷冻切片数据进行图像处理,截面轮廓线信息处理。结果准确快速地建立了完全符合人体解剖特征的腰椎三维有限元模型。结论利用该研究所自主开发的冷冻切片软件和一些现有的商用软件可以准确、快速地建立人体腰椎的三维面模型、体模型及有限元模型,为航空、车辆、船舶、生物医学工程等不同的领域进行数值模拟计算和动力学仿真提供完全符合人体解剖学特征的原始模型。  相似文献   
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