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A biomechanical study of the recovery in spinal stability of flexion/extension and torsion after the resection of different posterior lumbar structures in a sheep model

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A biomechanical study of the recovery in spinal stability of...

A Biomechanical Study on the Recovery in Stability after Different Posterior Lumbar Structure Injury

第二十届全国中西医结合骨伤科学术研讨会、第二届中国医师协会中西医结合医师分会骨伤科学术年会、第十九届浙江省中西医结合骨伤科专业委员会学术年会

作者： Haobo Jia Xinlong Ma Jianxiong Ma shaowen zhu Department of Orthopedics Tianjin Medical University General Hospital Biomechanics labs of Orthopaedics Institute Tianjin Hospital

Posterior lumbar structures are vital for spinal stability,and many researchers thought that laminectomy and facetectomy would lead to severe spinal ***,because living organisms have compensatory repair capacities,their long-term condition after posterior lumbar structure injuries may change over *** study the changes in the lumbar biomechanical stability of flexion/extension and torsion at different time points after the resection of various posterior structures,as well as to assess the capacity for self-healing in lumbar stability,sheep that had undergone laminectomy or facetectomy were used as an experimental animal *** injured sheep models included three groups:laminectomy only,laminectomy plus left total facetectomy,and laminectomy plus bilateral *** sheep that did not undergo a surgical procedure were used as the control *** 0, 6,12,24,36 weeks after the resection of the posterior lumbar structures,the lumbar specimens were harvested for biomechanical testing based on flexion/extension and torsion movements using the Instron 8874 servohydraulic biomechanical testing *** changes in the injured lumbar spine were also analyzed through radiological *** lumbar stability in flexion/extension and torsion was severely decreased after the three types of *** six weeks,the flexion/extension mechanical parameters recovered substantially;each parameter had returned to normal levels by 12 weeks and exceeded the intact group by 24 and 36 *** stiffness also recovered gradually over *** of the injury groups demonstrated decreased intervertebral space and degeneration or even fusion in the small joints of the surgical segment or in adjacent segments based on radiological *** results indicate that the body has the ability to repair the mechanical instability to a certain extent.

关键词： Lumbar posterior structures laminectomy facetectomy stability biomechanics recovery

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A Biomechanical Study on the Recovery in Stability after Dif...

作者： Haobo Jia Xinlong Ma Jianxiong Ma shaowen zhu Department of Orthopedics Tianjin Medical University General Hospital Biomechanics labs of Orthopaedics Institute Tianjin Hospital

Objective:To study the relationship between the extent in the posterior lumbar structures resection and postoperative lumbar stability,the repair responses to the injured and changes in stability at different post-injury time points;To assess the ability and mechanism in self-healing of ***:Small Tail Han sheep were used as experimental *** injury models include 3 groups(each group contains 20 sheep): laminectomy only—Resection of the vertebral plates,supraspinous ligament,interspinous ligament and spinous processes of L4 and L5(Group 1);laminectomy and left L4/5 total facetectomy(Group 2);laminectomy and both L4/5 facetectomies(Group 3).8 complete non-operative sheep were used as the control group(Group of intact).At 0,6,12,24,36 weeks post operation,the lumbar specimens were harvested for spiral CT scan and biomechanical testing and histology *** biomechanical testing,the authors set the range of motion of flexion /extension and bending for each 5°and the range of motion of torsion for each 2.5°.The loading frequency was 0.1 Hz,the loading speed of bending was 2°/s and the loading speed of torsion was 2°/ *** the testing process load—displacement data were *** neutral zone,the neutral zone stiffness and elastic zone stiffness in flexion/extension movement,and stiffness in lateral bending and axial rotation were calculated and compared among specimens in different time points and injury *** changes in injured lumbar spines were analyzed through radiological and pathohistologic *** CT scan was used to evaluate the changes of the vertebral canal diameter,intervertebral height,morphology and scope of scar tissue in laminectomy ***:The sheep' s lumbar stability was destroyed by the 3 types of surgery injuries, especially in flexion/extension and axial rotation(p<0.05).The extent decreases in stability was correlate with the injury severity *** 6 week,the mechanical stabilities of lu

关键词： A Biomechanical Study on the Recovery in Stability after Different Posterior Lumbar Structure Injury

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In掺杂CdO透明导电薄膜的研究

太阳能学报 2018年第3期39卷 769-774页

作者：冯绍文刘少煜祝巍中国科学技术大学物理学院物理实验教学中心

通过磁控射频溅射的方法分别在石英玻璃基底上和硅〈111〉基底上沉积In掺杂CdO透明导电薄膜。利用XRD、紫外可见分光光度计和霍尔效应测量仪测试薄膜的结构、光学和电学性能。一定量的In掺杂可将CdO的光学吸收边从2．2eV提高至3．4eV，... 详细信息

通过磁控射频溅射的方法分别在石英玻璃基底上和硅〈111〉基底上沉积In掺杂CdO透明导电薄膜。利用XRD、紫外可见分光光度计和霍尔效应测量仪测试薄膜的结构、光学和电学性能。一定量的In掺杂可将CdO的光学吸收边从2．2eV提高至3．4eV，甚至更高。同时适量的In掺杂可明显改善CdO薄膜的电学性能，在提高其电子浓度的同时也降低电阻率，获得最低5．8×10-5Ω·cm的电阻率，同时吸收边为3．24eV的透明导电薄膜。In掺杂的CdO薄膜作为一种性能良好的薄膜材料有较好的发展前景。

关键词： CdO薄膜透明导电薄膜磁控射频溅射 XRD 霍尔效应

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碳纳米管及其应用的研究现状

功能材料 2000年第2期31卷 119-120页

作者：朱绍文贾志杰华中师范大学应用物理研究所湖北武汉430079 清华大学机械工程系北京100084

在世界范围内 ,碳纳米管及其应用的研究成为当前材料研究的热点。通过最近数年的研究 ,科技界对于碳纳米管的特性及应用前景有了深刻的认识。目前研究的重点集中在较大批量生产 (公斤级 /日 )和全面应用方面。

关键词：碳纳米管电子器件纳米复合材料

血清校正钙及iPTH对甲状腺全切术后发生甲状旁腺功能减退的预测价值

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中华地方病学杂志 2021年第6期40卷 483-487页

作者：朱少问周立池州市人民医院甲乳血管外科安徽池州247100

目的探讨血清校正钙及全段甲状旁腺激素(iPTH)对甲状腺全切术后发生甲状旁腺功能减退的预测价值。方法采用前瞻性研究,选择2017年6月至2019年6月在池州市人民医院行甲状腺全切术+中央区淋巴结清扫的86例甲状腺乳头状癌患者为观察对象,... 详细信息

目的探讨血清校正钙及全段甲状旁腺激素(iPTH)对甲状腺全切术后发生甲状旁腺功能减退的预测价值。方法采用前瞻性研究,选择2017年6月至2019年6月在池州市人民医院行甲状腺全切术+中央区淋巴结清扫的86例甲状腺乳头状癌患者为观察对象,分析患者术后的甲状旁腺功能减退发生情况及其危险因素;依据术后甲状旁腺功能减退发生情况将患者分为甲状旁腺功能减退组和无甲状旁腺功能减退组,比较两组患者在术前,术后1、3 d及随访期间(术后6个月)血清校正钙及iPTH水平。采用受试者工作特征(ROC)曲线评估患者术后1 d血清校正钙及iPTH水平对甲状腺全切术后发生甲状旁腺功能减退的预测价值。结果在纳入的86例甲状腺乳头状癌患者中,男性17例、女性69例,年龄为(46.3±5.6)岁;术后发生甲状旁腺功能减退者42例,发生率为48.84%;其中,有不同程度的低血钙症状者32例(37.21%),出现永久性甲状旁腺功能减退者2例(2.33%)。logistic回归分析结果显示,腺外侵犯[比值比(OR)=19.28,95%置信区间(CI):2.63~136.81]、双侧中央区淋巴结清扫(OR=1.84,95%CI:1.36~9.13)为甲状腺全切术后发生甲状旁腺功能减退危险因素。在术前、术后6个月,甲状旁腺功能减退组和无甲状旁腺功能减退组患者血清校正钙、iPTH水平比较,差异均无统计学意义(P均>0.05);术后1、3 d,甲状旁腺功能减退组患者血清校正钙及iPTH水平均显著低于无甲状旁腺功能减退组(P均<0.01)。ROC曲线结果显示,血清校正钙的曲线下面积(AUC)=0.724,灵敏度和特异度分别为76.68%、62.14%;iPTH的AUC=0.947,灵敏度和特异度分别为97.68%、92.14%。结论腺外侵犯、双侧中央区淋巴结清扫为甲状腺全切术后发生甲状旁腺功能减退的危险因素,iPTH水平是甲状旁腺功能减退可靠的预测指标。

关键词：甲状旁腺功能减退全段甲状旁腺激素钙预测价值

Exploring HONO formation and its role in driving secondary pollutants formation during winter in the North China Plain

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Journal of Environmental Sciences 2023年第10期132卷 83-97页

作者： Shaobin Zhang Guo Li Nan Ma Yao He shaowen zhu Xihao Pan Wenlin Dong Yanyan Zhang Qingwei Luo Jeannine Ditas Uwe Kuhn Yuxuan Zhang Bin Yuan Zelong Wang Peng Cheng Juan Hong Jiangchuan Tao Wanyun Xu Ye Kuang Qiaoqiao Wang Yele Sun Guangsheng Zhou Yafang Cheng Hang Su Institute for Environmental and Climate Research Jinan UniversityGuangzhou 511443China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Guangzhou 511443China Max Planck Institute for Chemistry Mainz 55128Germany School of Atmospheric Sciences Nanjing UniversityNanjing 210023China Institute of Mass Spectrometry and Atmospheric Environment Jinan UniversityGuangzhou 510632China State Key Laboratory of Severe Weather&Key Laboratory for Atmospheric Chemistry Institute of Atmospheric CompositionChinese Academy of Meteorological SciencesBeijing 100081China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Gucheng Experimental Station of Ecological and Agricultural Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China

Daytime HONO photolysis is an important source of atmospheric hydroxyl radicals(OH).Knowledge of HONO formation chemistry under typical haze conditions,however,is still *** the Multiphase chemistry experiment in Fogs and Aerosols in the North China Plain in 2018,we investigated the wintertime HONO formation and its atmospheric implications at a rural site *** different episodes based on atmospheric aerosol loading levels were classified:clean periods(CPs),moderately polluted periods(MPPs)and severely polluted periods(SPPs).Correlation analysis revealed that HONO formation via *** conversion of NO_(2)was more efficient on aerosol surfaces than on ground,highlighting the important role of aerosols in promoting HONO *** HONO budget analysis indicated a large missing source(with an average production rate of 0.66±0.26,0.97±0.47 and 1.45±0.55 ppbV/hr for CPs,MPPs and SPPs,respectively),which strongly correlated with photo-enhanced reactions(NO_(2)heterogeneous reaction and particulate nitrate photolysis).Average OH formation derived from HONO photolysis reached up to(0.92±0.71),(1.75±1.26)and(1.82±1.47)ppbV/hr in CPs,MPPs and SPPs respectively,much higher than that from O3 photolysis(i.e.,(0.004±0.004),(0.006±0.007)and(0.0035±0.0034)ppbV/hr).Such high OH production rates could markedly regulate the atmospheric oxidation capacity and hence promote the formation of secondary aerosols and pollutants.

关键词： HONO North China Plain Budget analysis OH radicals

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冷弯厚壁钢管短柱试验及规范公式比较

同济大学学报（自然科学版） 2016年第8期44卷 1190-1198页

作者：温东辉沈祖炎李元齐朱少文同济大学土木工程学院上海200092 太原学院建筑工程系山西太原030032 同济大学土木工程防灾国家重点实验室上海200092 武钢集团汉口轧钢厂湖北武汉430035

以宽厚比为主要变化参数,进行了16根冷弯厚壁钢管轴压短柱试验,研究冷弯效应对强度的影响.试验结果表明:荷载-位移曲线的形状主要取决于截面的宽厚比.宽厚比较小时,达到峰值荷载后下降较慢,邻近破坏时构件的轴向位移很大;宽厚比大时,局... 详细信息

以宽厚比为主要变化参数,进行了16根冷弯厚壁钢管轴压短柱试验,研究冷弯效应对强度的影响.试验结果表明:荷载-位移曲线的形状主要取决于截面的宽厚比.宽厚比较小时,达到峰值荷载后下降较慢,邻近破坏时构件的轴向位移很大;宽厚比大时,局部屈曲影响明显,荷载达峰值后下降较快.同时基于试验结果,与国内外规范考虑冷弯效应的屈服强度计算公式进行了比较,认为我国规范考虑冷弯效应的屈服强度计算公式对于全截面有效的冷弯厚壁型钢也是适用的,且偏于保守.

关键词：冷弯厚壁钢管短柱试验冷弯效应规范公式宽厚比

mSOAR评分对急性缺血性卒中患者不良预后风险预测价值的分析

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智慧健康 2022年第11期8卷 37-39页

作者：朱少文英德市人民医院广东英德513000

发生脑卒中是中老年人群的常见和多发的疾病,且具有发病比较高、致残比例高和出现死亡比例高等特点,SOAR(stroke subtype, oxfordshire community stroke project classification, age and prestroke modified rankin, mSOAR)评价得分对于国内发生急性发作的缺血性卒中(acute ischemic stroke,AIS)病人出现的不良预后风险得有着较好的预测价值。在工作中,通过总结分析AIS病人资料有关情况,登记病人年龄、牛津郡社区卒中项目(oxfordshire community stroke project,OCSP)分类别、卒中之前的改进型Rankin统计量表(modified rankin scale,mRS)评分,美国国家卫生研究院关于卒中量表(national Institutes of health stroke scale,NIHSS)评价得分等相关统计计算信息,在入院时以mSOAR统计量表开展评价得分。所有病人在出院时通过mRS工具进行评价得分,在出院时发生的死亡或重残表示为不良预后。mSOAR评价得分预判病人在出院时发生的不良预后等潜在风险的病人工作特点(receiver operating characteristic curve,ROC)的在坐标图中曲线下的所占面积范围(area under curve,AUC)的数值,mSOAR的评价表在预判AIS病人出院时出现不良预后的风险预测水平相对较高。

关键词： m SOAR 急性缺血性卒中不良预后风险预测分析

基于DSP和FPGA的多通道GPS中频信号源设计与实现

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中国测试 2016年第11期42卷 100-106,144页

作者：胡辉杨国艺朱绍文华东交通大学信息工程学院江西南昌330013 哈尔滨工业大学电气工程及自动化学院黑龙江哈尔滨150006

卫星导航信号源是卫星导航接收机研制过程中的重要测试设备。采用软件无线电技术,实现了一种基于DSP+FPGA的多通道GPS中频信号源。基于GPS中频信号数学模型,给出了系统整体设计方案。采用模块化设计,详细阐述了DSP与FPGA的数据交互逻辑... 详细信息

卫星导航信号源是卫星导航接收机研制过程中的重要测试设备。采用软件无线电技术,实现了一种基于DSP+FPGA的多通道GPS中频信号源。基于GPS中频信号数学模型,给出了系统整体设计方案。采用模块化设计,详细阐述了DSP与FPGA的数据交互逻辑、总线接口模块、载波NCO模块、码模块和导航电文缓冲模块等系统关键部分的实现及重要参数设置的依据,并给出Model Sim-Altera 6.4a下各模块的仿真结果。实测结果表明,信号源生成中频信号波形、频谱符合GPS信号体制规范,且能够被软件接收机正确捕获、跟踪。该信号源具有良好的实时性和可扩展性,成本可控,可有效应用于实验室环境下接收机的性能测试。

关键词： GPS信号源多通道数字信号处理器现场可编程门阵列