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骨科计算机辅助术前规划系统

北京生物医学工程 2007年第3期26卷 322-323,296页

作者：薛文东王东风俞超张文强上海交通大学医学院附属第九人民医院骨科上海200011 上海交通大学电子工程系上海200240

为提高假体与股骨腔的匹配,延长人工髋关节假体置换手术植入寿命,本研究基于CT断层影像和反求技术,运用图像处理、真实感图形生成等技术,在计算机中实现可视手术,并可预见和评估手术的结果,从而制定出最优的手术方案。这一系统为提高手... 详细信息

为提高假体与股骨腔的匹配,延长人工髋关节假体置换手术植入寿命,本研究基于CT断层影像和反求技术,运用图像处理、真实感图形生成等技术,在计算机中实现可视手术,并可预见和评估手术的结果,从而制定出最优的手术方案。这一系统为提高手术成功率及延长假体植入的寿命提供了一条新的、精确合理的途径。

关键词：计算机辅助手术配准髋假体

骨质疏松症松质骨连接性参数改变与计算机辅助测量

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中国骨质疏松杂志 2000年第1期6卷 19-22页

作者：戴克戎汤亭亭薛文东吴小涛黄遂柱上海第二医科大学附属第九人民医院骨科 210009

目的　松质骨连接性参数主要指小梁骨的节点数和游离末端数 ,是反映松质骨显微构筑的重要参数 ,而松质骨的构筑情况可直接影响其力学性能。本研究旨在观察骨质疏松症小梁骨连接性参数的改变 ,并介绍一种计算机辅助测量方法。方法　对老... 详细信息

目的　松质骨连接性参数主要指小梁骨的节点数和游离末端数 ,是反映松质骨显微构筑的重要参数 ,而松质骨的构筑情况可直接影响其力学性能。本研究旨在观察骨质疏松症小梁骨连接性参数的改变 ,并介绍一种计算机辅助测量方法。方法　对老年人和青年人股骨头负重区与非负重区、卵巢切除后 7周大鼠椎体骨以及采用重组人生长激素治疗后的椎体标本 ,进行节点数和游离末端数的测量。并发展了小梁骨节点数和游离末端数的计算机图像自动分析系统。即采用 5 μm硬组织切片将其光镜图像输入计算机 ,用我们自行编制的程序进行分析 ,结果与人工计量方法比较 ,具有很好的相关性 (分别为 r=0 .95 ,r=0 .99)。结果　与青年人相比 ,老年人股骨头标本的节点数明显下降 ,游离末端数明显上升(均为 P<0 .0 5 ) ,卵巢切除 3个月后椎体小梁骨的节点数和游离末端数也呈现同样的变化趋势。而重组人生长激素治疗后这些参数有一定的改善 ,其中骨小梁节点数和末治疗组比较 ,其增加有统计学意义( P<0 .0 5 )。结论　骨小梁节点数的下降和游离末端的增加是骨质疏松症的主要病理特征 ,这两个参数的计测对骨质疏松症的诊断、骨折风险预测和药物疗效评定具有较大的参考价值。

关键词：骨质疏松松质骨连接性参数计算机辅助测量

Speciation, sources, and risk assessment of heavy metals in suburban vegetable garden soil in Xianyang City, Northwest China

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Frontiers of Earth Science 2018年第2期12卷 397-407页

作者： Lijun WANG wendong TAO Richard C. SMARDON xue XU Xinwei LU Department of Environmental Science College of Tourism and Environment Shaanxi Normal University Xi'an 710119 China College of Environmental Science and Forestry State University of New York NY 13201 USA

Intensive anthropogenic activities can lead to soil heavy metal contamination resulting in potential risks to the environment and to human health. To reveal the concentrations, speciation, sources, pollution level, and ecological risk of heavy metals in vegetable garden soil, a total of 136 soil samples were collected from three vegetable production fields in the suburbs of Xianyang City, Northwest China. These samples were analyzed by inductively coupled plasma- atomic emission spectrometry and atomic fluorescence spectrometry. The results showed that the mean concentrations of Cd, Co, Cu, Mn, Pb, Zn, and Hg in vegetable garden soil were higher than the corresponding soil element background values of Shaanxi Province. The heavy metals studied in vegetable garden soil were primarily found in the residual fraction, averaging from 31.26% (Pb) to 90.23% (Cr). Considering the non-residual fractions, the mobility or potential risk was in the order of Pb (68.74%)>Co (60.54%)>Mn (59.28%) >Cd (53.54%) ≫Ni (23.36%) >Zn (22.73%)>Cu (14.93%)>V (11.81%)>Cr (9.78%). Cr, Mn, Ni, V, and As in the studied soil were related to soilforming parent materials, while Cu, Hg, Zn, Cd, Co, and Pb were associated with the application of plastic films, fertilizers, and pesticides, as well as traffic emissions and industrial fumes. Cr, Ni, V, and As presented low contamination levels, whereas Co, Cu, Mn, Pb, and Zn levels were moderate, and Cd and Hg were high. Ecological risk was low for Co, Cr, Cu, Mn, Pb, Zn, and As, with high risk observed for Cd and Hg. The overall pollution level and ecological risk of these heavy metals were high.

关键词： heavy metal speciation source pollution level ecological risk vegetable garden soil

Bile acids and metabolic surgery

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Liver Research 2021年第3期5卷 164-170页

作者： Hui xue Luyao Huang Jui Tu Lili Ding wendong Huang Shanghai Key Laboratory of Complex Prescriptions and MOE Key Laboratory for Standardization of Chinese Medicines Institute of Chinese Materia MedicaShanghai University of Traditional Chinese MedicineShanghaiChina Department of Diabetes Complications and Metabolism Institute of Diabetes and Metabolism Research CenterBeckman Research InstituteCity of Hope National Medical CenterDuarteCAUSA

The epidemic of obesity and its co-mortalities has reached an alarming level ***,metabolic surgeries,especially the Roux-en-Y gastric bypass and vertical sleeve gastrectomy,are the most effective and sustainable treatments for obesity,type 2 diabetes,non-alcoholic steatohepatitis,as well as other metabolic ***,the invasive nature of the surgeries limits their broad ap-plications to the general ***,developing alternative non-invasive approaches to mimic metabolic surgery is an important direction of the *** studies have identified several potential metabolic surgery-induced downstream endocrine mediators,among which bile acids are key candidate signaling *** acids are profoundly altered by metabolic surgery,which contributes to the metabolic effects of the *** this review,we focus on the most recent studies on the roles of bile acids and bile acid receptors farnesoid X receptor and Takeda G protein-coupled receptor 5 in mediating the metabolic effects of metabolic *** conclude that targeting bile acid pathways may be a promising pharmacological approach to mimic the beneficial effects of metabolic surgery.

关键词： Metabolic surgery Obesity Type 2 diabetes(T2D) Non-alcoholic fatty liver disease(NAFLD) Bile acid Farnesoid X receptor(FXR) Takeda G protein-coupled receptor 5(TGR5)

Design and implementation of a jellyfish otolith-inspired MEMS vector hydrophone for low-frequency detection

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Microsystems & Nanoengineering 2021年第1期7卷 41-50页

作者： Renxin Wang Wei Shen Wenjun Zhang Jinlong Song Nansong Li Mengran Liu Guojun Zhang Chenyang xue wendong Zhang State Key Laboratory of Dynamic Testing Technology North University of ChinaTaiyuanChina College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbinChina Hubei Key Laboratory of Modern Manufacturing Quantity Engineering School of Mechanical EngineeringHubei University of TechnologyWuhanHubeiChina

Detecting low-frequency underwater acoustic signals can be a challenge for marine *** by the notably strong response of the auditory organs of pectis jellyfish to ultralow frequencies,a kind of otolith-inspired vector hydrophone(OVH)is developed,enabled by hollow buoyant spheres atop *** parametric analysis is performed to optimize the cilium structure in order to balance the resonance frequency and *** the structural parameters of the OVH are determined,the stress distributions of various vector hydrophones are simulated and *** shock resistance of the OVH is also ***,the OVH is fabricated and *** receiving sensitivity of the OVH is measured to be as high as−202.1 dB@100 Hz(0 dB@1 V/μPa),and the average equivalent pressure sensitivity over the frequency range of interest of the OVH reaches−173.8 dB when the frequency ranges from 20 to 200 *** 3 dB polar width of the directivity pattern for the OVH is measured as 87°.Moreover,the OVH is demonstrated to operate under 10 MPa hydrostatic *** results show that the OVH is promising in low-frequency underwater acoustic detection.

关键词： underwater spheres hydrostatic

Piezoresistive properties of resonant tunneling diodes

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Frontiers of Electrical and Electronic Engineering in China 2007年第4期2卷 449-453页

作者： MAO Haiyang XIONG Jijun ZHANG wendong xue Chenyang SANG Shengbo BAO Aida Key Laboratory of Instrumentation Science and Dynamic Measurement of the Ministry of Education Key Laboratory of the Electronic Measurement Technology of the National DefenseNorth University of ChinaTaiyuan 030051China

measurement system was designed and established to test the piezoresistive properties of resonant tunneling diodes(RTDs).The current-voltage characteristic shifts of RTD at different stress states were *** experimental results demonstrate that the piezoresistive sensitivity of RTD is larger than 1x10−8 Pa−*** accurately represent the piezoresistive properties of RTD,the current-voltage characteristic coherence of the same RTD was *** to the experimental results,the largest relative resistance shift of an RTD in the same measurement environment is less than 3%,of which 1%is caused by the testing apparatuses.

关键词： RTD piezoresistive property coherence sensitivity Raman

Synaptic development in the injured spinal cord cavity following co-transplantation of fetal spinal cord cells and autologous activated Schwann cells

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Neural Regeneration Research 2010年第19期5卷 1445-1450页

作者： wendong Ruan Yuan xue Ninghua Li Xiaotao Zhao Huajian Zhao Peng Li Department of Orthopedics Tianjin Medical University Genemal Hospital Tianjin 300052 China Beijing Hospital Ministry of Health Beijing 100730 China

Transplantation of activated transgenic Schwann cells or a fetal spinal cord cell suspension has been widely used to treat spinal cord injury. However, little is known regarding the effects of co-transplantation. In the present study, autologous Schwann cells in combination with a fetal spinal cord cell suspension were transplanted into adult Wistar rats with spinal cord injury, and newly generated axonal connections were observed ultrastructurally. Transmission electron microscopic observations showed that the neuroblast first presented cytoplasmic processes, followed by pre- and postsynaptic membranes with low electron density forming a dense projection. The number and types of synaptic vesicles were increased. Synaptic connections developed from single cell body-dendritic synapses into multiple cell body-dendritic and dendrite-dendritic synapses. In addition, the cell organs of the transplanted neuroblast, oligodendroblast and astroblast matured gradually. The blood-brain barrier appeared subsequently. Moreover, neurofilament, histamine, calcitonin-gene-related peptides, and glial fibrillary acidic protein positive fibers were observed in the transplant region. These findings demonstrate that fetal spinal cord cells in the presence of autologous activated Schwann cells can develop into mature synapses in the cavity of injured spinal cords, suggesting the possibility of information exchange through the reconstructed synapse between fetal spinal cord cells and the host.

关键词： fetal spinal cord cell suspension synapse development autologous activated Schwann cells spinal cord injury peripheral nerve injury neural regeneration

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基于CMUT环形阵列的反射超声成像方法

微纳电子技术 2024年第1期61卷 137-143页

作者：秦祚敏薛铮刘书睿张国军杨玉华张文栋何常德中北大学省部共建动态测试技术国家重点实验室太原030051 北京宇航系统工程研究所北京100076

电容式微机械超声换能器(CMUT)具有频带宽、制造成本低、易与电路集成等优点,在医学成像领域具有广阔的应用前景。CMUT高密度阵元、低制造成本的特点使其拥有制备超声环形阵列独特的优势。基于CMUT环形阵列提出了反射式超声成像算法,采... 详细信息

电容式微机械超声换能器(CMUT)具有频带宽、制造成本低、易与电路集成等优点,在医学成像领域具有广阔的应用前景。CMUT高密度阵元、低制造成本的特点使其拥有制备超声环形阵列独特的优势。基于CMUT环形阵列提出了反射式超声成像算法,采用k-Wave工具箱搭建模型进行仿真实验,验证了算法的可行性。搭建了基于32阵元CMUT环形阵列的超声成像验证平台,通过旋转实现稀疏阵元的反射式超声成像。图像重建结果表明,该反射成像算法可实现目标体重建,目标体直径测试值为6.14 cm,与目标体直径实际值6.00 cm相比,成像误差为2.33%,验证了CMUT环形阵列在超声成像中应用的可行性。该研究为进一步研制基于高密度CMUT换能器的超声成像系统提供了参考。

关键词：电容式微机械超声换能器(CMUT) 环形阵列反射超声成像医学成像

Spatial Distribution of Mature Larvae of Obolodiplosis robiniae and Damage Regularity of Its First Generation Larvae on Leaves of Locust( Robinia pseudoacacia)

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Plant Diseases and Pests 2013年第4期4卷 39-41页

作者： Sun Jingshuang Cao Ning Tian wendong Qu Haixue xue Xinhua Tian Guihong Fangshan Forest and Fruit Trees Technology Service Center

[ Objective] The paper was to explore the population dynamics of Obolodiplosis robiniae （Haldemarm）. [ Method ] The spatial distribution of mature larvae of O. robiniae and the damage regularity of its first generation larvae on leaves of locust were studied in Fangshan District of Beijing City. [ Result] The spa- tial distribution of mature larvae of O. robin/ae in the forest was sigrrificanfly higher than those in forest edge and periphery of forest edge. The attack of the first generation larvae was mainly concentrated in the lower part of tree crown. [ Conclusion] The study provides theoretical basis for the effective control against O. robiniae.

关键词： Obolodiplosis robiniae Mature larvae Spatial distribution Damage regularity