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普伐他汀对大鼠坐骨神经压碎损伤功能恢复的影响

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中国组织工程研究 2025年第5期29卷 942-950页

作者：刘赞安冉李宝成内蒙古科技大学包头医学院内蒙古自治区包头市014000 内蒙古科技大学包头医学院第一附属医院手足踝外科内蒙古自治区包头市014010

背景:普伐他汀是临床上治疗高胆固醇血症的有效药物,目前发现其在中枢神经损伤的治疗上也能发挥有益作用,然而其机制仍未可知。目的:探究普伐他汀治疗能否加速坐骨神经压碎损伤的功能恢复及其潜在作用机制。方法:将雄性SD大鼠随机分为... 详细信息

背景:普伐他汀是临床上治疗高胆固醇血症的有效药物,目前发现其在中枢神经损伤的治疗上也能发挥有益作用,然而其机制仍未可知。目的:探究普伐他汀治疗能否加速坐骨神经压碎损伤的功能恢复及其潜在作用机制。方法:将雄性SD大鼠随机分为假手术组(坐骨神经暴露但不损伤+生理盐水灌胃)、阴性对照组(坐骨神经压碎损伤+生理盐水灌胃)、普伐他汀组(坐骨神经压碎损伤+普伐他汀灌胃)。普伐他汀组大鼠术后普伐他汀(5 mg/kg)灌胃治疗1周,其余两组大鼠给予等量生理盐水灌胃。术后观察各组大鼠一般情况;术后第2,4,6,8周末测量各组大鼠的坐骨功能指数;术后8周末测量腓肠肌湿质量比;EliSA法检测血清中炎症细胞因子的水平;组织形态计量学分析坐骨神经有髓神经纤维数目、纤维直径、轴突直径、髓鞘厚度;RT-qPCR检测神经生长因子、脑源性神经营养因子的mRNA表达量,Western blot法检测生长相关蛋白43的蛋白表达量。结果与结论:与阴性对照组相比,普伐他汀组坐骨神经功能指数恢复更快(P<0.05),更接近于假手术组水平,血清中炎症细胞因子肿瘤坏死因子α及白细胞介素6表达更低(P<0.05)且接近假手术组,坐骨神经中神经生长因子、脑源性神经营养因子的mRNA相对表达量增加(P<0.05或P<0.01),坐骨神经中生长相关蛋白43的蛋白相对表达量也明显增加(P<0.05),有髓神经纤维数目增加更多,纤维直径、轴突直径及髓鞘厚度数值更大(P<0.01)且与假手术组更接近。结果说明,普伐他汀的治疗加速了坐骨神经压碎损伤的功能恢复,其可能机制是抑制炎症细胞因子肿瘤坏死因子α及白细胞介素6的表达及促进神经营养因子神经生长因子、脑源性神经营养因子的分泌。

关键词：周围神经损伤普伐他汀功能恢复神经营养因子坐骨神经功能指数

不同结构的Si_3N_4/BN纤维独石陶瓷的力学性能

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陶瓷 2001年第6期 14-16页

作者：李淑琴黄勇汪长安昝青峰李翠伟清华大学材料科学与工程系新型陶瓷与精细工艺国家重点实验室北京100084

通过实验对两种不同结构在不同温度下的Si3N4/BN纤维独石陶瓷力学性能进行了研究。实验结果表明 :单轴排布的纤维独石陶瓷具有明显的各向异性。 0 0 /90 0 /0 0 排布的纤维独石陶瓷宏观上各向异性不明显。单轴排布的纤维独石陶瓷随温度... 详细信息

通过实验对两种不同结构在不同温度下的Si3N4/BN纤维独石陶瓷力学性能进行了研究。实验结果表明 :单轴排布的纤维独石陶瓷具有明显的各向异性。 0 0 /90 0 /0 0 排布的纤维独石陶瓷宏观上各向异性不明显。单轴排布的纤维独石陶瓷随温度的升高 ,强度下降幅度较小 ,具有优异的高温力学性能。而按 0 0 /90 0 /0 0 排布的纤维独石陶瓷随温度的升高 ,表现为层状结构特征 ,容易开裂。实验通过扫描电镜SEM观察了材料的显微结构以及断口形貌 ,并探索了结构对性能影响的机理。

关键词：氮化硅/氧化硼纤维独石陶瓷力学性能高温各向异性纤维排布角

Adaptive Bistable Stochastic Resonance Based Weak Signal Reception in Additive Laplacian Noise

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China Communications 2024年第1期21卷 228-241页

作者： Jin liu zan li Qiguang Miao li Yang School of Computer Science and Technology Xidian UniversityXi’an 710071China state Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China

Weak signal reception is a very important and challenging problem for communication systems especially in the presence of non-Gaussian noise,and in which case the performance of optimal linear correlated receiver degrades *** at this,a novel uncorrelated reception scheme based on adaptive bistable stochastic resonance(ABSR)for a weak signal in additive Laplacian noise is *** analyzing the key issue that the quantitative cooperative resonance matching relationship between the characteristics of the noisy signal and the nonlinear bistable system,an analytical expression of the bistable system parameters is *** this basis,by means of bistable system parameters self-adaptive adjustment,the counterintuitive stochastic resonance(SR)phenomenon can be easily generated at which the random noise is changed into a benefit to assist signal ***,it is demonstrated that approximately 8dB bit error ratio(BER)performance improvement for the ABSR-based uncorrelated receiver when compared with the traditional uncorrelated receiver at low signal to noise ratio(SNR)conditions varying from-30dB to-5dB.

关键词： adaptive bistable stochastic resonance additive Laplacian noise low signal to noise ratio uncorrelated reception scheme weak signal reception

Numerical simulation of solitary wave propagation based on MPS method

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Acta Oceanologica Sinica 2007年第3期26卷 121-128页

作者： li Shaowu YU Zhi＇ an XIONG zan Department of Port and Coastal Engineering Tianjin University Tianjin 300072 China

The concept of candidate particle set is introduced in the MPS gridless numerical method to generate neighboring particle set ma- trix, which can reduce the CPU time to 1/11 of that before introduction. The Bi-CGSTAB （bi-conjugate gradient stabilized） algorithm is applied to solving the Poisson pressure equation, by which the solving speed is significantly accelerated. The process of solitary waves propagating over a numerical flume and interacting with a vertical wall is simulated. The simulated results of water surface elevation are in good agreement with the analytical solution as well as the measured data. The predicted maximum values of the run-up of solitary waves with various relative incident wave heights agree well with the measured results.

关键词： MPS method candidate particle set Bi-CGSTAB algorithm solitary wave

Epigenetic regulation of the inflammatory response in stroke

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Neural Regeneration Research 2025年第11期20卷 3045-3062页

作者： Jingyi liang Fei Yang Zixiao li Qian li School of Basic Medical Sciences Capital Medical UniversityBeijingChina Department of Neurobiology School of Basic Medical SciencesCapital Medical UniversityBeijingChina Laboratory for Clinical Medicine Beijing Key Laboratory of Neural Regeneration and RepairCapital Medical UniversityBeijingChina Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina National Center for Healthcare Quality Management in Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Chinese Institute for Brain Research BeijingChina Research Unit of Artificial Intelligence in Cerebrovascular Disease Chinese Academy of Medical SciencesBeijingChina Beijing Engineering Research Center of Digital Healthcare for Neurological Diseases BeijingChina Department of Biochemistry and Molecular Biology School of Basic Medical SciencesCapital Medical UniversityBeijingChina Beijing Key Laboratory of Cancer Invasion and Metastasis Research Capital Medical UniversityBeijingChina

Stroke is classified as ischemic or hemorrhagic,and there are few effective treatments for either *** mechanisms play a critical role in secondary brain injury following a stroke,which manifests as cytokine release,blood–brain barrier disruption,neuronal cell death,and ultimately behavioral *** the inflammatory response has been shown to mitigate this cascade of events in experimental stroke ***,in clinical trials of anti-inflammatory agents,longterm immunosuppression has not demonstrated significant clinical benefits for *** may be attributable to the dichotomous roles of inflammation in both tissue injury and repair,as well as the complex pathophysiologic inflammatory processes in *** acute harmful inflammatory responses or inducing a phenotypic shift from a pro-inflammatory to an anti-inflammatory state at specific time points after a stroke are alternative and promising therapeutic *** agents that can modulate inflammation requires a detailed understanding of the inflammatory processes of ***,epigenetic reprogramming plays a crucial role in modulating post-stroke inflammation and can potentially be exploited for stroke *** this review,we summarize current findings on the epigenetic regulation of the inflammatory response in stroke,focusing on key signaling pathways including nuclear factor-kappa B,Janus kinase/signal transducer and activator of transcription,and mitogen-activated protein kinase as well as inflammasome *** also discuss promising molecular targets for stroke *** evidence to date indicates that therapeutic targeting of the epigenetic regulation of inflammation can shift the balance from inflammation-induced tissue injury to repair following stroke,leading to improved post-stroke outcomes.

关键词： DNA methylation histone modification intracerebral hemorrhage ischemic stroke neuroinflammation neuroprotection non-coding RNA RNA methylation subarachnoid hemorrhage treatment

Generation and characterization of orthogonal FH sequences for the cognitive network

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Science China(Information Sciences) 2015年第2期58卷 140-150页

作者： GUAN Lei li zan SI JiangBo HUANG YangChao state Key Laboratory of Integrated Services Networks Xidian University

The existing orthogonal frequency hopping(FH) sequence cannot support the high throughput and high spectrum efficient cognitive FH(CFH) network due to its small family size, high computational complexity and short period. To overcome these disadvantages, this paper investigates the generation of the orthogonal FH sequence and analyzes its multiple accessibility performance based on the CFH frequency division multipleaccess(FDMA) network model. By the random mapping and cyclical shift replacement(CSR) scheme, a large family size of orthogonal FH sequence with dynamic frequency slot number is generated. In this case, the external interference could be eliminated by avoiding the interfered frequencies, and blocking mutual interference incurred for the packet by the orthogonal frequencies. Moreover, the theoretical relationships of the throughput and transmission delay with respect to the user number and the packet arrival rate are given, which shows that our proposed orthogonal FH sequence could support high throughput and short packet transmission delay in CFH-FDMA network. The simulation results validate our theoretical analysis of the CFH-FDMA network performance, and show that our proposed sequence outperforms the widely used no hit zone FH sequences in terms of uniformity, randomness, Hamming correlation, complexity and sensitivity, etc.

关键词： cognitive frequency hopping orthogonal frequency hopping sequence frequency hopping network frequency division multiple access throughput

Method of neural network modulation recognition based on clustering and Polak-Ribiere algorithm

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Journal of Systems Engineering and Electronics 2014年第5期25卷 742-747页

作者： Faquan Yang zan li Hongyan li Haiyan Huang Zhongxian Pan state Key Laboratory of Integrated Service Networks Xidian University School of Electrical and Information Engineering Foshan University

To improve the recognition rate of signal modulation recognition methods based on the clustering algorithm under the low SNR, a modulation recognition method is proposed. The characteristic parameter of the signal is extracted by using a clustering algorithm, the neural network is trained by using the algorithm of variable gradient correction （Polak-Ribiere） so as to enhance the rate of convergence, improve the performance of recognition under the low SNR and realize modulation recognition of the signal based on the modulation system of the constellation diagram. Simulation results show that the recognition rate based on this algorithm is enhanced over 30% compared with the methods that adopt clustering algorithm or neural network based on the back propagation algorithm alone under the low SNR. The recognition rate can reach 90% when the SNR is 4 dB, and the method is easy to be achieved so that it has a broad application prospect in the modulating recognition.

关键词： clustering algorithm feature extraction algorithm of Polak-Ribiere neural network (NN) modulation recognition.

Integrating behavior analysis into architectural modeling

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Frontiers of Computer Science 2015年第1期9卷 15-33页

作者： Luxi CHEN linpeng HUANG Chen li Tao zan Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China Department of Informatics The Graduate University for Advanced Studies Tokyo 108430 Japan

Architectural modeling and behavior analysis are two important concerns in the software development. They are often implemented separately, and specified by their own supporting notations. Architectural modeling helps to guarantee the system design to satisfy the requirement, and behavior analysis can ensure the interaction correctness. To improve the trustworthiness, methods trying to combine architectural modeling and behavior analysis notations together have been proposed, e.g., establishing a one-way mapping relation. However, the one-way relation cannot ensure updating one notation specifications in accordance with the other one, which results in inconsistency problems. In this paper, we present an approach to integrating behavior analysis into architectural modeling, which establishes the interoperability between architectural modeling notation and behavior analysis notation by a bidirectional mapping. The architecture is specified by the modeling language, architecture analysis and design language （AADL）, and then mapped to behavior analysis notation, Darwin/FSP （finite state process） through the bidirectional transformation. The bidirectional transformarion provides traceability, which makes behavior analysis result provided by a model checker can be traced and reflected back to the original AADL specifications. In this way, the behavior analysis is integrated into architectural modeling. The feasibility of our approach is shown by a control system example.

关键词： software architecture component behavior,bidirectional transformation architecture analysis and design language (AADL) model checking

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng li Meifeng Cai Shengjun Miao Yuan li Yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China state Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification