维普中文期刊产品整合服务
144篇 您的检索式:关键字=BACK
    题名 作者 年代 出处 被引量
1Pathophysiology, diagnosis, and treatment of discogenic low back pain显示文摘Discogenic low back pain is a serious medical and social problem, and accounts for 26%-42% of the patients with chronic low back pain. Recent studies found that the pathologic features of discs obtained from the patients with discogenic low back pain were the formation of the zones of vascularized granulation tissue, with extensive innervation in fissures extending from the outer part of the annulus into the nucleus pulposus. Studies suggested that the degeneration of the painful disc might originate from the injury and subsequent repair of annulus fibrosus. Growth factors such as basic fibroblast growth factor, transforming growth factor β1, and connective tissue growth factor, macrophages and mast cells might play a key role in the repair of the injured annulus fibrosus and subsequent disc degeneration. Although there exist controversies about the role of discography as a diagnostic test, provocation discography still is the only available means by which to identify a painful disc. A recent study has classified discogenic low back pain into two types that were annular disruption-induced low back pain and internal endplate disruption-induced low back pain, which have been fully supported by clinical and theoretical bases. Current treatment options for discogenic back pain range from medicinal anti-inflammation strategy to invasive procedures including spine fusion and recently spinal arthroplasty. However, these treatments are limited to relieving symptoms, with no attempt to restore the disc's structure. Recently, there has been a growing interest in developing strategies that aim to repair or regenerate the degenerated disc biologically.Bao-Gan Peng 2013World Journal of Orthopedics2013,4,2:40
2Measures against the adverse impact of natural wind on air-cooled condensers in power plant显示文摘The natural wind plays disadvantageous roles in the operation of air-cooled steam condensers in power plant.It is of use to take various measures against the adverse effect of wind for the performance improvement of air-cooled condensers.Based on representative 2×600 MW direct air-cooled power plant,three ways that can arrange and optimize the flow field of cooling air thus enhance the heat transfer of air-cooled condensers were proposed.The physical and mathematical models of air-cooled condensers with various flow leading measures were presented and the flow and temperature fields of cooling air were obtained by CFD simulation.The back pressures of turbine were calculated for different measures on the basis of the heat transfer model of air-cooled condensers.The results show that the performance of air-cooled condensers is improved thus the back pressure of turbine is lowered to some extent by taking measures against the adverse impact of natural wind.YANG LiJun,DU XiaoZe & YANG YongPing Key Laboratory of Condition Monitoring and Control for Power Plant Equipment of Ministry of Education of China,North China Electric Power University,Beijing 102206,China 2010Science China(Technological Sciences)2010,53,5:21
3Teach back模式在重症肺炎患者健康宣教中的应用及对心理韧性、自我效能和生活质量的影响显示文摘目的:研究Teach back模式在重症肺炎患者健康宣教中的应用及对心理韧性、自我效能和生活质量的影响。方法:选取2016年11月—2017年9月滨州医学院烟台附属医院收治的44例重症肺炎患者纳入对照组,采用常规健康宣教;选取2017年11月—2018年9月我院收治的44例重症肺炎患者纳入研究组,采用Teach back模式健康宣教。比较两组患者心理韧性量表、一般自我效能量表、生活质量量表(SF-36)得分情况,肺功能[1s用力呼气容积(FEV 1)、用力肺活量(FVC)]水平。结果:干预3个月后,研究组心理韧性量表、一般自我效能量表、SF-36评分及肺功能(FEV 1、FVC)水平高于对照组,差异均有统计学意义(P<0.05)。结论:Teach back模式在重症肺炎患者健康宣教中的应用效果良好,能够提升患者心理韧性、自我效能及生活质量,改善肺功能并降低复发率。周青华 2020中华现代护理杂志2020,26,24:19
4Teach back宣教模式在老年代谢综合征患者健康素养教育中的应用显示文摘目的探讨Teach back宣教模式在老年代谢综合征患者健康素养教育中的应用效果。方法选择2015年10月至2017年9月收治的老年代谢综合征患者110例为研究对象,采用随机数字表法分为观察组与对照组各55例。对照组给予常规健康教育,观察组给予Teach back宣教模式。随访6个月,采用《慢性病病人健康素养调查量表》测评2组患者干预前后健康素养水平,比较2组患者干预前后收缩压(SBP)、舒张压(DBP)、体质量指数(BMI)、腰围(wc)、空腹血糖(FPG)、糖化血红蛋白(HbAlc)、三酰甘油(TG)、总胆固醇(Tc)水平。结果随访6个月,剔除失访或退出病例,观察组、对照组分别有52、49例完成本研究。观察组信息获取能力、交流互动能力、改善健康意愿、经济支持意愿评分分别为(27.18±4.15)、(29.63±4.56)、(14.63±2.07)、(7.85±1.23)分,均明显高于对照组的(23.96±3.83)、(26.34±3.87)、(13.04±1.56)、(6.91±0.93)分,差异有统计学意义(t=3.898—4.339,均P<0.05);随访6个月,观察组疾病知识知晓率、健康行为依从率分别为92.31%(48/52)、86.54%(45/52),均明显高于对照组的69.39%(34/49)、63.27%(31/49),差异有统计学意义(x^2=8.677、7.336,均P<0.01);随访6个月,观察组SBP、DBP、BMI、WC分别为(135.73±8.53)mmHg(1mmHg=0.133kPa)、(85.69±8.74)mmHg、(23.76±1.91)kg/m^2、(87.13±6.45)cm,均明显高于对照组的(141.79±7.24)mmHg、(89.45±8.37)mmHg、(24.98±2.03)kg/m^2、(90.13±6.74)cm,差异有统计学意义0=2.206—3.831,均P<0.05);观察组FPG、HbA1c、TG、TC分别为(6.57±0.91)mmol/L、(5.85±1.03)%、(1.71±0.68)mmol/L、(4.67±0.68)mmol/L,均明显低于对照组的(7.24±1.03)mmol/L、(6.46±1.14)%、(1.98±O.63)mmol/L、(4.98±0.72)mmol/L,差异有统计学意义(t=2.067~3.469,均P<0.05)。结论Teachback宣教模式可明显提高老年代谢综合征患者的健康素养水平,改善体质指标及代谢指标,对防治各种慢性病、改善生命质量具有重要意义。金璐 2018中国实用护理杂志2018,34,34:16
5基于人工神经网络的百度地图坐标解密方法显示文摘提出了一种针对百度地图坐标加密算法的解密方法,利用百度开放的坐标转换接口获取多组GPS和百度地图坐标对,基于BP神经网络拟合出逆转换函数,利用训练后的BP网络来预测新的百度坐标所对应的GPS坐标。实验结果证明,该方法得到的GPS坐标与实际的GPS坐标较为接近,因而可以达到较为理想的解密结果。潘伟洲 陈振洲 李兴民 2014计算机工程与应用2014,50,17:13
6Wind power prediction based on variational mode decomposition multi-frequency combinations显示文摘Because of the uncertainty and randomness of wind speed, wind power has characteristics such as nonlinearity and multiple frequencies. Accurate prediction of wind power is one effective means of improving wind power integration. Because the traditional single model cannot fully characterize the fluctuating characteristics of wind power, scholars have attempted to build other prediction models based on empirical mode decomposition(EMD) or ensemble empirical mode decomposition(EEMD) to tackle this problem. However, the prediction accuracy of these models is affected by modal aliasing and illusive components. Aimed at these defects, this paper proposes a multi-frequency combination prediction model based on variational mode decomposition(VMD). We use a back propagation neural network(BPNN),autoregressive moving average(ARMA)model, and least square support vector machine(LS-SVM) to predict high, intermediate,and low frequency components,respectively. Based on the predicted values of each component, the BPNN is applied to combine them into a final wind power prediction value.Finally,the prediction performance of the single prediction models(ARMA,BPNN and LS-SVM)and the decomposition prediction models(EMD and EEMD) are used to compare with the proposed VMD model according to the evaluation indices such as average absolute error, mean square error,and root mean square error to validate its feasibility and accuracy. The results show that the prediction accuracy of the proposed VMD model is higher.Gang ZHANG Hongchi LIU Jiangbin ZHANG Ye YAN Lei ZHANG Chen WU Xia HUA Yongqing WANG 2019Journal of Modern Power Systems and Clean Energy2019,7,2:10
7Management of lumbar zygapophysial (facet) joint pain显示文摘AIM: To investigate the diagnostic validity and therapeutic value of lumbar facet joint interventions in managing chronic low back pain.METHODS: The review process applied systematic evidence-based assessment methodology of controlled trials of diagnostic validity and randomized controlled trials of therapeutic efficacy. Inclusion criteria encompassed all facet joint interventions performed in a controlled fashion. The pain relief of greater than 50% was the outcome measure for diagnostic accuracy assessment of the controlled studies with ability to perform previously painful movements, whereas, for randomized controlled therapeutic efficacy studies, the primary outcome was significant pain relief and the secondary outcome was a positive change in functional status. For the inclusion of the diagnostic controlled studies, all studies must have utilized either placebo controlled facet joint blocks or comparative local anesthetic blocks. In assessing therapeutic interventions, short-term and long-term reliefs were defined as either up to 6 mo or greater than 6 mo of relief. The literature search was extensive utilizing various types of electronic search media including Pub Med from 1966 onwards, Cochrane library, National Guideline Clearinghouse, clinicaltrials.gov, along with other sources includingprevious systematic reviews, non-indexed journals, and abstracts until March 2015. Each manuscript included in the assessment was assessed for methodologic quality or risk of bias assessment utilizing the Quality Appraisal of Reliability Studies checklist for diagnostic interventions, and Cochrane review criteria and the Interventional Pain Management Techniques- Quality Appraisal of Reliability and Risk of Bias Assessment tool for therapeutic interventions. Evidence based on the review of the systematic assessment of controlled studies was graded utilizing a modified schema of qualitative evidence with best evidence synthesis, variable from level Ⅰ to level Ⅴ.RESULTS: Across all databases, 16 high quality diagnostic accuracy studies were identified. In addition, multiple studies assessed the influence of multiple factors on diagnostic validity. In contrast to diagnostic validity studies, therapeutic efficacy trials were limited to a total of 14 randomized controlled trials, assessing the efficacy of intraarticular injections, facet or zygapophysial joint nerve blocks, and radiofrequency neurotomy of the innervation of the facet joints. The evidence for the diagnostic validity of lumbar facet joint nerve blocks with at least 75% pain relief with ability to perform previously painful movements was level Ⅰ, based on a range of level Ⅰ to Ⅴ derived from a best evidence synthesis. For therapeutic interventions, the evidence was variable from level Ⅱ to Ⅲ, with level Ⅱ evidence for lumbar facet joint nerve blocks and radiofrequency neurotomy for long-term improvement(greater than 6 mo), and level Ⅲ evidence for lumbosacral zygapophysial joint injections for short-term improvement only.CONCLUSION: This review provides significant evidence for the diagnostic validity of facet joint nerve blocks, and moderate evidence for therapeutic radiofrequency neurotomy and therapeutic facet joint nerve blocks in managing chronic low back pain.Laxmaiah Manchikanti Joshua A Hirsch Frank JE Falco Mark V Boswell 2016World Journal of Orthopedics2016,7,5:9
8Long-term deformation analysis of Shuibuya concrete face rockfill dam based on response surface method and improved genetic algorithm显示文摘Due to the size effects of rockfill materials, the settlement difference between numerical simulation and in situ monitoring of rockfill dams is a topic of general concern.The constitutive model parameters obtained from laboratory triaxial tests often underestimate the deformation of high rockfill dams.Therefore, constitutive model parameters obtained by back analysis were used to calculate and predict the long-term deformation of rockfill dams.Instead of using artificial neural networks (ANNs), the response surface method (RSM) was employed to replace the finite element simulation used in the optimization iteration.Only 27 training samples were required for RSM, improving computational efficiency compared with ANN, which required 300 training samples.RSM can be used to describe the relationship between the constitutive model parameters and dam settlements.The inversion results of the Shuibuya concrete face rockfill dam (CFRD) show that the calculated settlements agree with the measured data, indicating the accuracy and efficiency of RSM.Fu-hai Yao Shao-heng Guan He Yang Yuan Chen Huan-feng Qiu Gang Ma Qi-wen Liu 2019Water Science and Engineering2019,12,3:9
9Back analysis of mechanical parameters of roller compacted concrete dam显示文摘In view of the diversity and complexity of mechanical parameters of roller compacted concrete dam(RCCD),the uniform design method,partial least-squares regression(PLS)and least squares support vector machine(LSSVM)were applied to the back analysis of RCCD with the use of the complex nonlinear relationship between dam mechanical parameters and dam displacements.During the process of back analysis,the initial samples of parameters were designed with uniform design method.Then,a transversely isotropic model of RCCD was established by MSC.Marc software.Through this model,training samples of LSSVM model could be obtained.And then,the complex nonlinear relationship between relative values of hydraulic components of dam displacements and mechanical parameters was established.Finally,actual relative values of dam hydraulic components are isolated from the measured data of dam displacements by using PLS.By inputting the isolated relative values into LSSVM model,the back analysis values of RCCD mechanical parameters can be obtained.The example analysis showed that mechanical parameters obtained by the above-mentioned back analysis method are reasonable,and the back analysis method is feasible.GU ChongShi 1,2,3,LI Bo 1,XU GuangLei 4 &YU Hong 1,2,3 1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China 2College of Water Conservancy Hydropower,Hohai University,Nanjing 210098,China 3National Engineering Research Center of Water Resources Engineering Safety,Efficient Utilization and Nanjing 210098,China 4 Nanjing Hydraulic Research Institute,Nanjing 210029,China 2010Science China(Technological Sciences)2010,53,3:8
10Genetic Algorithm Based on New Evaluation Function and Mutation Model for Training of BPNN显示文摘A local minimum is frequently encountered in the training of back propagation neural networks (BPNN), which sharply slows the training process. In this paper, an analysis of the formation of local minima is presented, and an improved genetic algorithm (GA) is introduced to overcome local minima. The Sigmoid function is generally used as the activation function of BPNN nodes. It is the flat characteristic of the Sigmoid function that results in the formation of local minima. In the improved GA, pertinent modifications are made to the evaluation function and the mutation model. The evaluation of the solution is associated with both the training error and gradient. The sensitivity of the error function to network parameters is used to form a self adapting mutation model. An example of industrial application shows the advantage of the improved GA to overcome local minima.周祥 何小荣 陈丙珍 2002Tsinghua Science and Technology2002,7,1:8
11DDoS Attack Detection Scheme Based on Entropy and PSO-BP Neural Network in SDN显示文摘SDN (Software Defined Network) has many security problems, and DDoS attack is undoubtedly the most serious harm to SDN architecture network. How to accurately and effectively detect DDoS attacks has always been a difficult point and focus of SDN security research. Based on the characteristics of SDN, a DDoS attack detection method combining generalized entropy and PSOBP neural network is proposed. The traffic is pre-detected by the generalized entropy method deployed on the switch, and the detection result is divided into normal and abnormal. Locate the switch that issued the abnormal alarm. The controller uses the PSO-BP neural network to detect whether a DDoS attack occurs by further extracting the flow features of the abnormal switch. Experiments show that compared with other methods, the detection accurate rate is guaranteed while the CPU load of the controller is reduced, and the detection capability is better.Zhenpeng Liu Yupeng He Wensheng Wang Bin Zhang 2019China Communications2019,16,7:8
12Insights of stem cell-based endogenous repair of intervertebral disc degeneration显示文摘Low back pain has become more prevalent in recent years,causing enormous economic burden for society and government.Common therapies used in clinics including conservative treatment and surgery can only relieve pain.Subsequent cell-based treatment such as mesenchymal stem cell transplantation poses problems such as short duration of therapeutic effect and tumorigenesis.Recently,the discovery and identification of stem cell niche and stem/progenitor cells in intervertebral disc bring increased attention to endogenous repair strategy.Therefore,we review the studies involving endogenous repair strategy and present the characteristics and current status of this treatment.Meanwhile,we also discuss the strategy and perspective of endogenous repair strategy in future.Yang Liu Yan Li Li-Ping Nan Feng Wang Shi-Feng Zhou Xin-Min Feng Hao Liu Liang Zhang 2020World Journal of Stem Cells2020,12,4:7
13Modeling hot deformation behavior of low-cost Ti-2Al-9.2Mo-2Fe beta titanium alloy using a deep neural network显示文摘Ti-2 Al-9.2 Mo-2 Fe is a low-cost β titanium alloy with well-balanced strength and ductility, but hot working of this alloy is complex and unfamiliar. Understanding the nonlinear relationships among the strain,strain rate, temperature, and flow stress of this alloy is essential to optimize the hot working process.In this study, a deep neural network(DNN) model was developed to correlate flow stress with a wide range of strains(0.025–0.6), strain rates(0.01–10 s^-1) and temperatures(750–1000℃). The model, which was tested with 96 unseen datasets, showed better performance than existing models, with a correlation coefficient of 0.999. The processing map constructed using the DNN model was effective in predicting the microstructural evolution of the alloy. Moreover, it led to the optimization of hot-working conditions to avoid the formation of brittle precipitates(temperatures of 820–1000℃ and strain rates of 0.01-0.1 s^-1).Cheng-Lin Li P.L.Narayana N.S.Reddy Seong-Woo Choi Jong-Taek Yeom Jae-Keun Hong Chan Hee Park 2019Journal of Materials Science & Technology2019,35,5:7
14Slope reliability and back analysis of failure with geotechnical parameters estimated using Bayesian inference显示文摘A Bayesian approach is proposed for the inference of the geotechnical parameters used in slope design.The methodology involves the construction of posterior probability distributions that combine prior information on the parameter values with typical data from laboratory tests and site investigations used in design.The posterior distributions are often complex,multidimensional functions whose analysis requires the use of Markov chain Monte Carlo(MCMC)methods.These procedures are used to draw representative samples of the parameters investigated,providing information on their best estimate values,variability and correlations.The paper describes the methodology to define the posterior distributions of the input parameters for slope design and the use of these results for evaluation of the reliability of a slope with the first order reliability method(FORM).The reliability analysis corresponds to a forward stability analysis of the slope where the factor of safety(FS)is calculated with a surrogate model from the more likely values of the input parameters.The Bayesian model is also used to update the estimation of the input parameters based on the back analysis of slope failure.In this case,the condition FS?1 is treated as a data point that is compared with the model prediction of FS.The analysis requires a sufficient number of observations of failure to outbalance the effect of the initial input parameters.The parameters are updated according to their uncertainty,which is determined by the amount of data supporting them.The methodology is illustrated with an example of a rock slope characterised with a Hoek-Brown rock mass strength.The example is used to highlight the advantages of using Bayesian methods for the slope reliability analysis and to show the effects of data support on the results of the updating process from back analysis of failure.Luis-Fernando Contreras Edwin T.Brown 2019Journal of Rock Mechanics and Geotechnical Engineering2019,11,3:7
15CCD视频信号处理电路设计显示文摘针对e2v公司的CCD67 Back Illuminated NIMO型CCD,设计其视频信号处理电路,包括:前置放大电路、相关双采样(CDS)电路以及低通滤波电路等。实验结果表明,设计的CCD视频信号处理电路能够达到去除噪声、提取有用信号的目的。程鹏飞 顾明剑 王模昌 2006科学技术与工程2006,6,24:7
16A Method for the Environmental Quality Assessment of Surface Water Based on Artificial Neural NetworksYANG Guo\|dong\+1,\ PAN Da\|feng\+2,\ FAN Ying\|fang\+3 1.Dep. of Environmental Science, Shanxi Uni., Taiyuan 030006, China 2.Shanxi Academy of Agriculture Science, Taiyuan 030031, China 3.Institute of Molecular Science, Shanxi Uni., Taiyuan 030006, C 2000Systems Science and Systems Engineering2000,10,1:7
17Soft Fault Diagnosis for Analog Circuits Based on Slope Fault Feature and BP Neural Networks显示文摘Fault diagnosis is very important for development and maintenance of safe and reliable electronic circuits and systems. This paper describes an approach of soft fault diagnosis for analog circuits based on slope fault feature and back propagation neural networks (BPNN). The reported approach uses the voltage relation function between two nodes as fault features; and for linear analog circuits, the voltage relation function is a linear function, thus the slope is invariant as fault feature. Therefore, a unified fault feature for both hard fault (open or short fault) and soft fault (parametric fault) is extracted. Unlike other NN-based diagnosis methods which utilize node voltages or frequency response as fault features, the reported BPNN is trained by the extracted feature vectors, the slope features are calculated by just simulating once for each component, and the trained BPNN can achieve all the soft faults diagnosis of the component. Experiments show that our approach is promising.胡梅 王红 胡庚 杨士元 2007Tsinghua Science and Technology2007,12,S1:6
18网络攻防课程建设经验探讨显示文摘分析网络攻防课程在教学知识体系设置、教材选择、实验组织等方面的问题,以济南大学网络工程专业'网络攻防'课程的教学实际为例,从教学结构的设置与改进、教学参考资料的选取、课程实验改进以及教学评价模式等方面阐述'网络攻防'教学的具体措施,介绍阐述了6年教学实践过程中采取的3次教学大纲的修订经验、3次教学内容的改进措施以及3次实验内容的改革方法,提出以赛促教、以赛促学、赛教结合的教学观点。贾忠田 刘悦 张波 2019计算机教育2019,,3:6
19日本冷库考察记实显示文摘2008年8月在日本进行了对冷库建设、管理等方面的实地考察;与日本冷藏库协会、流通行业协会等机构围绕着冷库建设,进行了技术交流;到前川制作所参观 CO2NEW-TON3000新型制冷机组的生产等。谈向东 2008冷藏技术2008,31,4:4
20Provenance and tectonic setting transition as recorded in the Neoproterozoic strata, western Jiangnan Orogen:Implications for South China within Rodinia显示文摘The Neoproterozoic Tonian strata (ca.870-725 Ma) in the western Jiangnan Orogen archive the records of sedimentary provenance and tectonic setting which can be used to understand the geological evolution of the South China Continent.These strata are separated into the basement and cover sequences by a regional angular unconformity.The basement sequence can be subdivided into the lower and the upper parts by the widespread interbedded ca.840 Ma basalt with pillow structure.In the present work,234 concordant detrital zircon analyses are obtained from three Tonian sandstone samples in the Fanjingshan district,Guizhou Province.Combined with previous results,a total of 1736 analyses of detrital zircon U-Pb ages derived from 12 formations of Tonian strata in the western Jiangnan Orogen are used to decipher the integrated sedimentary and tectonic histories.The zircons from the lowermost part of the basement sequence (the Yujiagou Formation) show oval morphology and display two Paleoproterozoic age peaks at 2325 Ma and 1845 Ma which are similar with the detrital zircon age peaks from the Late Paleoproterozoic to Early Mesoproterozoic Dongchuan/Dahongshan/Hekou groups,suggesting a passive margin basin in which the sediments were mainly sourced from the southwestern Yangtze Block.However,the zircon age population of the lower part of the basement sequence (the Xiaojiahe,Huixiangping formations and their equivalents) indicates the sedimentary derivation from bidirectional sources (the ca.870 Ma arc materials in the south and the old detritus from the southwestern Yangtze Block) which is consistent with a back arc setting for the deposition of the sediments.Zircons from the upper part of the basement sequence (the Duyantang Formation and its equivalent) show euhedral and subangular morphology and display a unimodal age peak at ca.835 Ma.This sequence was possibly deposited in a convergent setting and the detritus were came from the locally distributed syn-collisional igneous rocks.The lower part of the cover sequence (the Xinzhai and Wuye formations and their equivalents) shows a distinct zircon age peak at 815-809 Ma and two subordinate peaks at 2485 Ma and 2018 Ma,suggesting that the basin had gradually transformed into a continental rift basin and received the detritus from the ca.815 Ma post-collisional magmatic rocks as well as from different Paleoproterozoic source rocks in the northern Yangtze Block.We propose a tectonic evolution model that envisages eruption of ca.840 Ma basalt in a back arc basin that existed during ca.870-835 Ma,an angular unconformity was formed during amalgamation of the Yangtze Block and the Cathaysia Block at ca.835-820 Ma and the rifting of the South China Continent was initiated at ca.800 Ma.Our study concludes that the South China Continent was formed on the periphery of the Rodinia supercontinent.Jiawei Zhang Taiping Ye Yaran Dai Jianshu Chen Hui Zhang Chuangu Dai Guohua Yuan Kaiyuan Jiang 2019Geoscience Frontiers2019,10,5:4
返回顶部 每页显示:
共8页 首页 上一页 第1页 下一页 末页 /8 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费