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201.
To evaluate the clinical outcome, effectiveness and safety of the surgical management of traumatic lumbar spondylolisthesis with transforaminal lumbar interbody fusion (TLIF) with short segmental instrumentation fixation. A retrospective review of a consecutive series of 24 patients with traumatic lumbar spondylolisthesis treated with TLIF procedure was carried out. Intraoperative spinal cord monitoring was used to confirm the peripheral neural function intact during the reduction of the spondylolisthesis. Preoperative clinical and radiographic evaluation of all cases were originally collected prospectively. Data regarding blood loss, operative time, duration of hospital stay, radiographic fusion, instrumentation failure and clinical result were collected and observed at regular follow-up periods. All patients were engaged in high-energy accidents in the lower back and 16 patients had concomitant injuries. The mean operative time was 124 min, mean blood loss was 350 mL, and mean hospital stay was 6.5 days. There were no complications such as incision infection, cerebrospinal fluide (CSF) leakage and nerve root injury and so on. All patients demonstrated a solid lumbar interbody fusion within 4 months, and no evidence of spondylolisthesis correction loss, instrumentation failure and loosing. They all were completely asymptomatic, with normal neurologic findings, and had resumed their previous level of physical activities on the final follow-up. Meticulous clinical examination and careful imaging assessment could assist an early diagonosis in cases of traumatic lumbar spondylolisthesis. Performing open reduction and the TLIF procedure as soon as possible could restore segmental stability and painless function. The TLIF procedure was a safe, effective technique to treat traumatic lumbar spondylolisthesis.  相似文献   
202.
Face recognition via adaptive image combination   总被引:1,自引:0,他引:1  
Dimension reduction and manifold learning are the two most popular feature extraction methods. The two methods focus on spatial locality as a guiding principle to find a low-dimensional basis for describing high-dimensional data, but no bases or features are more spatially localized than the original image pixels. So, adaptive image combination is presented to represent a class by a combined sample. The combined sample is a linear combination of original samples in the same class. Adaptive image combination (AIC) find the best combination coefficients by minimizing the intrapersonal distance and maximizing the interpersonal distance. Experimental results show that AIC is effective.  相似文献   
203.
染发剂毒性作用的研究进展   总被引:6,自引:0,他引:6  
着重叙述了近来染发剂毒性研究的进展,相关的流行病学调查,以及今后与染发剂有关的卫生工作中应当解决的问题。  相似文献   
204.
彭云  董猛  李相达 《水运工程》2019,(8):151-155
可再生能源具有环境友好、可循环利用等优点,综合利用可再生能源是绿色集装箱港口发展的必然趋势。应用系统仿真的方法量化港口装卸生产能源消耗量,结合环境经济效益计算方法定量分析可再生能源替代传统能源的环境经济效益。以某港区采用风力发电为例,对比分析集卡、岸桥和场桥能源替代后的环境效益与经济效益。  相似文献   
205.
介绍了曲塔混合梁斜拉桥的结构形式和稳定性分析方法。根据曲塔混合梁斜拉桥的受力特点,建立斜拉桥施工阶段几何非线性分析的有限元模型,完成了斜拉桥施工过程的仿真分析。在考虑了几何非线性和材料非线性效应的基础上,进行斜拉桥施工阶段和成桥状态的稳定性分析。结果表明,几何非线性对结构整体稳定性影响显著,在考虑几何非线性效应的基础上,材料非线性对稳定性的影响可忽略不计。  相似文献   
206.
采用王水湿式消化处理样品,建立了ICP-AES法同时测定霍加拉特剂中Mn、Cu、Na、Al、Ca、Mg和Fe等7种金属元素的方法。通过谱线选择、条件优化和基体匹配等方法消除元素间干扰和基体效应,探讨了酸类型及酸度值对谱线强度的影响,研究了溶液浓度对精密度及线性相关系数的影响。方法的线性相关系数均大于0.999,Mn、Cu、Na、Al、Ca、Mg和Fe的最佳谱线分别为Mn257.610nm、Cu327.393nm、Na589.592nm、Al396.153nm、Ca317.933nm、Mg285.213nm、Fe238.204nm,相应的检出限分别为0.0008、0.0009、0.012、0.028、0.010、0.001、0.004μg/mL,对应测定值的相对标准偏差分别为0.34%、0.87%、0.87%、0.54%、0.48%、0.84%、0.55%,加标回收率为94.2%~104.4%。该方法简便、快捷、准确,可在测定其他催化剂中金属含量时推广应用。  相似文献   
207.
In an attempt to reduce CO2 emissions from motorized transport, the Taiwanese government introduced an idling stop policy for vehicles in early 2007. This paper seeks to quantify the environmental benefits of the policy based on a stated preference analysis. Motorcyclists were surveyed at urban intersections in Taiwan, to identify the amount of time they would be willing to turn off their engines while waiting at traffic lights (the WTO). A contingent valuation framework based on stated preference questions was designed to determine the WTO. Results obtained from the Spike model showed that the average motorcyclist’s WTO is 82 s. In another analysis, in which other variables were taken into consideration, such as the possibility that the policy will be enacted as legislation, the expected WTO increased to 101 s. In both cases, an idling stop policy would have positive environmental effects, reducing gasoline usage by 1021 L per hour and reducing CO2 emissions by 0.56 metric tons per hour at the intersection studied during peak periods.  相似文献   
208.
“低碳经济”背景下公路隧道照明节能策略   总被引:6,自引:0,他引:6  
目前我国公路隧道运营照明存在的突出问题主要表现在:照明设计参数有待完善、照明控制方式较为落后、照明节能理念存在误区、照明设施养护未得重视。文章基于建设"环境友好型"公路隧道理念,从系统工程角度提出公路隧道照明节能的15项重要措施,包括准确测试洞外亮度、优化照明设计参数、选择使用节能光源等,基本涵盖公路隧道照明技术性节能、结构性节能、管理性节能的各个方面。工程实践表明,这些技术和措施可实现公路隧道照明综合节能20%以上的总体目标,具有较好的生态效益、经济效益和社会效益。  相似文献   
209.
This paper seeks to improve our understanding of passengers’ behavioral intention by proposing an integrated framework from the attitudinal perspective. According to the literature in marketing research, we establish a causal relationship model that considers “service quality-satisfaction-behavioral intentions” paradigm, perceived value theory, and switching barrier theory. Exploring passengers’ behavioral intention from satisfaction and perceived value help to understand how passengers are attracted by the company, while switching barriers assist in realizing how passengers are “locked” into a relationship with the current company. Furthermore, in order to capture the nature of service quality, we adopt a hierarchical factor structure which serves service quality as the higher-order factor. In this study, coach industry is selected as our research subject. The empirical results, as hypothesized, show that all causal relationships are statistically significant, and perceived value us the most important predictor of satisfaction and passengers’ behavioral intention. In conclusion, the managerial implications and suggestions for future research are discussed.  相似文献   
210.
引入移动汇聚节点解决无线传感器网络高效数据收集问题.网络中固定汇聚节点与移动汇聚节点共存,全部传感器节点都拥有维护到固定汇聚节点的路由,移动汇聚节点进入网络后定期向其附近小范围内的传感器节点扩散自己的声明信息,传感器节点向距自己跳数最小的汇聚节点发送或转发数据包.移动汇聚节点和距离其一跳的传感器节点之间通过有效的应答机制来保证数据的可靠传输.通过仿真结果显示引入移动汇聚节点的数据收集在节省能耗方面明显优于传统网络.在延长网络生存时间的同时,可以获得较高的数据传输成功率和较短的数据传输延迟.  相似文献   
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