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141.
小河嘴水电站已运行四十多年,设备老化,故障多,自动化水平低,对该站进行增效扩容改造是必要的,而且也是可行的。  相似文献   
142.
袁盛华  高翔宇  马金福 《材料导报》2017,31(Z1):223-226
采用聚3,4-乙烯二氧噻吩(PEDOT)/FTO为对电极,研究了合成介质对循环伏安法电聚合制备的PEDOT/FTO对电极性能的影响。通过SEM、CV、EIS、Tafel曲线,并首次采用SECM方法对所制备的对电极的电催化性能进行了表征。结果表明:在LiClO4水溶液和1-丁基-3-甲基四氟硼酸盐离子液体(IL)中制备的光阴极具有良好的电催化性能。J-V测试曲线表明,在LiClO4水溶液和IL中制备的光阴极所组装的DSSC器件的光电转化效率分别达6.4%和6.6%,接近于同等条件下以Pt对电极构建的DSSC器件的光电转化效率。  相似文献   
143.
Pancreatic cancer is a dismal disease. The 5-year overall survival ranges from 1% to 5%. Surgery is the only curative treatment available for this cancer, but it is indicated only in selected patients with a less than 4 cm tumor. In these patients, survival rate is about 30%. We have considered several aspects: the very difficult early diagnosis, the correct diagnostic flow chart, actual surgical procedures and new trends in biologic and genetic research. It is likely that better results can be achieved by defining an "early pancreatic cancer" and establishing how to detect it. This could be the wrigth one way is to significantly improve the survival of these patients.  相似文献   
144.
Interference reflection microscopy (IRM) was used to evaluate the status of cell matrix adhesions in the MCF-7 human mammary carcinoma cell line. Focal contacts were concentrated at the periphery of individual cells or small cell clusters. Close contact was detected as a band at cell peripheries and as localized patches throughout the ventral face of cells. The MCF-7 cells also exhibited a distinctive reflection pattern of an intensity midway between that of either focal or close contact. This novel reflection pattern was located primarily at the periphery of cells and often obscured visualization of focal contacts in live cells. A similar distinctive pattern was absent from the normal tissue-derived MCF-10A mammary epithelial cell line. Immunofluorescence staining using an antiserum that cross-reacts with both alpha(v)beta3 and alpha(v)beta5 integrins revealed a distribution of the vitronectin receptor similar to that of the novel adhesion pattern as well as to that of focal contacts. In addition, IRM demonstrated the presence of "tracks" associated with cells, which were also stained with the vitronectin receptor antiserum. The tracks are apparently residual material left behind as a result of cell migration. When MCF-7 cells were cultured in the absence of estradiol, the tracks were greatly diminished when visualized with either IRM or staining for the vitronectin receptor. In contrast, the addition of 17-beta-estradiol to the medium resulted in an increased presence of the tracks as well as the development of extensive close contacts throughout the ventral surface of cells and cell clusters. Cells treated with the estrogen antagonist ICI 182,720 in the presence of estradiol had few associated tracks, indicating that the process leading to the formation of these structures is dependent on an estrogen receptor-activated pathway. However, the antagonist did not prevent the estradiol-induced formation of extensive close contacts. The extensive close contact as well as the increase in trailing material suggests that estradiol may promote breast tumor cell motility. However, this migratory activity may be mediated by both estrogen receptor-dependent and -independent pathways.  相似文献   
145.
The St. Francis Hospice Program is symbolic of more than 100 years of Franciscan dedication to the people of Hawaii. Since Mother Marianne's arrival in November of 1883, the Sisters of the Third Franciscan Order Syracuse, New York have responded to the calling; "the charity of Christ impels us." It is through this calling that care and comfort for the terminally ill is a part of the mission of St. Francis Healthcare System. The magnificent spirit through which Hospice services have been made possible, is a reflection of God's great generosity to us throughout the years.  相似文献   
146.
STUDY DESIGN: Cadaveric anatomic and in vivo survival animal studies were performed to develop a new arthrodesis technique for the lumbar spine. OBJECTIVES: To examine the feasibility, efficacy, and safety of a minimally invasive lumbar intertransverse process arthrodesis technique using an osteoinductive growth factor (rhBMP-2) delivered in a collagen sponge carrier. The technique was first developed using a rabbit model and modified for the nonhuman primate (rhesus monkey), a larger animal with the most similar bone biology to humans. SUMMARY OF BACKGROUND DATA: The morbidity of conventional posterolateral lumbar intertransverse process arthrodesis includes graft donor site morbidity; paraspinal muscle devascularization, denervation, and scarring and nonunion in up to 36% of patients. Minimally invasive anterior lumbar interbody arthrodesis techniques have been developed, but these often require a metal implant and carry risks to major vessels and development of retrograde ejaculation. A minimally invasive technique for posterolateral intertransverse process arthrodesis has not been described previously. METHODS: In Part 1, we examined seven New Zealand white rabbits and five rhesus monkeys at necropsy and during nonsurvival surgeries to determine the best access routes and to develop special instruments for video-assisted lateral intertransverse process arthrodesis. In Part 2, 38 New Zealand white rabbits underwent L4-L5 intertransverse process arthrodesis: the "OPEN" group (n = 16) underwent a standard open muscle-splitting approach using rhBMP-2 (bone morphogenetic protein) and collagen as a bone graft substitute; the "video-assisted control" group (n = 6) underwent video-assisted lateral intertransverse process arthrodesis with the collagen implant only (no growth factor); and the "video-assisted-BMP" group (n = 16) underwent video-assisted lateral intertransverse process arthrodesis with rhBMP-2 and collagen as the graft material. In Part 3, rhesus monkeys (n = 4) underwent video-assisted lateral intertransverse process arthrodesis using rhBMP-2 and collagen after laminectomy of L4-L5. RESULTS: In Part 1, we identified expedient, minimally invasive routes to the intertransverse process interval appropriate for each species: an intermuscular approach for the rabbit and a lateral, extramuscular approach for the rhesus monkey. In Part 2, all rabbits in the OPEN and video-assisted-BMP groups achieved solid intertransverse process lumbar fusions when assessed at 10 weeks. There were no neurologic impairments nor any difference between the two groups in the frequency of postoperative infection or other complications. None of the animals in the video-assisted control group showed evidence of fusion. In Part 3, exposure, decortication and grafting with rh-BMP-2 and collagen was accomplished successfully in all four monkeys through the video-assisted minimally invasive approach without complications. CONCLUSION: Video-assisted lateral intertransverse process arthrodesis is a feasible, effective, and safe method of lumbar spinal fusion in the rabbit and rhesus monkey. Use of this arthrodesis procedure will minimize the morbidity of paraspinal muscle denervation and devascularization seen with open intertransverse process fusion techniques, and the use of an osteoinductive growth factor will eliminate the problem of graft donor site morbidity and possibly increase the chances for successful fusion.  相似文献   
147.
软件项目进度控制方法研究   总被引:3,自引:0,他引:3  
为优化软件项目进度控制过程,使管理者能够对软件项目进度进行有效的跟踪和调整,研究并比较了主要的项目进度控制方法和技术,对甘特图、网络计划技术、关键链技术,对各技术的原理、适用范围、优缺点等进行了分析.为弥补上述技术的不足,引入工业项目进度控制方法--实际进度前锋线法,增强了对软件项目进度的信息统计和工期预测功能.通过对上述几种技术的改进和综合应用,提出了一个高效便捷的进度控制系统的设计方案.  相似文献   
148.
顶岗实习是高职院校重要的实践教学环节,要实现对顶岗实习的有效管理,需要借助网络技术搭建管理平台,实现对参与实习师生的管理与指导。该文在对顶岗实习流程及实习任务分析基础上,运用UML建模方法对系统进行分析建模与设计建模,并提出了系统框架与解决方案。  相似文献   
149.
This article proposes an asymmetric topology for transmit/receive (T/R) switches and more importantly presents a comparative study of both LC‐tuned and resistive body‐floating techniques for improving the power‐handling capability of the T/R switches in the same 0.18‐μm triple‐well CMOS. It is shown from simulations and measurements that the switches adopting either technique achieve comparable performances. For instance, the switch employing the LC‐tuned body‐floating technique exhibits insertion loss of 1.5 dB, isolation of 23.5 dB, and power‐handling capability of 22.5 dBm at 5.2 GHz, whereas the switch using the resistive body‐floating technique exhibits insertion loss of 1.3 dB, isolation of 24 dB, and power‐handling capability of 22.2 dBm, respectively. Therefore, one can conclude that the asymmetric topology with the resistive body‐floating technique is more suitable for designing T/R switches for wireless local area network applications as it consumes smaller silicon area. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010.  相似文献   
150.
媒体舆论引导仿真   总被引:1,自引:0,他引:1  
使用multi-Agent的建模思想,以现实为基础建立了一个舆论涌现的仿真模型.该模型主要由个体和媒体以及它们之间的规则组成.个体的属性包括了个体之间的信任度、个体观点的可信度和个体的从众性;媒体的属性包括媒体的影响范围和权威度.规则包括个体交互规则和个体与媒体的交互规则.通过仿真证明了模型是合理的,并且用该模型来仿真媒体对舆论演化的引导作用,从媒体的数量和报道频率2个方面研究媒体在舆论形成过程中的引导作用,结果发现积极媒体的数量越多对舆论的引导作用越强,媒体的报道频率增加会对舆论的形成产生积极效果,但是超过一定次数时对舆论的影响作用有限.最后通过对模拟结果的分析,提出了通过媒体来引导舆论的方式.  相似文献   
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