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141.
日本平面设计大师田中一光设计的戏剧海报作品中,能剧海报独树一帜。能剧海报多以日本传统的能面形象为基本元素,结合理性严谨的方格骨格,采用热情饱满的日本民族色彩,巧妙处理虚实关系,是民族与国际、传统与现代完美结合的典范。  相似文献   
142.
Objective: To investigate whether vascular endothelial growth factor (VEGF) gene plasmid carried by polytetrafluoroethylene (PTFE) vascular graft materials could transfect endothelial cells (ECs) and promote their growth. Methods: PTFE vascular graft materials carried with pCDI-hVEGF121, pCDI or pEGFP were incubated in Tris-buffer solution and the values of optical density of 260 nm at different time were plotted, then the DNA controlled release curve was made. ECs derived from human umbilical vein were seeded on the pCDI-hVEGF121/pCDI/pEGFP-PTFE materials or tissue culture plates, ECs numbers were counted and VEGF protein concentrations at different time were measured by enzyme-linked immunoadsorbent assay method. Green fluorescent protein (GFP) expression in ECs on pEGFP-PTFE materials was examined with fluorescence mi- croscopy. Results: The controlled release curve showed that the gene released from PTFE materials was rapid within 8 h, then slowed down and that the gene released continuously even after 72 h. At 24, 72 and 120 h, ECs number and proliferation rate of pCDI-hVEGFI21-PTFE materials were higher than those ofpCDI or pEGFP-PTFE materials (P〈0.05). VEGF protein concentration of pCDI-hVEGF121-PTFE materials was higher than that of pC DI or pEGFP-PTFE materials at 6, 24, 72 and 120 h (P〈0.01). GFP expression in ECs on the pEGFP-PTFE materials could be detected by fluorescence microscopy. Conclusion: PTFE graft can be used as a carrier of VEGF gene plasmid, VEGF gene carried by PTFE can transfect ECs and promote ECs growth.  相似文献   
143.
ABSTRACT

Subject ontology can help implement the structured organization of knowledge for online learners and thus plays an important role in the learning process. However, building ontologies by experts is time-consuming, and the adaptation of such ontologies to different contexts might be a problem. Crowdsourcing, which allows users to build and refine ontologies during their learning process, has exhibited potential for solving this problem. In this study, a crowdsourcing mode-based learning activity flow approach is proposed to guide the learning of online learners while promoting the generation and evolution of subject ontologies using the learners’ contributions to the learning content. This flow makes full use of the learners’ wisdom during the learning process to promote self-regulated learning as well as the generation and evolution of the ontology. Based on the proposed approach, a learning support system was developed and an experiment conducted involving a Chinese lesson on “The Liangzhou Poem”. In the experiment, student participants built 722 triples, of which 584 evolved as formal items in the subject ontology. Moreover, all learners were able to construct a well-organized knowledge graph. Students in both high- and low-scoring groups contributed valuably to the knowledge generation and evolution of the subject ontology. Furthermore, while the widths of the knowledge constructed by students in high- and low-scoring groups were similar, their depths were substantially different. During this process, the crowdsourcing-based activity flow system achieved satisfactory technique acceptance, which means that the proposed approach and system are useful for the effective generation of subject ontologies while helping learners acquire knowledge.  相似文献   
144.
通过观察不同剂量二甲基亚砜(dimethyl sulfoxide DMSO)作用下PC12细胞形态和生长状态的变化,确定PC12细胞对DMSO的耐受剂量.按照一定浓度梯度(V/V)将DMSO加入培养液干预后的24、48和72 h于倒置相差显微镜下观察AO/EB染色前后细胞的形态特征,同时用四甲基偶氮唑蓝(MTT)显色法检测细胞的生存率和计算半数抑制浓度(50%inhibiting concentration,IC50).结果表明:DMSO浓度为14 mL/L时,24 h内90%的PC12细胞生长正常,形态完整,活力与对照组比较无差别,浓度提高到20 mL/L时,24 h时细胞生存率可下降27%,随着作用时间延长,细胞生存率进一步降低;24、48和72 h对应的IC50值分别为31.4、23.9和19.2 mL/L.因此,对PC12细胞而言,24 h内的应用终浓度应低于14 mL/L,干预时间如需延长,DMSO的应用剂量应相应降低.  相似文献   
145.
ABSTRACT

This study operationalized Weick’s [(1988). Enacted sensemaking in crisis situations. Journal of Management Studies 25(4), 305–317 and (1993). The collapse of sensemaking in organizations: The Mann Gulch disaster. Administrative Science Quarterly, 38, 628–652] theory of enacted sensemaking to examine the communication processes associated with the Flint Water Crisis of 2014–2015. A content analysis of 389 emails and attachments from a total population of N?=?37,376 pages of publicly released e-mails and documents pertaining to Flint’s water issues, identified examples of failed sensemaking by government officials. These failures hastened and intensified a growing crisis of lead contamination and an outbreak of Legionnaires disease associated with Flint’s municipal water system. Analysis of email messages suggests that strong commitments by top leaders and limited capacity were important factors as were efforts to create and maintain consensus among officials. The Flint Water Crisis offers an important application of sensemaking theory and its utility for both organizational and risk communication scholars and for practical application. The authors emphasize the importance of questioning previous assumptions and commitments, insuring that communication practitioners are involved in decisions, and avoiding over reliance on image repair as a strategic response.  相似文献   
146.
数学期望是随机变量的重要的数字特征之一。本文通过民事纠纷、疾病普查和利润的例子探讨离散型随机变量的数学期望在法律、医学和经济等问题的应用。  相似文献   
147.
从神经生理谈老年性痴呆症的发病机制与疗法   总被引:2,自引:0,他引:2  
从神经生理的角度分析了老年痴呆症的发病机制,认为老年痴呆与胆碱能、单胺能、神经肽能等多种递质和调制物的功能障碍有着直接的联系,提出了根据病因采用中药、西药和康复3大类的治疗方法。  相似文献   
148.
采用半结构访谈的研究方法,对一位母亲患有精神疾病的子女进行访谈,深入了解了精神疾病患者子女的体验,并初步探讨了为患者子女营造良好生长环境的对策。  相似文献   
149.
对于莆仙戏演员而言各种嗓音病变直接影响歌唱者的舞台表现,严重者甚至会终止演员的职业生涯。本文通过对发声器官以及对导致嗓音疾病原因、症状进行的分析,有针对性地提出相关的音乐辅助疗法,以增强发声机能,从而达到莆仙戏演员的嗓音保健目的。  相似文献   
150.
进一步对ASP.NET 2.0中的GridView控件进行了深入分析与研究,探讨了GridView控件的更多高级应用。在扩展GridView控件的应用功能时主要采用.htc文件来进行代码封装。提出了对GridView控件的若干高级应用的思路,并给出了其实现方法。通过具体软件项目的应用与实践验证,取得了预期的效果。  相似文献   
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