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71.
本文对43例哮喘患者及20名正常人分别进行了血浆 TXB_26—keto PGF_(1a)放射免疫测定.其结果:哮喘患者发作期血浆 TXB_2明显高于缓解期,且哮喘者各期血浆 TXB_2均较正常人显著增高(P<0.05);病情越重,增高越明显;而6—keto PGF_(1a)各组间无显著差异(P>0.05)。结果表明血栓素 A_2可能在哮喘的发病机理中起着重要作用。  相似文献   
72.
本文讨论了概率模型方法的基本思想,并利用概率模型法证明了分析中著名的Cauchy-Schwarz不等式。  相似文献   
73.
从实例出发以景观化的思想对高校校园建设进行分析,提出重视校园户外空间建设和文化内涵。并就一些节点建设提出几点构思。  相似文献   
74.
为适应时代发展的要求 ,应把握“加强和改进高校学生教育管理工作”这一高校学生工作的主旋律 ,积极探讨新形势下搞好高校学生教育管理工作的对策  相似文献   
75.
多校区大学的产生,使得拥有多个校区的一所大学同时存在着具有不同特色的校区文化,因此,多校区大学都不同程度地存在着校园文化整合与重构的问题。在分析校园文化及其在多校区大学中的价值和多校区大学校园文化建设存在问题的基础上,提出整合和重构多校区大学校园文化的若干思路和对策。  相似文献   
76.
Objective: To determine the effective nucleotide sites of ribozymes against HCV, and obtain a highly effective, nontoxic and inexpensive antisense ribozyme specific for HCV. Methods: Two effective ribozymes, targeted to HCV 5’NC region and C region, were designed and synthesized. Eukaryotic expression vectors, pSV2-gpt. CD-SR (, containing either HCRZNC or HCRZC were constructued and transfected into MT-2 cells, which had been infected by HCV. Quantitative PCR and hydridization were used to determine the effect of inhibition of HCV by ribozymes. Results: HCRZNC and HCRZC suppressed the replication of HCV by 54.7% and 62.1%, respectively. Furthermore, when both ribozymes were cotransfected into cells, they suppressed replication by 78.8%. Conclusion: Two specific antisense ribozymes have strong inhibitory effects on the replication of HCV in cultured cells, and have better effect when used together.  相似文献   
77.
Mobile devices are increasingly powerful in multimedia transmitting and browsing. However, the small screen and different aspect ratios of mobile devices lower visual quality while watching images or videos. Video retargeting is aim at fitting an existing video into arbitrary size and aspect ratio. Previous content-aware retargeting methods are mostly high computational cost, which limits their applications on the portable devices with low computation ability. In this paper, a new crop-and-scale approach is presented to adapt video to better suit the target display. We automatically find the optimal parameters of cropping window using the dynamic programming method, and then scale it to fit the target display. The cropping window can smoothly shift during a shot to follow the movement of important objects. The retargeting results using our approach introduce no deformation and jitter effects over the whole video. Experimental results show the success of our approach on adapting a variety of source videos to small display sizes.  相似文献   
78.
澳大利亚职业教育迅速发展的原因探析   总被引:12,自引:1,他引:12  
20世纪70年代以来,澳大利亚职业教育迅速发展的主要原因是:重视职业教育,建立完整发达的职业教育体系,加大职业教育改革的力度,采取多种措施,加强政府统筹和宏观调控;确立能力本位的职业教育思想,引入竞争机制,建立市场化机制,采取形式多样的灵活的办学体制,不断增加职业教育投资,多渠道筹措职业教育经费,重视职业教育师资队伍建设。  相似文献   
79.
非物质文化遗产需要传承和弘扬,地方旅游业发展需要文化支撑,如何将二者融合发展,值得研究。本文收集、整理湖州非物质文化遗产资料,对其数量、类型、分布等进行分析,并实地调查了湖州旅游发展过程中对非物质文化遗产的利用现状,提出湖州乡村旅游应充分利用非物质文化遗产,可从打造舞台盛宴、创新导游解说、打造非遗属性旅游纪念品三个方面提升乡村旅游的文化内涵。这样,既可以更好地保护地方非物质文化遗产,又可以推动地方旅游文化事业,二者的结合是双赢之举。  相似文献   
80.
Objective: To construct a PC12 cell strain with neuronal differentiation, and observe the apoptosis and pro-liferation activity effects induced these cells by Amyloid beta-Protein (Aβ-43). Methods: 1) PC12 cells in logarithmicgrowth phase were subcultured for 24 h. After the culture fluid was changed, the cells were treated with Rat-β-NGF andcultured for 9 days. 2) Neuronal differentiation of PC12 cells in logarithmic growth phase were divided into four groups:control group (0), experimental group (1), experimental group (2) and experimental group (3). The concentrations of Aβ inthe four groups were 0 μmol/L, 1.25 μ mol/L, 2.5 μ mol/L and 5 μmol/L, respectively. The cells were harvested at 24, 48 and72 h later and stained with AnnexinV-FITC/PI after centrifugation and washing. Then flow cytometry was conducted toexamine the apoptosis percentage. 3) NGF-induced PC12 cells were selected and Aβ with different concentrations wasadded. The final concentrations of Aβ were 0 μmol/L, 1.25 μmol/L, 2.5 μmol/L and 5 μ mol/L, respectively. After the cellswere incubated in an atmosphere of 5% CO2 at 37 ℃ in an incubator for 72 h, the OD values were examined. Results: 1)Neuronal differentiated PC 12 cell lines were successfully established. 2) Flow cytometric examination indicated that Aβ(1.25, 2.5, and 5.0 μmol/L) could effectively induce apoptosis of neuronal-differented cells at the 24 h, 48 h and 72 h timepoints. 3) Aβ (0-5.00 μ mol/L) had no obvious effect on proliferation or restraining of the neuronal differentiation of thePC 12 cells after a 72 h interacting process. Conclusion: This investigation revealed successful neuronal differentiation of thePC12 cell strain. The induction of apoptosis of the neurocytes by various concentrations of Aβ was observed and the in-fluence of Aβ on induced proliferation of PC 12 cells by Rat-β-NGF was revealed. This study -05 provide basis for futureresearch on the molecular cure of AD and interdiction of AD evolution.  相似文献   
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