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221.
一、对国内外教育研究生培养的探讨(一)概况通过比较分析,我国应着重研究下述课题:1.研究和协调教育研究生的学科专业布局结构、学科课程发展和软硬件资源分布合理性的问题。2.研究教育专业主动适应新形势的需求,着重培养教育研究生主动探讨教育改革动向的能力、定向教育教学科  相似文献   
222.
本文根据自治区对全疆中小学教师进行专业基础知识水平的测试的要求,给出了用visual foxpro 6.0数据库管理系统编制的实现考生准考证号的编排的程序段。  相似文献   
223.
Objective: McKeown esophagectomy followed by cervical and abdominal procedures has been commonly used for invasive esophageal carcinoma. This minimally-invasive operative procedure in the lateral prone position has been considered to be the most appropriate method. We describe our experiences in minimally invasive McKeown esophagectomy (MIME) for esophageal cancer. Methods: Between March 2016 and February 2018, a total of 82 patients underwent MIME by a single group in our department (a single center). All procedure, operation, oncology, and complication data were reviewed. Results: All MIME procedures were completed successfully, with no conversions to open surgery. The median operative time was 260 min, and median blood loss was 100 ml. The average number of total harvested lymph nodes was 20.1 in the chest and 13.5 in the abdomen. There were no deaths within 30 postoperative days. Twenty cases (24.4%) developed postoperative complications, including anastomotic leak in 4 (4.9%), single lateral recurrent nerve palsy in 4 (4.9%), bilateral recurrent nerve palsy in 1 (1.2%), pulmonary problems in 3 (3.7%), chyle leak in 1 (1.2%), and other complications in 7 (including pleural effusions in 4, incomplete ileus in 2, and neck incision infection in 1; 8.54%). Average postoperative hospitalization time was 12 d. Blood loss, operation time, morbidity rate, and the number of harvested lymph nodes were analyzed by evaluating learning curves in different periods. Significant differences were found in operative time (P=0.006), postoperative hospitalization days (P=0.015), total harvested lymph nodes (P=0.003), harvested thoracic lymph nodes (P=0.006), and harvested abdominal lymph nodes (P=0.022) among different periods. Conclusions: Surgical outcomes following MIME for esophageal cancer are safe and acceptable. The MIME procedure for stages I and II could be performed proficiently and reached an experience plateau after approximately 25 cases.  相似文献   
224.
在属性权重完全未知时,介绍了一种决策矩阵排序的最优化方法。首先,建立了最优化模型,其次,给出了该模型的算法,最后,举例说明该方法的有效性和可行性。  相似文献   
225.
Xu  Lei  Li  Yonghong  Zhu  Jiang  Liu  Zhiyuan 《天津大学学报(英文版)》2019,25(4):312-321
The adsorption performance of toluene on ultra-stable Y zeolite(USY) was studied via dynamic adsorption. The effects of bed temperature, initial concentration, and feed flow rate on adsorption were investigated. The Yoon–Nelson model was used to fit the toluene breakthrough curves. The length of mass transfer zone was calculated based on breakthrough curves. The Langmuir–Freundlich model fit the adsorption isotherms of toluene on USY, which indicated that the surface of USY was heterogeneous. The adsorption isosteric heat calculated from adsorption isotherms ranged from 54.3 to 69.8 kJ/mol, indicating physical adsorption. The combined technique of temperature swing adsorption with vacuum swing adsorption(TVSA) exhibited excellent desorption performance, which was attributed to the low desorption activation energy. Under optimized TVSA conditions, the desorption rate of toluene reached 90.6% within 10 min. The long-term cyclic utilization results indicated that the adsorption capacity of USY was stable.  相似文献   
226.
INTRODUCTION tic in-betweening techniques have been proposed during the past 30 years (for a comprehensive review of automatic in-betweening methods, please refer to (Yu and Patterson, 1997; Gotsman and Surazhsky, 2001)), their use in computer aided systems is some- how limited to dealing with local movements only (Yu and Patterson, 1997), because exaggerated drawings used in cartoon animations follow animation princi- ples and do not respect the geometry (Patterson and Willis, 1994) tha…  相似文献   
227.
实现比资本主义国家更高的社会公平,是构建社会主义和谐社会的目标和条件。胡锦涛同志在省部级主要领导干部提高构建社会主义和谐社会能力专题研讨班上的讲话和党的十六届六中全会通过的《中共中央关于构建社会主义和谐社会若干重大问题的决定》,坚持马克思主义公平观的基本原理,并结合我国社会主义初级阶段的具体实际,深刻揭示了当今中国实现社会公平的根本目的和现实途径,丰富和发展了马克思主义的公平观。在我国实现社会公平必须坚持以公有制和按劳分配为主体的基本经济制度,必须坚持人民当家作主的基本政治制度,必须建立一套与我国社会主义初级阶段的实际国情相适应的具体制度和体制。  相似文献   
228.
Objective: To investigate the effect of interleukin-18 (IL-18) on immune response induced by plasmid encoding hepatitis B virus middle protein antigen and to explore new strategies for prophylactic and therapeutic HBV DNA vaccines. Methods: BALB/c mice were immunized with pCMV-M alone or co-immunized with pcDNA3-18 and pCMV-M and then their sera were collected for analysing anti-HBsAg antibody by ELISA; splenocytes were isolated for detecting specific CTL response and cytokine assay in vitro. Results: The anti-HBs antibody level of mice co-immunized with pcDNA3-18 and pCMV-M was slightly higher than that of mice immunized with pCMV-M alone, but there was not significantly different (P>0.05). Compared with mice injected with pCMV-M, the specific CTL cytotoxity activity of mice immunized with pcDNA3-18 and pCMV-M was significantly enhanced (P<0.05) and the level of IFN-γ in supernatant of splenocytes cultured with HBsAg in vitro was significantly elevated (P<0.05) while the level of IL-4 had no significant difference (P>0.05). Conclusion: The plasmid encoding IL-18 together with HBV M gene DNA vaccines may enhance specific TH1 cells and CTL cellular immune response induced in mice, so that IL-18 is a promising immune adjuvant.  相似文献   
229.
lintroductionCompressionofdigitalimagesandvideosignalstoreducetheirstorageandtransmissionbandwidthrequirementsisofgreatinterestintheimplementationofcolnnlunicationsystems.Moreandmorecompressioncodingmethod$fordigitalimagesandvideosignalshavebeenproposedto…  相似文献   
230.
本文在内参量热力学的理论框架内详细讨论了线弹性裂纹体的裂纹扩展问题。对线弹性断裂力学中所涉及到的各种能量关系作了统一的整理,其中包括Irwin的弹性能释放率——裂纹扩展力,Griffith的脆性断裂准则,以及Irwin-Kies的柔度公式和Paris的位移公式。本文以中心裂纹体为例,详细计算了裂纹扩展的稳定性,并区分恒载荷和恒位移两种情况,对材料断裂韧性测试中所遇到的失稳扩展,稳定扩展以及进发现象提供了理论说明。  相似文献   
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