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51.
医学院校学生只有掌握英语写作知识和技能,才能以英语为工具进行有效的书面信息交流,从而促进医学文化的国际交流。此文探讨了提高医学院校英语写作教学质量的意义和策略,对促进医学院校大学英语教学改革有一定的指导意义。  相似文献   
52.
独立学院是处于探索、发展中的一种崭新的高校模式,受到社会大环境的种种因素的制约以及自身因素的影响,相关法规建设滞后。在其发展初期,不可避免还存在一些困难、问题以及矛盾。本文分析独立学院在发展中应该解决的几个普遍问题,并对其进一步发展提出了一些建议。  相似文献   
53.
崔金栋  郑鹊  孙硕 《情报科学》2017,35(12):22-27
【目的/意义】研究微博网络中话题式信息的传播模型及规律,对控制舆论和掌握微博信息传播规律具有重 要意义。【方法/过程】以微博信息传播中的SEIR模型为出发点,综合考虑微博网络中话题式信息的衍生特性,构建 改良式的微博话题式信息传播H-SEIR模型,并运用MATLAB进行模拟仿真,对微博中话题式信息传播影响因素 和对应的控制策略进行研究。【结果/结论】验证了所构建的改良微博话题式信息传播H-SEIR模型的可行性和有效 性,揭示了移动网络环境下话题式信息传播规律,为现实微博网络的监管控制策略的制定提供了理论依据。  相似文献   
54.
阙锐 《科技广场》2007,(6):51-53
曾有鱼米之乡之称的江西在近些年在全国的经济发展中处于倒数位置,几乎还是以第一产业为主的传统发展模式,没有发达的工业,但与此同时也给我们留下了良好的生态环境,为我省经济跨越式发展赶超发达地区留下自然基础。怎样利用良好的生态来发展我省经济成为首要的问题,因此,分析良好的生态环境对实施跨越式发展有着至关重要的作用,同时还需对江西实施跨越式发展优势进行一些探讨。  相似文献   
55.

Background

Tumor-derived exosomes were considered to be potential candidates for tumor vaccines because they are abundant in immune-regulating proteins, whereas tumor exosomal miRNAs may induce immune tolerance, thereby having an opposite immune function.

Objective

This study was designed to separate exosomal protein and depleted exosomal microRNAs (miRNAs), increasing the immune activity of exosomes for activating dendritic cell/cytokine-induced killer cells (DC/CIKs) against pancreatic cancer (PC).

Methods

PC-derived exosomes (PEs) were extracted from cultured PANC-1 cell supernatants and then ruptured; this was followed by ultrafiltered exosome lysates (UELs). DCs were stimulated with lipopolysaccharide (LPS), PE, and UEL, followed by co-culture with CIKs. The anti-tumor effects of DC/CIKs against PC were evaluated by proliferation and killing rates, tumor necrosis factor-α (TNF-α) and perforin secretion. Exosomal miRNAs were depleted after lysis and ultrafiltration, while 128 proteins were retained, including several immune-activating proteins.

Results

UEL-stimulated DC/CIKs showed a higher killing rate than LPS- and PE-stimulated DC/CIKs.

Conclusions

miRNA-depleted exosome proteins may be promising agonists for specifically activating DC/CIKs against PC.
  相似文献   
56.
The structural characteristics and optical and electrical properties of molecular-beam-epitaxy (MBE) grown ZnS0.8Se0.2 thin films on indium-tin-oxide(ITO) glas substrates were investigated in this work. TheX-ray diffraction (XRD) results indicated that high quality polycrystalline ZnS0.8Se0.2 thin film grown at the optimized temperature had a prefered orientation along the (111) planes. The transmission electron microscopy (TEM) cross-sectional micrograph of the sample showed a well defined columnar structure with lateral crystal dimension in the order of a few hundred angstroms. Ultraviolet (UV) photoresponsivity as high as 0.01 A/W had been demonstrated and for wavelengths longer than 450 nm, the response was down from the peak response by more than 3 orders of magnitude. The thin ZnS0.8Se0.2 photosensor layer, with a wide energy gap and anisotropic electrical property, makes a transmission UV liquid crystal light valve (LCLV) with high resolution feasible. Project supported by the National Natural Science Foundation of China (No. 59910161981) and RGC grant from the Hong Kong Government Grant (No. NSFC/HKUST 35), China  相似文献   
57.
INTRODUCTION Ensuring the integrity and safe operation of oil pipelines network is critical for ensuring the trans- portation of one of the most important forms of en- ergy. An inspection vehicle, called intelligent pig, which employs ultrasonic non-destructive testing technique is often used to inspect oil transmission pipelines (Okamoto et al., 1999; Reher et al., 2002). The ultrasonic detection principle involves the fun- damental concept that a propagating wave will be reflected and/o…  相似文献   
58.

Objective  

To evaluate the feasibility and superiority of a new coagulating and hemostatic method named “saline conducted electric coagulation (SCEC)”.  相似文献   
59.
Abstract

This study was designed to examine the perceptual and attentional processes associated with the effects of administering a cost-benefit precuing paradigm to intermediate and advance-level baseball batters. Psychophysiological and performance data obtained from 10 advanced and 10 intermediate-level players were compared. A total of 400 pitches (200 fastballs, 200 curveballs) was randomly presented via a large projection screen, and participants pressed one of two buttons to indicate the type of pitch thrown. Verbal precues were given for 300 of the pitches. Of those, 75% were valid, and 25% were invalid. Electroencephalographic data collected from the Pz location was used to assess the latency and amplitude of P300. Analysis of variance (Skill Level x Precue x Pitch) for P300 and reaction time (RT) indicated that intermediate batters produced shorter P300 latencies, larger P300 amplitudes, longer RTs, and less correct responses than the advanced batters; the effects were more pronounced for the curveballs. These results suggest that intermediate batters are less efficient in their perceptual decision-making processes due to greater limitations in attentional capacity when compared with advanced batters.  相似文献   
60.
Successfully recruiting students from underrepresented groups to pursue biomedical science research careers continues to be a challenge. Early exposure to scientific research is often cited as a powerful means to attract research scholars with the research mentor being critical in facilitating the development of an individual''s science identity and career; however, most mentors in the biological sciences have had little formal training in working with research mentees. To better understand mentors’ experiences working with undergraduates in the laboratory, we conducted semistructured interviews with 15 research mentors at a public university in the Midwest. The interviewed mentors were part of a program designed to increase the number of American Indians pursuing biomedical/biobehavioral research careers and represented a broad array of perspectives, including equal representation of male and female mentors, mentors from underrepresented groups, mentors at different levels of their careers, and mentors from undergraduate and professional school departments. The mentors identified benefits and challenges in being an effective mentor. We also explored what the term underrepresented means to the mentors and discovered that most of the mentors had an incomplete understanding about how differences in culture could contribute to underrepresented students’ experience in the laboratory. Our interviews identify issues relevant to designing programs and courses focused on undergraduate student research.  相似文献   
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