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    题名 作者 年代 出处 被引量
1试论“超市+农产品加工企业+农户”新模式显示文摘目前,中国面临着不断增长的对安全、优质农产品的市场和出口需求同大量分散的、无组织的小规模家庭生产的矛盾。本文提倡采用“超市+农产品加工企业(农民合作组织)+农户”的新型农业产业化模式,通过整个农产品供应链管理来确保农产品的安全。胡定寰 Fred Gale Thomas Reardon 2006农业经济问题2006,27,1:100
2变革型领导对员工绩效和满意度的影响:心理资本的中介作用及程序公平的调节作用显示文摘通过对国内一家企业共785位员工及其直接主管的问卷调查,考察了下属心理资本在变革型领导与下属工作绩效及满意度之间关系的中介作用以及程序公平对该关系的调节作用。研究结果显示:1)下属的心理资本与其工作绩效和满意度正向相关;2)下属的心理资本部分中介了变革型领导对下属工作绩效及满意度的正向关系;3)下属的程序公平调节了变革型领导对下属心理资本的影响。具体而言,下属的程序公平感越高,变革型领导与下属心理资本的正向关系越强,反之越弱;4)进一步地,程序公平调节了下属心理资本对变革型领导-工作绩效和满意度的中介作用,即:程序公平感越高,变革型领导通过心理资本对下属的工作绩效和满意度所产生的作用就越强,反之越弱。最后讨论了该研究的理论意义和应用价值。隋杨 王辉 岳旖旎 Fred Luthans 2012心理学报2012,44,9:122
3Detection of tumor stem cell markers in pancreatic carcinoma cell lines显示文摘BACKGROUND: Cancer of the pancreas is the fourth leading cause of cancer death in industrialized countries. In malignancy, actively proliferating cells may be effectively targeted and killed by anti-cancer therapies, but stem cells may survive and support re-growth of the tumor. Thus, new strategies for the treatment of cancer clearly will also have to target cancer stem cells. The goal of the present study was to determine whether pancreatic carcinoma cell growth may be driven by a subpopulation of cancer stem cells. Because previous data implicated ABCG2 and CD133 as stem cell markers in hematopoietic and neural stem/progenitor cells, we analyzed the expression of these two proteins in pancreatic carcinoma cell lines. METHODS: Five established pancreatic adenocarcinoma cell lines were analyzed. Total RNA was isolated and real- time RT-PCR was performed to determine the expression of ABCG2 and CD133. Surface expression of ABCG2 and CD133 was analyzed by flow cytometric analysis. RESULTS: All pancreatic carcinoma cell lines tested expressed significantly higher levels of ABCG2 than non-malignant fibroblasts or two other malignant non- pancreatic cell lines, i.e., SaOS2 osteosarcoma and SKOV3 ovarian cancer. Elevated CD133 expression was found in two out of five pancreatic carcinoma cell lines tested. Using flow cytometric analysis we confirmed surface expression of ABCG2 in all five lines. Yet, CD133 surface expression was detectable in the two cell lines, A818-6 and PancTu1, which exhibited higher mRNA levels.CONCLUSIONS: Two stem cell markers, ABCG2 and CD133 are expressed in pancreatic carcinoma cell lines. ABCG2 and/or CD133 positive cells may represent subpopulation of putative cancer stem cells also in this malignancy. Because cancer stem cells are thought to be responsible for tumor initiation and its recurrence after an initial response to chemotherapy, they may be a very promising target for new drug developments.Monika Olempska Patricia Alice Eisenach Ole Ammerpohl Hendrik Ungefroren Fred Fandrich Holger Kalthoff 2007Hepatobiliary & Pancreatic Diseases International2007,6,1:69
4工程因素对页岩气产量的影响——以北美Haynesville页岩气藏为例显示文摘我国页岩气开发尚处于前期探索阶段,分析国外成功的开发案例具有重要的借鉴作用和参考价值。在对北美Haynesville页岩气藏生产数据进行统计和分析的基础上,总结了工程因素对该页岩气藏开发的影响规律。结论认为:页岩气井水平段长度、压裂级数、加砂量、油嘴尺寸、井底压力和是否采取重复压裂施工对累积产量有显著影响;水平段长度在1 500~1 650m之间、压裂级数12~17级、加砂量1 500~3 000t、油嘴尺寸8~9mm为该地区常用且效果较好的设计方案;井底压力高的区域页岩气产量相应较高,这与井底超压改善页岩脆性、优化压裂效果有关;重复压裂能够显著提高页岩气总产量,作业时机的选择与增产效果关系密切。李庆辉 陈勉 Fred P.Wang 金衍 李志猛 2012天然气工业2012,32,4:77
5品味:主动用心地感受积极体验显示文摘品味(savoring)是积极心理学中的一个重要概念,它主要指个体延长和增强积极体验的过程。本文在介绍Bryant和Veroff的品味理论基础上,结合最新研究进一步对品味的概念、结构、机制、测量进行系统论述,并探讨了品味和幸福感的关系以及提高品味能力的方法。除了需要在品味的神经生理机制、品味的毕生发展研究、品位的文化差异等一些研究领域继续努力外,品味的测量以及应用等问题也都值得未来研究注意。郭丁荣 任俊 张振新 Fred B. Bryant 2013心理科学进展2013,21,7:35
6实况海温强迫的CCM3模式对中国区域气候的模拟能力显示文摘使用NCAR/CCM3全球环流模式进行了 5个集合 1 9年 ( 1 979~ 1 997)时间长度的观测海温强迫的AMIP2试验 ,对结果的中国区域部分进行了重点分析。首先给出了模式对中国地区基本气候态的模拟 ,表明模式对这些区域的气温有较好的模拟效果 ,对降水的模拟效果则比较差。随后 ,考察了模式对历年中国汛期降水和气温的模拟预测 ,结果表明 ,模式对中国整体降水的模拟预测能力较差 ,但分地区看 ,则在长江流域地区的效果较好 ;模式对中国汛期气温有较好的模拟能力 。高学杰 林万涛 Fred Kucharsky 赵宗慈 2004大气科学2004,28,1:30
7谷胱甘肽转硫酶M1和T1基因型与食管癌危险性:病例-对照研究显示文摘为探讨参与致癌物代谢的谷胱甘肽转硫酶(GST)MI和T1基因多型性与食管癌危险性的关系,以病例-对照分子流行病学方法,分析食管癌高发区河南林县的食管癌、食管上皮重度增生病例和性别、年龄配对的正常对照者(各45例)的GSTM1和GSTT1基因型分布的差异。基因组DNA来自研究对象的食管外科手术标本或细胞学检查获得的食管上皮细胞,以多重聚合酶链反应方法进行基因分型。结果:食管癌、食管上皮重度增生病例和正常对照组GSTM1基因缺失率分别为44.4%、44.4%和46.7%;GSTT1基因缺失率分别为40.0%、37.8%和51.1%,差别均无显著性。然而,正常对照者中既是GSTMl阳性又是GSTT1阳性的基因型比例(22.2%)显著低于食管癌病例(40.0%)和食管上皮重度增生病例(37.8%),比值比(95%可信限)分别为4.20(1.23~14.36)和2.64(0.84~8.30)。结果提示,GSTM1或GSTT1基因多型性单独似乎与食管癌危险性无关,但两者的阳性基因型联合可能是食管癌的危险性因素。林东昕 唐永明 陆士新 Fred F.Kadlubar 1998中华流行病学杂志1998,19,4:27
8基于分布式最大功率跟踪的光伏系统输出特性分析显示文摘分布式最大功率跟踪(DMPPT)光伏系统可以有效地抑制实际环境中因为光照不均影响所造成的产电率下降的问题。以DMPPT的光伏系统为研究对象,针对多个分布式最大功率跟踪模块组网的优化问题,基于系统静态输出特性对多个光伏优化模块级联的结构进行了分析,提出了一种新型的DMPPT光伏系统结构。通过分析和研究,阐明了光照条件、系统结构及单个光伏优化模块本身限压值、限流值等参数与光伏阵列最大输出功率之间的关系。所提出的新型DMPPT光伏系统结构可以保证在不同的光照条件下每块光伏板都可以工作在各自的最大功率点,该结构有效地提高了光伏阵列在失配问题下产电率,并且适用于高电压母线系统。最后搭建了实验平台,通过硬件实验平台验证了所提出的新型DMPPT光伏系统结构对光伏系统产电率的优化效果。王丰 孔鹏举 Fred C.Lee 卓放 2015电工技术学报2015,30,24:27
9A multi-metric approach for research evaluation显示文摘Background information is provided about the Web 2.0 related term altmetrics. This term is placed in the context of the broader field of informetrics. The term influmetrics is proposed as a better term for altmetrics. The importance of considering research products and not just scientific publications is highlighted. Issues related to peer review and making funding decisions within a multi-metric approach are discussed and brought in relation with the new metrics field.RONALD Rousseau FRED Y Ye 2013Chinese Science Bulletin2013,58,26:25
10嵌入式智能光伏模块的最大功率输出统一控制显示文摘传统的太阳能系统经常会因为实际应用环境中的不匹配问题和光照不均现象而影响效率。分布式最大功率跟踪(distributed max power point tracking,DMPPT)概念的提出有效地抑制了这种影响。在分布式最大功率跟踪的基础上,该文提出一种嵌入式智能光伏模块(sub-panel MPPT converter,SPMC),利用非隔离的DC-DC变换器替代传统太阳能板接线盒中的旁路二极管,通过输出侧统一的最大功率计算单元对输入侧进行的指令信号控制,可以有效地消除太阳能板因为不匹配问题所带来的能量损失。文中首先对所提出智能光伏模块的拓扑结构进行分析、比较。然后以BUCK型的嵌入式智能光伏模块提出统一输出最大功率跟踪控制策略,这种控制策略在保证输出功率最大化的前提下,优化了系统模块,有效降低了系统控制复杂度和装置成本。最后,文章通过实验验证了所提出的概念和控制方法。王丰 吴新科 Fred C.Lee 卓放 2013中国电机工程学报2013,33,21:22
11运动损伤的心理学显示文摘Daniel Gould Linda M.Petlichkoff Bill Prentice Fred Tedeschi 艾华 2000体育科学2000,20,6:21
12氮化镓功率晶体管三电平驱动技术显示文摘作为第三代半导体材料的典型代表,宽禁带半导体氮化镓(GaN)材料具有许多硅材料所不具备的优异性能,是高频、高压、高温和大功率应用的优良半导体材料,无论在民用或是军事领域都具有广阔的应用前景。随着GaN技术的进步,大直径硅(Si)基GaN外延技术逐步成熟并向商用化方向发展。2010年以来,多家国际著名半导体厂商相继推出GaN功率晶体管器件。与硅半导体功率器件一样,合理的驱动方式也是GaN功率晶体管优越性能得以体现的重要保障。本文将以GaN功率器件在同步整流Buck变换器中的应用为例,提出一种三电平的驱动方式,以充分发挥GaN功率晶体管器件的优越性。实验结果表明,本文提出的三电平驱动方式可以有效提高变换器的效率。任小永 David Reusch 季澍 穆明凯 Fred C Lee 2013电工技术学报2013,28,5:19
13纺织品液态水分管理性能的测试方法显示文摘介绍了利用液态水分管理测试仪测试纺织品液态水分管理性能的方法,该仪器可测试织物的面层和里层的浸湿时间、面层和里层的吸水速度、面层和里层的最大浸湿半径、面层和里层的液态水分扩散速度、累积单向传递能力以及整体液态水分管理能力等10个指数,并将指数进行分级。该仪器可全面、客观地评估织物的三维湿度扩散及转移特性。Fred Cheng John Crocker 2008针织工业2008,,7:15
14济南岩溶泉域地下水流模拟显示文摘为深入研究济南岩溶泉域地下水资源变化的现状及未来发展趋势,探索地下水资源可持续管理途径,文章建立了济南泉域地下水稳定流和非稳定流模拟模型,分析了地下水流场及泉水流量变化趋势,并圈划了泉群地下水汇流带。在泉群汇流带内开采地下水直接影响泉流量,而水源地开采通过影响泉群汇流带间接影响泉流量。泉流量呈明显的季节性变化,且与降水量紧密相关:丰水期水位升高,泉流量增加;枯水期水位降低,泉流量减少。保护天然补给量与增加人工补给量是保证泉水长流的重要措施。王庆兵 段秀铭 高赞东 Fred Kloosterman 周仰效 李文鹏 2009水文地质工程地质2009,36,5:14
15Neural stem cells:mechanisms and modeling显示文摘In the adult brain,neural stem cells have been found in two major niches:the hippocampus and the olfactory bulb.Neurons derived from these stem cells contribute to learning,memory,and the autonomous repair of the brain under pathological conditions.Hence,the physi-ology of adult neural stem cells has become a signifi-cant component of research on synaptic plasticity and neuronal disorders.In addition,the recently developed induced pluripotent stem cell technique provides a powerful tool for researchers engaged in the patho-logical and pharmacological study of neuronal disor-ders.In this review,we briefly summarize the research progress in neural stem cells in the adult brain and in the neuropathological application of the induced pluripotent stem cell technique.Jun Yao Yangling Mu Fred H.Gage 2012Protein & Cell2012,3,4:12
16Inflammatory bowel disease and thromboembolism显示文摘Patients with inflammatory bowel disease(IBD) have an increased risk of vascular complications. Thromboembolic complications,both venous and arterial,are serious extraintestinal manifestations complicating the course of IBD and can lead to significant morbidity and mortality. Patients with IBD are more prone to Thromboembolic complications and IBD per se is a risk factor for thromboembolic disease. Data suggest that thrombosis is a specific feature of IBD that can be involved in both the occurrence of thromboembolic events and the pathogenesis of the disease. The exact etiology for this special association between IBD and thromboembolism is as yet unknown,but it is thought that multiple acquired and inherited factors are interacting and producing the increased tendency for thrombosis in the local intestinal microvasculature,as well as in the systemic circulation. Clinicians' awareness of the risks,and their ability to promptly diagnose and manage TEs are of vital importance. In this review we discuss how thromboembolic disease is related to IBD,specifically focusing on:(1) the epidemiology and clinical features of thromboembolic complications in IBD;(2) the pathophysiology of thrombosis in IBD;and(3) strategies for the prevention and management of thromboembolic complications in IBD patients.Petros Zezos Georgios Kouklakis Fred Saibil 2014World Journal of Gastroenterology2014,20,38:12
17降低固井水泥浆密度的新技术显示文摘针对现有低密度固井水泥浆存在的一些问题,介绍了一种有效降低水泥浆密度的新技术,即使用新型密度减轻材料———美国3M公司生产的中空玻璃微球(HGS)作为密度减轻剂。介绍了中空玻璃微球HGS的基本特点,对HGS低密度水泥浆进行了杨氏模量和抗张强度实验、压力和温度循环下的胶结强度实验、钻穿测试实验及现场测试,并与泡沫水泥浆和硅酸钠水泥浆进行了对比。实验及测试结果表明,添加了中空玻璃微球HGS的水泥浆有效地降低了密度,并且其混合、泵送及抗压强度、胶结质量等完全可以满足井下作业的要求。Fred Sabins 2006钻井液与完井液2006,23,4:11
18Intelligent Wireless Communications Enabled by Cognitive Radio and Machine Learning显示文摘The ability to intelligently utilize resources to meet the need of growing diversity in services and user behavior marks the future of wireless communication systems. Intelligent wireless communications aims at enabling the system to perceive and assess the available resources, to autonomously learn to adapt to the perceived wireless environment, and to reconfigure its operating mode to maximize the utility of the available resources. The perception capability and reconfigurability are the essential features of cognitive radio while modern machine learning techniques project great potential in system adaptation. In this paper, we discuss the development of the cognitive radio technology and machine learning techniques and emphasize their roles in improving spectrum and energy utility of wireless communication systems. We describe the state-of-the-art of relevant techniques, covering spectrum sensing and access approaches and powerful machine learning algorithms that enable spectrum and energy-efficient communications in dynamic wireless environments. We also present practical applications of these techniques and identify further research challenges in cognitive radio and machine learning as applied to the existing and future wireless communication systems.Xiangwei Zhou Mingxuan Sun Geoffrey Ye Li Biing-Hwang (Fred) Juang 2018China Communications2018,15,12:10
19^(40)Ar/^(39)Ar ages of seamount trachytes from the South China Sea and implications for the evolution of the northwestern sub-basin显示文摘A chronological study of seamount rocks in the South China Sea basin provides a great opportunity to understand the expansion and evolution history of the sea basin.In this paper,we analyzed the40Ar/39Ar age of trachytic samples collected from the Shuangfeng seamounts in the northwestern sub-basin of the South China Sea.The two samples yielded plateau ages of 23.80 0.18 and 23.29 0.22 Ma,respectively,which indicate magmatic activity in late Oligocene which helpful constraints the expansion time of the northwest sub-basin.Previous studies suggested that the northwestern sub-basin and southwestern sub-basin have experienced a relatively consistent expansion in the NWeSE direction followed by a late expansion of the eastern sub-basin.We concluded that the expansion of the northwestern sub-basin began prior to ca.24 Ma,which also implicated magmatic events of a late or stop expansion of the northwestern sub-basin combined with our results of40Ar/39Ar age data and previous geophysical data.Xiaohu Li Jiabiao Li Xing Yu Chunsheng Wang Fred Jourdan 2015Geoscience Frontiers2015,6,4:9
20Reliability in endoscopic diagnosis of portal hypertensive gastropathy显示文摘AIM: To analyze reliability among endoscopists in diagnosing portal hypertensive gastropathy (PHG) and to determine which criteria from the most utilized classifications are the most suitable. METHODS: From January to July 2009, in an academic quaternary referral center at Santa Casa of S o Paulo Endoscopy Service, Brazil, we performed this singlecenter prospective study. In this period, we included 100 patients, including 50 sequential patients who had portal hypertension of various etiologies; who were previously diagnosed based on clinical, laboratory and imaging exams; and who presented with esophageal varices. In addition, our study included 50 sequentialpatients who had dyspeptic symptoms and were referred for upper digestive endoscopy without portal hypertension. All subjects underwent upper digestive endoscopy, and the images of the exam were digitally recorded. Five endoscopists with more than 15 years of experience answered an electronic questionnaire, which included endoscopic criteria from the 3 most commonly used Portal Hypertensive Gastropathy classifications (McCormack, NIEC and Baveno) and the presence of elevated or flat antral erosive gastritis. All five endosco- pists were blinded to the patients' clinical information, and all images of varices were deliberately excluded for the analysis. RESULTS: The three most common etiologies of portal hypertension were schistosomiasis (36%), alcoholic cirrhosis (20%) and viral cirrhosis (14%). Of the 50 patients with portal hypertension, 84% were Child A, 12% were Child B, 4% were Child C, 64% exhibited previous variceal bleeding and 66% were previously endoscopic treated. The endoscopic parameters, presence or absence of mosaic-like pattern, red point lesions and cherry-red spots were associated with high inter-observer reliability and high specificity for diagnosing Portal Hypertensive Gastropathy. Sensitivity, specificity and reliability for the diagnosis of PHG (%) were as follows: mosaic-like pattern (100; 92.21; High); fine pink speckling (56; 76.62; Unsatisfactory); superficial reddening (69.57; 66.23; Unsatisfactory); red-point lesions (47.83; 90.91; High); cherry-red spots (39.13; 96.10; High); isolated red marks (43.48; 88.31; High); and confluent red marks (21.74; 100; Unsatisfactory). Antral elevated erosive gastritis exhibited high reliability and high specificity with respect to the presence of portal hypertension (92%) and the diagnosis of portal hypertensive gastropathy (88.31%). CONCLUSION: The most suitable endoscopic criteria for the diagnosis of PHG were mosaic-like pattern, redpoint lesions and cherry-red spots with no subdivisions,which were associated with a high rate of inter-observer reliability.George Fred Soares de Macedo Fabio Gon alves Ferreira Maurício Alves Ribeiro Luiz Arnaldo Szutan Mauricio Saab Assef Lucio Giovanni Battista Rossini 2013World Journal of Gastrointestinal Endoscopy2013,5,7:9
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