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    题名 作者 年代 出处 被引量
1土地细碎化对中国东南部水稻小农户技术效率的影响显示文摘目的水稻生产是中国广大稻区农民收入和减轻贫困的重要途径,而土地细碎化可能是目前进一步提高农业生产率和减轻农村贫困的主要瓶颈之一。方法采用详实的农户调查以及作物水平和地块层次的数据,用两阶段法分析了土地细碎化对中国东南部一个水稻主要产区农户技术效率的影响。结果研究区早稻的平均技术效率为0.85,晚稻为0.83,而单季稻为0.79。稻田平均地块大小对早、中、晚3种水稻的技术效率都有显著的正影响。此外,家庭规模和农地规模对3种水稻生产的技术效率也有显著影响。人口较多的家庭或规模较大的农场技术效率较小家庭或小农场要高。结论在现有技术状态下,水稻小农户的技术效率仍可得到可观的提高。研究揭示,减轻土地细碎度的项目如果能够与促进农村劳动力市场发育的措施结合起来,将是提高水稻生产技术效率行之有效的途径。谭淑豪 Nico Heerink 曲福田 2006中国农业科学2006,39,12:82
2China’s New Rural Income Support Policy:Impacts on Grain Production and Rural Income Inequality显示文摘This paper analyses the impact of agricultural tax abolition and direct income payments to grain farmers on grain production and rural inequality in China. To separate the impact of the income support measures from recent price trends for grains and inputs, and to account for differences in household responses, we use a village-level general equilibrium model that we calibrate for two villages with different degrees of market access in Jiangxi province. The results show that the income support policy does not reach its goal of promoting grain production. The increased incomes allow farm households to buy more inputs for livestock production and involve other activities that are more profitable than grain farming. Selling of rice outside the villages declines more than rice production, because households in the villages consume more rice when incomes rise. We further find that the income support measures tend to reduce income within a village, but that tax abolition tends to widen income inequality between villages.Nico Heerink Marijke Kuiper 2006China & World Economy2006,14,6:26
3中荷研究型大学教师工作环境观对其教学科研关系观的影响显示文摘对中国和荷兰研究型大学教师的工作环境观和教学科研关系观的调查与分析显示:中荷研究型大学教师在处理教学与科研的关系上是'观念上的结合',两国教师都在观念上认同教学与科研是相互依存、彼此加强的关系;但在教学环境观上,中国教师强调科研压力和工作量增大所带来的负面影响,而荷兰教师对工作量大小对其教学的影响基本持中立态度。当中荷教师认为其所在院系强调科研、轻视教学及科研压力过大导致其在教学上精力分配减少时,其对教学科研正相关的关系观会被弱化。吴薇 谢作栩 Nico Verloop 2010教育研究2010,31,12:16
4300名正常上前牙牙根与牙槽窝位置关系的锥形束CT分析显示文摘目的 回顾性分析正常上前牙牙根与牙槽窝位置关系的锥形束CT资料,为前牙区即刻种植适应证的选择提供解剖依据.方法 选取2013年9月至2014年8月于第四军医大学口腔医学院就诊并拍摄锥形束CT的300名正常锥形束CT资料,三维重建后调整至各前牙牙齿正中矢状面,对上颌前牙牙根与牙槽窝的位置关系进行分类,牙根偏唇侧型(B型)、牙根居中型(M型)、牙根偏腭侧型(P型);1型(牙根长轴偏向腭侧)、2型(牙根长轴偏向唇侧但未超过唇侧牙槽骨最凹点A点)、3型(牙根长轴偏向唇侧且超过A点).测量根尖至鼻底骨缘的距离(即根尖区骨高度),锥形束CT资料根据年龄分为3组:19~30岁组、31~50岁组和51~75岁组;比较不同牙位、不同年龄组、不同性别根尖区骨高度的差异.结果 中切牙、侧切牙和尖牙的根尖区骨高度分别为(9.2±3.0)、(10.0±2.9)和(8.1±3.1)mm,中切牙与侧切牙的差异无统计学意义(P〉0.05),中切牙、侧切牙与尖牙差异均有统计学意义(P〈0.05).对于同一牙位,男性与女性根尖区骨高度差异均无统计学意义(P〉0.05).31~50岁组、51~75岁组上前牙各牙位根尖区骨高度均显著大于19~30岁组(P〈0.05).上前牙牙根矢状向位置分类B、P、M型占比分别为98.5%(1774/1800)、0.3%(5/1800)、1.2%(21/1800),1、2、3型占比分别为2.6%(46/1800)、58.6%(1055/1800)、38.8%(699/1800).结论 正常上前牙根尖区常有较充足的骨高度,但牙齿正中矢状面上牙根大多偏向牙槽窝唇侧.陶荣 蒙萌 牛丽娜 陈吉华 Nico H. J. Creugers 马楚凡 2017中华口腔医学杂志2017,52,10:12
5牙列缺损的功能分类与牙齿磨耗相关性的临床调查研究显示文摘目的:调查研究牙齿磨耗与牙列缺损的关系及牙齿磨耗的影响因素,为牙齿磨耗的预防与治疗提供依据。方法:通过问卷调查和临床检查收集数据,结合牙科功能等级分类系统,采用Smith和Knight牙齿磨耗指数TWI对257名修复患者5 930个牙的磨耗程度进行检查,通过多元线性回归分析及t检验分析牙齿磨耗与牙列缺损之间的关系,以揭示影响牙齿磨耗的相关因素。结果:经多元线性回归分析,在上下颌有≥10个牙的牙列中,前牙、前磨牙功能面磨耗程度显著低于上下颌<10个牙的牙列(P<0.05,B<0),磨牙的功能面磨耗无显著差异;在双侧磨牙区至少有1个咬合对数的牙列中,前磨牙功能面磨耗显著低于双侧磨牙区无咬合对数的牙列(P<0.05,B<0)。t检验结果显示,男性患者磨牙功能面磨耗的均数显著高于女性(P<0.05),而前牙与前磨牙功能面磨耗的均数比较无显著性差异(P>0.05)。结论:牙齿磨耗与口内余留牙数目及咬合对数密切相关,男性牙齿磨耗比女性严重。蒙萌 李冬梅 马楚凡 张少锋 张倩 Nico H.J.Creugers 2013牙体牙髓牙周病学杂志2013,23,2:12
6正规、非正规借贷对农户支出总量及其结构的影响显示文摘刺激农村居民消费是当前我国发展的主要任务之一,正规与非正规金融的发展是否显著影响农户的支出总量及其结构需要实证的检验。与以往研究结论不同,本文考虑了融资需求,重新定义信贷约束,使用2011年中国家庭金融调查数据检验发现,正规金融显著提高了农户的支出总量。相反,民间借贷的作用并不显著。进一步分析得知,正规贷款通过增加农业生产投入,降低储蓄的持有度,不仅提高了农户的食品消费,而且提高了教育投资,进而拉动了支出总量。然而,生产性的民间借贷和非生产性借贷对农业投资存在相互抵消作用,使得家庭总体民间借贷对消费影响不显著。徐丽鹤 Nico Heerink 2015农业技术经济2015,,3:12
7乙型肝炎病毒导致的肝硬化伴肝癌患者血清中N糖组学改变显示文摘肝细胞癌(HCC)是最常见的肿瘤和最主要的死因之一,多发生于HBV和HCV感染导致的肝硬化患者,筛查肝硬化人群,早期诊断HCC可降低肿瘤的病死率。甲胎蛋白(AFP)是目前广泛应用的辅助诊断HCC的血清学指标,是对B超、CT等影像学诊断的有效补充。最近的荟萃分析表明,不同研究论文报道的AFP的灵敏度和特异度有很大的不同,这种现象不能完全用AFP的临界值不同解释。血清中的N糖蛋白主要由肝脏和B淋巴细胞合成,N糖成分的改变可反应肝脏或B淋巴细胞功能的改变,糖链的改变常常反应出机体的异常改变。糖组学在诊断领域的应用曾经因为缺少合适的分析技术而受限制,血清中N糖组学分析技术克服了这一屏障。本研究的目的是评价血清中N糖指纹图谱应用于乙型肝炎后肝硬化伴肝癌辅助诊断的意义。刘学恩 Liesbeth Desmyter 高春芳 Wouter Laroy Sylviane Dewaele Valerie Vanhooren 王玲 庄辉 Nico Callewaert Claude Libert Roland Contreras 陈翠英 2008中华肝脏病杂志2008,16,1:11
8荧光原位杂交法对血培养标本中细菌和真菌鉴定效果评价显示文摘目的 建立一种阳性血培养标本的检测和鉴定的快速方法。方法 采用荧光原位杂交法 ,Bact/Alert仪器报警后 ,取阳性血培养液 15 μl于玻片上 ,全细胞杂交 1h ,同时将阳性标本转种培养基平板 ,用VITEK仪器法鉴定 ,比较杂交法与仪器法的符合率。结果 杂交法与仪器法测定了 118份临床阳性标本 ,葡萄球菌属的符合率96 3% ,链球菌属和肠球菌属的符合率 10 0 % ,革兰阴性杆菌的符合率 86 8% ,白色念珠菌的符合率 10 0 % ,总符合率 91 5 %。结论 联合应用Bact/Alert血培养仪及荧光原位杂交法 ,能显著缩短阳性血培养标本中的细菌和真菌的鉴定时间。王沛 Gjalt.W.WELLING Nico MEESSEN 2004中华医院感染学杂志2004,14,2:11
9农村市场发育与村庄经济研究显示文摘近年来随着农村改革的不断深入以及农户非农就业的增加 ,农村要素市场和产品市场已逐渐出现。当农户之间的市场交换活动发生在村庄内或一个小区域之内时 ,农户之间的市场交换就会使农户之间产生很强的市场联系 ,一部分农户的生产、消费决策行为的变化就和另一部分农户行为的变化紧密联系起来 ,政策变化对农户的影响就要考虑农户之间的这种联系 ,这时就适用村庄经济的研究方法如村庄社会核算矩阵乘数模型、一般均衡模型等方法。本文通过对三个村的要素市场和产品市场的分析发现 ,农村土地租赁、农业劳动力、借贷市场已经相当发育 ,农户之间由于这些市场的存在而产生了紧密的联系 ,其他要素和产品市场也在一定程度上得到发育 ,但由于主要是外向性以及农户较少参与其中而对农户之间的联系影响较弱 ,但三个市场农户的参与以及市场紧密的联系已经为应用村庄经济研究方法提供了充分的证据。石晓平 曲福田 Nico Heerink Marijke Kuiper 2004中国农村观察2004,,1:9
10Narrow-band imaging endoscopy to assess mucosal angiogenesis in inflammatory bowel disease: A pilot study显示文摘AIM: To investigate whether narrow band imaging (NBI) is a useful tool for the in vivo detection of angiogenesis in inflammatory bowel disease (IBD) patients. METHODS: Conventional and NBI colonoscopy was performed in 14 patients with colonic inflammation (8 ulcerative colitis and 6 Crohn’s disease). Biopsy samples were taken and CD31 expression was assayed immuno- histochemically; microvascular density was assessed by vessel count. RESULTS: In areas that were endoscopically normal but positive on NBI, there was a significant (P < 0.05) increase in angiogenesis (12 ± 1 vessels/field vs 18 ± 2 vessels/field) compared with areas negative on NBI. In addition, in areas that were inflamed on white light endoscopy and positive on NBI, there was a significant (P < 0.01) increase in vessel density (24 ± 7 vessels/f ield) compared with NBI-negative areas.CONCLUSION: NBI may allow in vivo imaging of intestinal angiogenesis in IBD patients.Silvio Danese Gionata Fiorino Erika Angelucci Stefania Vetrano Nico Pagano Giacomo Rando Antonino Spinelli Alberto Malesci Alessandro Repici 2010World Journal of Gastroenterology2010,16,19:9
11Molecular mechanisms of heavy metal tolerance and evolution in invertebrates显示文摘跟随基因组学革命,我们对应力位于防卫下面的分子的机制的知识极大地被扩展了。在强壮的选择压力下面,许多动物可以发展提高的应力忍耐。这能被改变蛋白质的结构完成(通过在基因的编码区域的变化) 或由改变蛋白质的数量(通过在 transcriptional 的变化规定) 。进化的后者类型能被替换在兴趣(cis 规章的变化) 或由改变 transcriptional 管理者蛋白质(trans 规章的变化) 的结构或数量的基因的倡导者完成。metallothionein 系统是在重金属的上下文的最好学习的压力反应系统之一。Metallothionein 表示被假定被金属抄写因素 1 调整(MTF-1 ) ;然而,直到现在, MTF-1 的参与仅仅为一些脊椎动物和果蝇被证明了。象线虫和蚯蚓那样的无脊椎动物上的数据建议 metallothionein 正式就职的另外的机制可能是在场的。Cd 忍耐的详细研究为土壤生活跳虫的种被做, Orchesella cincta。种类是完了的这的 metallothionein 基因在暴露金属的领域人口表示了。metallothionein 倡导者的分析表明了有功能的意义,出现在简历记者试金的广泛的多型性。在比较 20 张不同人口的研究,高快车的倡导者等位基因的频率断然在土壤与金属的集中被相关,特别 Cd。跳虫学习证明涉及细胞的应力反应的基因的那个 cis 规章的变化可以贡献金属公差的进化。Thierry K. S. Janssens Dick Roelofs Nico M. van Straalen 2009Insect Science2009,16,1:9
12基于鱼群算法的极限学习机影像分类方法优化显示文摘在传统极限学习机(ELM)研究的基础上,考虑到传统ELM参数的不确定会导致整体分类精度下降,利用仿生鱼群算法(AF)对ELM的小波核参数和正则化参数进行寻优,并构造参数优化后的小波ELM影像分类模型(AF-ELM)。通过实验比较了该算法与人工神经网路(ANN)、支持向量机(SVM)、极限学习机(ELM)等标准分类器在遥感影像分类上的精度与速度差异,并且与ELM多项式核、RBF核分类算法进行比较分析,验证了AF-ELM在分类速度和精度上的优越性。实验结果表明,AF-ELM分类方法分类速度较快,精度较高,均优于其他分类方法。能较好地应用于遥感影像上各类地物要素的自动提取。林怡 季昊巍 NICO Sneeuw 叶勤 2017农业机械学报2017,48,10:8
13Outcome of stenting in biliary and pancreatic benign and malignant diseases:A comprehensive review显示文摘Endoscopic stenting has become a widely method for the management of various malignant and benign pancreatico-biliary disorders. Biliary and pancreatic stents are devices made of plastic or metal used primarily to establish patency of an obstructed bile or pancreatic duct and may also be used to treat biliary or pancreatic leaks,pancreatic fluid collections and to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis. In this review,relevant literature search and expert opinions have been used to evaluate the outcome of stenting in biliary and pancreatic benign and malignant diseases.Benedetto Mangiavillano Nico Pagano Todd H Baron Carmelo Luigiano 2015World Journal of Gastroenterology2015,21,30:8
14高寒冰雪覆盖型和湿润亚热带型岩溶水系统碳汇强度对比显示文摘以岩性相近但气候和土地利用迥异的两个具有高分辨率水文水化学自动监测数据的岩溶水系统——湿润亚热带以土质坡地为主的岩溶水系统(贵州普定后寨岩溶水系统)和高寒冰雪覆盖下以石质坡地为主的岩溶水系统(瑞士阿尔卑斯山区的Tsanfleuron冰川岩溶水系统)作为研究对象,进行岩溶作用碳汇强度对比研究。结果发现,后寨岩溶水系统的[HCO3-]年均值为222mg/L,而Tsanfleuron冰川岩溶水系统的[HCO3-]年均值仅为131mg/L,表明湿润亚热带岩溶水系统具有较高的[HCO3-]特征。然而,湿润亚热带岩溶水系统的碳汇强度(60.82t/(km2·a))与Tsanfleuron冰川岩溶水系统的碳汇强度(59.06t/(km2·a))相当。冰川岩溶水系统同样具有较高岩溶作用碳汇强度的原因主要是在全球变暖的背景下,冰川退缩加剧,冰川固体水库水量释放增多,致使冰川岩溶水系统径流量显著增加效应超出因稀释作用而产生的[HCO3-]降低效应,进而使得山岳冰川岩溶水系统的碳汇强度增大。这也暗示着随着某些冰川融化,径流量逐渐减小将使岩溶作用碳汇强度降低。曾成 赵敏 杨睿 刘再华 Vivian Gremaud Nico Goldscheider 2011气候变化研究进展2011,7,3:7
15Experimental Basis of Determining Maximum Coronary, Myocardial, and Collateral Blood Flow by Pressure Measurements for Assessing Functional Stenosis Severity Before and After Percutaneous Transluminal Coronary Angioplasty显示文摘Nico H.J. Pijls Jacques A.M. van Son Richard L. Kirkeeide Bernard De Bruyne Lance K. Gould 1993Circulation1993,,4:6
16Biliary and pancreatic stenting:Devices and insertiontechniques in therapeutic endoscopic retrogradecholangiopancreatography and endoscopic ultrasonography显示文摘Stents are tubular devices made of plastic or metal. Endoscopic stenting is the most common treatment for obstruction of the common bile duct or of the main pancreatic duct, but also employed for the treatment of bilio-pancreatic leakages, for preventing post- endoscopic retrograde cholangiopancreatography pancreatitis and to drain the gallbladder and pancreatic fluid collections. Recent progresses in techniques of stent insertion and metal stent design are represented by new, fullycovered lumen apposing metal stents. These stents are specifically designed for transmural drainage, with a saddle-shape design and bilateral flanges, to provide lumen-to-lumen anchoring, reducing the risk of migration and leakage. This review is an update of the technique of stent insertion and metal stent deployment, of the most recent data available on stent types and characteristics and the new applications for biliopancreatic stents.Benedetto Mangiavillano Nico Pagano Todd H Baron Monica Arena Giuseppe Iabichino Pierluigi Consolo Enrico Opocher Carmelo Luigiano 2016World Journal of Gastrointestinal Endoscopy2016,8,3:6
17Tree diversity and nectar composition affect arthropod visitors on extrafloral nectaries in a diversity experiment显示文摘Aims Plants with extrafloral nectaries(EFNs)are common in tropical and subtropical habitats and,despite many other arthropods also forage for EFN,most studies solely focused on the defense mutualisms between EFN plants and ants.This study aims at a quantitative assessment of the entire arthropod community that visits EFN trees to compare visitor communities between different tree species to disentangle the mechanisms that may drive EFN visitor community composition.We also test for tree diversity effects on EFN visitors,as it is unknown if local tree species richness relates to the abundance and species richness of arthropods foraging for EFN.Methods We sampled EFN-visiting arthropods in the experimental tree species richness gradient of the BEF-China Experiment,the currently largest forest diversity experiment in the world,and tested if tree species richness affects EFN visitors and if visitor community composition differs between EFN tree species.In a second step,we analyzed the EFN of Ailanthus altissima and Triadica cochinchinensis,the two EFN tree species with highest visitor abundance,for sugars and amino acids(AA)to test if tree species-specific differences in nectar chemistry translate to differing visitor communities.Lastly,we conducted a choice experiment using different artificial nectar solutions to test if nectar quality affects foraging decisions of ants,the most frequent EFN visitors in our study sites.Important Findings EFN trees in young successional forests in subtropical South-East China are visited by a diverse assemblage of arthropods including ants,beetles,flies,and spiders.Albeit ants accounted for about 75%of all individuals,non-ant visitors were by far more species rich.Visitor abundance and species richness declined with increasing tree species richness,suggesting a resource dilution effect,because plots with more tree species had proportionally less EFN tree individuals and thus lower nectar availability.Ailanthus altissima and T.cochinchinensis were visited by different arthropods and their nectar had species-specific AA composition and sugar concentration,indicating that differences in visitors may,at least partly,be explained by differences in nectar chemistry.These findings are supported by the choice experiment,in which artificial nectars containing sugar solutions supplemented with essential AAs attracted more ants than pure sugar solutions or sugar solutions supplemented with non-essential AAs.Our results improve the understanding of the complex ecology of EFN trees,a plant life form that might be crucial for understanding how tree diversity influences patterns of tree growth in young successional tropical and subtropical forests.Michael Staab Joel Methorst Jan Peters Nico Blüthgen Alexandra-Maria Klein 2017Journal of Plant Ecology2017,10,1:6
18Reconsidering research on teachers’ professional identity显示文摘Douwe Beijaard Paulien C. Meijer Nico Verloop 2004Teaching and Teacher Education2004,,2:5
19The role of K- ras gene mutation analysis in EUS-guided FNA cytology specimens for the differential diagnosis of pancreatic solid masses: a meta-analysis of prospective studies显示文摘Lorenzo Fuccio Cesare Hassan Liboria Laterza Loredana Correale Nico Pagano Paolo Bocus Carlo Fabbri Antonella Maimone Vincenzo Cennamo Alessandro Repici Guido Costamagna Franco Bazzoli Alberto Larghi 2013Gastrointestinal Endoscopy2013,,:4
20布鲁氏菌引起的巨噬细胞依赖性树突状细胞迁移与免疫应答显示文摘目的:研究阴道巨噬细胞清除后小鼠对布鲁氏菌疫苗的免疫应答机制。方法:BALB/c小鼠60只随机分为3组,每组20只,实验组小鼠阴道内滴注脂质体包裹的clodronate以清除阴道巨噬细胞,3d后阴道滴注10μL布鲁氏菌疫苗(含6×108个布鲁氏菌)。同时设空脂质体对照组(不含clo-dronate)和PBS对照组。依次在12、24、36、72h收集小鼠阴道、髂内淋巴结和血液。采用免疫组织化学染色法观察阴道巨噬细胞清除效果和树突状细胞(DC)的迁移,并用ELISA法检测血清中IFN-γ和IL-4的含量。收集小鼠腹腔液制备巨噬细胞进行细胞培养,1.2×106个巨噬细胞中加入布鲁氏菌疫苗10μL,于不同时间点对巨噬细胞进行姬姆萨染色,观察巨噬细胞的变化。结果:清除巨噬细胞组小鼠接种布鲁氏菌疫苗后,髂内淋巴结中S-100阳性DC数量没有明显的变化,IFN-γ和IL-4的含量也没有明显的升高。非清除组中,不同的时间点,髂内淋巴结中S-100阳性DC明显增多,与PBS对照组相比,IFN-γ含量显著增高,而IL-4则没有明显变化。体外巨噬细胞负载布鲁氏菌疫苗发现,随着时间的延长,巨噬细胞吞噬布鲁氏菌逐渐增多,在12h,巨噬细胞开始出现坏死性凋亡。结论:小鼠在对布鲁氏菌疫苗的免疫应答中,DC的迁移是巨噬细胞依赖性的,并且这种依赖性有可能是由布鲁氏菌抗原成分在细胞间间接传递引起的。韩丽滨 董炳梅 李妍 何媛娜 Nico van Rooijen 王少华 付景丽 王家鑫 2009细胞与分子免疫学杂志2009,25,6:3
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