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| 1 | Liver-specific gene expression in mesenchymal stem cells is induced by liver cells显示文摘AIM: The origin of putative liver cells from distinct bone marrow stem cells, e.g. hematopoietic stem cells or multipotent adult progenitor cells was found in recent in vitro studies. Cell culture experiments revealed a key role of growth factors for the induction of liver-specific genes in stem cell cultures. We investigated the potential of rat mesenchymal stem cells (MSC) from bone marrow to differentiate into hepatocytic cells in vitro. Furthermore,we assessed the influence of cocultured liver cells on induction of liver-specific gene expression.METHODS: Mesenchymal stem cells were marked with green fluorescent protein (GFP) by retroviral gene transduction. Clonal marked MSC were either cultured under liver stimulating conditions using fibronectin-coated culture dishes and medium supplemented with SCF, HGF,EGF, and FGF-4 alone, or in presence of freshly isolated rat liver cells. Cells in cocultures were harvested and GFP+ or GFP- cells were separated using fluorescence activated cell sorting. RT-PCR analysis for the stem cell marker Thy1 and the hepatocytic markers CK-18, albumin, CK-19,and AFP was performed in the different cell populations.RESULTS: Under the specified culture conditions, rat MSC cocultured with liver cells expressed albumin-, CK-18,CK-19, and AFP-RNA over 3 weeks, whereas MSC cultured alone did not show liver specific gene expression.CONCLUSION: The results indicate that (1) rat MSC from bone marrow can differentiate towards hepatocytic lineage in vitro, and (2) that the microenvironment plays a decisive role for the induction of hepatic differentiation of rMSC. | Claudia Lange Philipp Bassler Michael V. Lioznov Helge Bruns Dietrich Kluth Axel R. Zander Henning C. Fiegel | 2005 | World Journal of Gastroenterology2005,11,29: | 31 |
| 2 | 北大西洋年际变率的海气耦合模式模拟Ⅰ局地海气相互作用显示文摘检验了一个全球海气耦合模式对北大西洋年际气候变率的模拟,讨论了导致这种年际变率型的物理机制,并分析了其对年代际变率的可能影响。北大西洋冬季SST的主导变率模态,在经向上表现为三核型,自北而南出现“-+-”的带状距平型;最大距平中心位于副极地大洋、中纬度大洋的西部以及热带海域,耦合模式较为真实地再现了这一特征。与三核型SST异常相对应的大气环流型表现为北大西洋涛动,具有显著的正压结构。上述异常型主要发生在年际尺度,具有3—4年的谱峰;在次年代际尺度上,也存在谱峰。分析表明,模式中三核型SST异常的产生,主要来自大气的强迫,NAO增强,中纬度大洋上的西风减弱,海洋感热和潜热通量损失减少,中纬度大洋得到的净热通量增加,导致SST出现正距平;在包括Labrador海在内的副极地大洋,NAO增强、冰岛低压加深,气旋性环流增强,来自高纬度的冷空气吹过洋面,海气温差加大,大洋的感热通量损失增加,SST降低。热带地区东风的增强,也是导致那里SST降低的重要机制。三核型SST异常对大气的反馈作用较弱,文中没有证据表明它能够影响到北大西洋地区的年代际气候变率。 | 周天军 宇如聪 郜永祺 Helge Drange | 2006 | 气象学报2006,64,1: | 27 |
| 3 | Hepatocytic differentiation of mesenchymal stem cells in cocultures with fetal liver cells显示文摘瞄准:为了与胎儿的肝细胞(FLC ) 和可能性在合作文化调查间充质的干细胞(MSC ) 的 hepatocytic 区别膨胀,区分了 hepatocytic 房间。方法:MSC 被制动火箭与绿荧光灯的蛋白质(GFP ) 标记病毒的基因转导变异。同种细胞的显著 MSC 在用与干细胞补充的fibronectin涂的培养皿和媒介刺激条件的肝下面是也有教养的因素( SCF ), hepatocyte 生长因素( HGF ),表皮的生长因素( EGF ),和成纤维细胞生长因素 4 ( FGF-4 )独自一个,或在刚孤立的 FLC 的存在。在合作文化的房间被收获,并且 GFP+ 或 GFP- 房间用荧光被分开激活的房间排序。为肝 specific 标记 cytokeratin-18 (CK-18 ) 的反向的抄写聚合酶链反应(RT-PCR )( 法新社) ,白朊,和 alpha-fetoprotein 在不同房间人口被执行。结果:在指定文化条件下面,与 FLC co 有教养的老鼠 MSC 超过二个星期表示了白朊, CK-18,和 AFP-RNA。在 wk 3, MSC 失去了 hepatocytic 基因表示,可能由于 cocultured FLC 的增生。FLC 也在合作文化和一个很高的生长潜力显示出稳定的肝 specific 基因表情。结论:从骨髓的老鼠 MSC 能面对 FLC 在试管内区分 hepatocytic 房间,在合作文化的 MSC 的存在也为 FLC 的扩大和区别提供有益的环境。 | Claudia Lange Helge Bruns Dietrich Kluth Axel R Zander Henning C Fiegel | 2006 | World Journal of Gastroenterology2006,12,15: | 23 |
| 4 | Contrast-enhanced and targeted ultrasound显示文摘Ultrasonic imaging is becoming the most popular medical imaging modality,owing to the low price per examination and its safety.However,blood is a poor scatterer of ultrasound waves at clinical diagnostic transmit frequencies.For perfusion imaging,markers have been designed to enhance the contrast in B-mode imaging.These so-called ultrasound contrast agents consist of microscopically small gas bubbles encapsulated in biodegradable shells.In this review,the physical principles of ultrasound contrast agent microbubble behavior and their adjustment for drug delivery including sonoporation are described.Furthermore,an outline of clinical imaging applications of contrast-enhanced ultrasound is given.It is a challenging task to quantify and predict which bubble phenomenon occurs under which acoustic condition,and how these phenomena may be utilized in ultrasonic imaging.Aided by high-speed photography,our improved understanding of encapsulated microbubble behavior will lead to more sophisticated detection and delivery techniques.More sophisticated methods use quantitative approaches to measure the amount and the time course of bolus or reperfusion curves,and have shown great promise in revealing effective tumor responses to anti-angiogenic drugs in humans before tumor shrinkage occurs.These are beginning to be accepted into clinical practice.In the long term,targeted microbubbles for molecular imaging and eventually for directed anti-tumor therapy are expected to be tested. | Michiel Postema Odd Helge Gilja | 2011 | World Journal of Gastroenterology2011,17,1: | 22 |
| 5 | On the combined effect of soil fertility and topography on tree growth in subtropical forest ecosystems—a study from SE China显示文摘Aims The aim of our research was to understand small-scale effects of topography and soil fertility on tree growth in a forest biodiversity and ecosystem functioning(BEF)experiment in subtropical SE China.Methods Geomorphometric terrain analyses were carried out at a spatial resolution of 5×5 m.Soil samples of different depth increments and data on tree height were collected from a total of 566 plots(667 m2 each).The soils were analyzed for carbon(soil organic carbon[SOC]),nitrogen,acidity,cation exchange capacity(CEC),exchangeable cations and base saturation as soil fertility attributes.All plots were classified into geomorphological units.Analyses of variance and linear regressions were applied to all terrain,soil fertility and tree growth attributes.Important Findings In general,young and shallow soils and relatively small differences in stable soil properties suggest that soil erosion has truncated the soils to a large extent over the whole area of the experiment.This explains the concurrently increasing CEC and SOC stocks downslope,in hollows and in valleys.However,colluvial,carbon-rich sediments are missing widely due to the convexity of the footslopes caused by uplift and removal of eroded sediments by adjacent waterways.The results showed that soil fertility is mainly influenced by topography.Monte-Carlo flow accumulation(MCCA),curvature,slope and aspect significantly affected soil fertility.Furthermore,soil fertility was affected by the different geomorphological positions on the experimental sites with ridge and spur positions showing lower exchangeable base cation contents,especially potassium(K),due to leaching.This geomorphological effect of soil fertility is most pronounced in the topsoil and decreases when considering the subsoil down to 50 cm depth.Few soil fertility attributes affect tree height after 1-2 years of growth,among which C stocks proved to be most important while pH_(KCl)and CEC only played minor roles.Nevertheless,soil acidity and a high proportion of Al on the exchange complex affected tree height even after only 1-2 years growth.Hence,our study showed that forest nutrition is coupled to a recycling of litter nutrients,and does not only depend on subsequent supply of nutrients from the mineral soil.Besides soil fertility,topography affected tree height.We found that especially MCCA as indicator of water availability affected tree growth at small-scale,as well as aspect.Overall,our synthesis on the interrelation between fertility,topography and tree growth in a subtropical forest ecosystem in SE China showed that topographic heterogeneity lead to ecological gradients across geomorphological positions.In this respect,small-scale soil-plant interactions in a young forest can serve as a driver for the future development of vegetation and biodiversity control on soil fertility.In addition,it shows that terrain attributes should be accounted for in ecological research. | Thomas Scholten Philipp Goebes Peter Kühn Steffen Seitz Thorsten Assmann Jürgen Bauhus Helge Bruelheide Francois Buscot Alexandra Erfmeier Markus Fischer Werner Härdtle Jin-Sheng He Keping Ma Pascal A.Niklaus Michael Scherer-Lorenzen Bernhard Schmid Xuezheng Shi Zhengshan Song Goddert von Oheimb Christian Wirth Tesfaye Wubet Karsten Schmidt | 2017 | Journal of Plant Ecology2017,10,1: | 22 |
| 6 | 卑尔根气候模式中大西洋热盐环流年代际与年际变率的气候影响显示文摘利用一个全球海气耦合模式———卑尔根气候模式的积分结果 ,揭示了与大西洋热盐环流 (THC)年代际和年际振荡相对应的气候异常型。年代际振荡发生在全海盆尺度 ,伴有亚速尔高压的增强、冰岛低压的加深 ;年际振荡发生在局地尺度 ,伴有亚速尔高压的减弱。这两种海平面气压异常型都反映了北大西洋涛动 (NAO)活动中心的强度变化 ,两种变率型对应的拉布拉多海对流活动都加剧。但伴随局地尺度的THC调整 ,伊尔明格海的对流活动减弱。蒸发异常对拉布拉多海表层盐度异常的影响较为显著。分析表明 ,局地尺度的THC振荡主要是对大气强迫的被动响应 ,而海盆尺度THC振荡的实质是反映整个输送带的强度变化 ,其气候意义要大于THC的局地振荡。 | 周天军 Helge DRANGE | 2005 | 大气科学2005,29,2: | 21 |
| 7 | Crown and leaf traits as predictors of subtropical tree sapling growth rates显示文摘Aims Growth rates of plants are driven by factors that influence the amount of resources captured and the efficiency of resource use.In trees,the amount of light captured and the efficiency of light use strongly depends on crown characteristics and leaf traits.Although theory predicts that both crown and leaf traits affect tree growth,few studies have yet to integrate these two types of traits to explain species-specific growth rates.Using 37 broad-leaved tree species of subtropical forests in SE China,we investigated how interspecific differences in wood volume growth rates were affected by crown and leaf traits.We tested the hypotheses that(i)larger crown dimensions promote growth rates,(ii)species-specific growth rates are positively related to leaf stomatal conductance,leaf water potential and leaf chemical components,and negatively related to leaf C/N and leaf toughness and(iii)the two sets of traits better explain growth rates in combination than either alone.Methods Our study was conducted in a large-scale forest Biodiversity and Ecosystem Functioning experiment in China(BEF-China),located in a mountainous region in Jiangxi Province.We related 17 functional traits(two crown dimension and three crown structure traits;six physiological and six morphological leaf traits)to the mean annual growth rate of wood volume of young trees of the studied species.Interrelationships between crown and leaf traits were analyzed using principal component analysis.Simple linear regression analysis was used to test the effect of each trait separately.We used multiple regression analysis to establish the relationship of growth rate to each set of traits(crown traits,physiological and morphological leaf traits)and to the combination of all types of traits.The coefficients of determination(R^(2)_(adj))of the best multiple regression models were compared to determine the relative explanatory power of crown and leaf traits and a combination of both.Important Findings The species-specific growth rates were not related to any of the single crown traits,but were related positively to leaf stomatal conductance and leaf water potential individually,and negatively to leaf toughness,with approximately 13%variance explained by each of the traits.Combinations of different crown traits did not significantly explain the species-specific growth rates,whereas combinations of either physiological or morphological leaf traits explained 24%and 31%,respectively.A combination of both crown and leaf traits explained 42%of variance in species-specific growth rates.We concluded that sets of traits related to carbon assimilation at the leaf-level and to overall amount of leaves exposed at the crown-level jointly explained species-specific growth rates better than either set of traits alone. | Ying Li Wenzel Kröber Helge Bruelheide Werner Härdtle Goddert von Oheimb | 2017 | Journal of Plant Ecology2017,10,1: | 18 |
| 8 | Interspecific and intraspecific variation in specific root length drives aboveground biodiversity effects in young experimental forest stands显示文摘Aims Although the net biodiversity effect(NE)can be statistically partitioned into complementarity and selection effects(CE and SE),there are different underlying mechanisms that can cause a certain partitioning.Our objective was to assess the role of resource partitioning and species interactions as two important mechanisms that can bring about CEs by interspecific and intraspecific trait variation.Methods We measured tree height of 2493 living individuals in 57 plots and specific root length(SRL)on first-order roots of 368 of these individuals across different species richness levels(1,2,4,8 species)in a large-scale forest biodiversity and ecosystem functioning experiment in subtropical China(BEF-China)established in 2009.We describe the effects of resource partitioning between species by a fixed component of interspecific functional diversity(RaoQ)and further effects of species interactions by variable components of interspecific and intraspecific functional diversity(community weighted trait similarity and trait dissimilarity,CWS and CWD).Finally,we examined the relationships between biodiversity effects on stand-level tree height and functional diversity(RaoQ,CWS and CWD)in SRL using linear regression and assessed the relative importance of these three components of functional diversity in explaining the diversity effects.Important Findings Our results show that species richness significantly affected SRL in five and tree height in ten out of 16 species.A positive NE was generally brought about by a positive CE on stand-level tree height and related to high values of RaoQ and CWS in SRL.A positive CE was related to high values of all three components of root functional diversity(RaoQ,CWS and CWD).Our study suggests that both resource partitioning and species interactions are the underlying mechanisms of biodiversity effects on stand-level tree growth in subtropical forest. | Wensheng Bu Bernhard Schmid Xiaojuan Liu Ying Li Werner Härdtle Goddert von Oheimb Yu Liang Zhenkai Sun Yuanyuan Huang Helge Bruelheide Keping Ma | 2017 | Journal of Plant Ecology2017,10,1: | 18 |
| 9 | 上海26万妇女乳房自我检查随机试验显示文摘目的论证指导妇女进行乳房自我检查(BSE)是否能有效降低乳腺癌患者的死亡率。方法自1989年10月起,上海26.6万名年龄在30~64岁的妇女,随机进入指导组(132979名)和对照组(133085名)。在指导组,最初先由医务人员做规范的BSE手法演示,随后的4年中,使用BSE录像带进行二次强化教育,并定期进行BSE指导和在医务人员监察下进行BSE操作。本研究进行5年,全部活动均被记录。队列人群随访到2000年7月,乳腺癌患者的生存状况随访到2001年12月。统计分析采用Kaplan-Meier方法、Logrank检验以及Cox模型。结果指导组检出乳腺癌864例,其中死于乳腺癌133例;对照组检出乳腺癌896例,其中死于乳腺癌130例。两组乳腺癌病例的肿块大小、TNM分期和累积死亡率的差异均无统计学意义(P均>0.05)。但是指导组比对照组有较多和较小的纤维腺瘤被检出(P<0.01)。结论对人群开展BSE教育和指导,未能降低人群的乳腺癌死亡率;接受BSE教育的妇女比没有接受教育的妇女可检出较多的和较小的良性乳房肿块。 | 高道利 David BThomas Roberta M Ray 王文婉 Charlene J Allison 陈范良 Peggy Porter 胡永伟 赵关林 潘雷达 李雯瑾 武春园 Zakia Coriaty Ilonka Evans 林明纲 Helge Stalsberg Steven Gself | 2005 | 中华肿瘤杂志2005,27,6: | 14 |
| 10 | 北大西洋年际变率的海气耦合模式模拟II:热带太平洋强迫显示文摘利用一个全球海气耦合模式(BCM),结合观测资料,讨论了热带太平洋强迫对北大西洋年际气候变率的影响。研究表明,BCM能够相对合理地模拟赤道太平洋的年际变率模态及相应的海温距平型和大气遥相关型,尽管其准3年的振荡周期过于规则。来自数值模式和观测上的证据都表明,北大西洋冬季海温的主导性变率模态,即自北而南出现的“-+-”的海温距平型,受到来自热带太平洋强迫的显著影响,其正位相与赤道中东太平洋冷事件相对应。换言之,赤道太平洋暖事件的发生,在太平洋-北美沿岸激发出PNA遥相关型,进而通过在北大西洋产生类似NAO负位相的气压距平型,削弱本来与NAO正位相直接联系的三核型海温距平。北大西洋三核型海温距平对热带太平洋强迫的响应,要滞后2—3个月的时间。 | 周天军 宇如聪 郜永祺 Helge Drange | 2006 | 气象学报2006,64,1: | 14 |
| 11 | Positive effects of tree species richness on fine-root production in a subtropical forest in SE-China显示文摘Aims Fine roots play an important role in the biogeochemical cycles of terrestrial ecosystems and are vital for understanding forest ecosystem functioning and services.Higher plant species diversity has been largely reported to increase aboveground community biomass,but how biodiversity affects fine-root production and the related mechanisms in forests remain unclear.In this study,we aim to answer two questions:(i)does fine-root production increase with tree species richness?(ii)Can this effect be explained by niche complementarity among species?Methods We analyzed data from a large forest biodiversity experiment(BEF-China)with 5-year-old trees.Fine-root growth was measured as standing biomass and annual fine-root regrowth was estimated using ingrowth cores.Moreover,relative yield was calculated to test whether over-or under-yielding occurred when mixtures were compared with the average monoculture of the species included in the mixtures.We calculated functional diversity for fine-root(≤2 mm in diameter)traits by Rao’s quadratic entropy index for each species mixture.The effects of manipulated tree species richness and identity on fine-root traits were analyzed with linear mixed-effects models.Mixed models were also used to test the relationships between tree species richness and fine-root standing biomass,annual regrowth and vertical heterogeneity.Important Findings Fine roots of more than one species were found in half of the soil cores in mixtures indicating that belowground interactions in these young forest stands occurred much earlier than canopy closure.We found significant differences among species in fine-root traits such as diameter and specific root length(SRL),which suggested different resource-use strategies and niche partitioning among species.Mean fine-root diameter of species ranged from 0.31 to 0.74 mm,mean SRL ranged from 12.43 m·g^(−1)to 70.22 m·g^(−1)and mean vertical distribution indexβranged from 0.68 to 0.93.There was a significant positive relationship between species richness and the evenness of the vertical distribution of fine-root standing biomass.Moreover,marginally significant positive relationships existed between species richness and standing biomass as well as annual regrowth of fine roots.Relative yields and Rao’s quadratic entropy index were both not significantly affected by species richness.However,the relative yield of fine-root standing biomass was marginally correlated with Rao’s quadratic entropy index,implying that belowground niche complementarity between species does contribute to diversity effects.In conclusion,our study showed positive effects of species richness on the filling of soil volume by fine roots in the studied experimental forest communities.This has positive effects on fine-root standing biomass and may also lead to increased aboveground biomass. | Zhenkai Sun Xiaojuan Liu Bernhard Schmid Helge Bruelheide Wensheng Bu Keping Ma | 2017 | Journal of Plant Ecology2017,10,1: | 14 |
| 12 | Sensitivity of East Asian Climate to the Progressive Uplift and Expansion of the Tibetan Plateau Under the Mid-Pliocene Boundary Conditions显示文摘A global atmospheric general circulation model has been used to perform eleven idealized numerical experiments, i.e., TP00, TP10, ···, TP100, corresponding to different percentages of the Tibetan Plateau altitude. The aim is to explore the sensitivity of East Asian climate to the uplift and expansion of the Tibetan Plateau under the reconstructed boundary conditions for the mid-Pliocene about 3 Ma ago. When the plateau is progressively uplifted, global annual surface temperature is gradually declined and statistically significant cooling signals emerge only in the Northern Hemisphere, especially over and around the Tibetan Plateau, with larger magnitudes over land than over the oceans. On the contrary, annual surface temperature rises notably over Central Asia and most parts of Africa, as well as over northeasternmost Eurasia in the experiments TP60 to TP100. Meanwhile, the plateau uplift also leads to annual precipitation augmentation over the Tibetan Plateau but a reduction in northern Asia, the Indian Peninsula, much of Central Asia, parts of western Asia and the southern portions of northeastern Europe. Additionally, it is found that an East Asian summer monsoon system similar to that of the present initially exists in the TP60 and is gradually intensified with the continued plateau uplift. At 850 hPa the plateau uplift induces an anomalous cyclonic circulation around the Tibetan Plateau in summertime and two anomalous westerly currents respectively located to the south and north of the Tibetan Plateau in wintertime. In the mid-troposphere, similar-to-modern spatial pattern of summertime western North Pacific subtropical high is only exhibited in the experiments TP60 to TP100, and the East Asian trough is steadily deepened in response to the progressive uplift and expansion of the Tibetan Plateau. | 姜大膀 丁仲礼 Helge DRANGE 郜永祺 | 2008 | Advances in Atmospheric Sciences2008,25,5: | 13 |
| 13 | Global Wheat Head Detection(GWHD)Dataset:A Large and Diverse Dataset of High-Resolution RGB-Labelled Images to Develop and Benchmark Wheat Head Detection Methods显示文摘The detection of wheat heads in plant images is an important task for estimating pertinent wheat traits including head population density and head characteristics such as health,size,maturity stage,and the presence of awns.Several studies have developed methods for wheat head detection from high-resolution RGB imagery based on machine learning algorithms.However,these methods have generally been calibrated and validated on limited datasets.High variability in observational conditions,genotypic differences,development stages,and head orientation makes wheat head detection a challenge for computer vision.Further,possible blurring due to motion or wind and overlap between heads for dense populations make this task even more complex.Through a joint international collaborative effort,we have built a large,diverse,and well-labelled dataset of wheat images,called the Global Wheat Head Detection(GWHD)dataset.It contains 4700 high-resolution RGB images and 190000 labelled wheat heads collected from several countries around the world at different growth stages with a wide range of genotypes.Guidelines for image acquisition,associating minimum metadata to respect FAIR principles,and consistent head labelling methods are proposed when developing new head detection datasets.The GWHD dataset is publicly available at http://gffzzef49fa24bca249bbh6w0v0vb9fkww6bbb.ffgz.tsg.suse.edu.cn/and aimed at developing and benchmarking methods for wheat head detection. | Etienne David Simon Madec Pouria Sadeghi-Tehran Helge Aasen Bangyou Zheng Shouyang Liu Norbert Kirchgessner Goro Ishikawa Koichi Nagasawa Minhajul A.Badhon Curtis Pozniak Benoit de Solan Andreas Hund Scott C.Chapman Frédéric Baret Ian Stavness Wei Guo | 2020 | Plant Phenomics2020,2,1: | 13 |
| 14 | Regulation of the water status in three co-occurring phreatophytes at the southern fringe of the Taklamakan Desert显示文摘Aims We investigated the regulation of the water status in three predominant perennial C3 phreatophytes(Alhagi sparsifolia,Populus euphratica,Tamarix ramosissima)at typical sites of their occurrence at the southern fringe of the hyperarid Taklamakan Desert(north-west China).Methods In the foreland of the river oasis of Qira(Cele),we determined meteorological variables,plant biomass production,plant water potentials(WL)and the water flux through the plants.We calculated the hydraulic conductance on the flow path from the soil to the leaves(kSL)and tested the effects of kSL,WL and the leaf-to-air difference in the partial pressure of water vapour(Dw)on stomatal regulation using regression analyses.Important Findings Despite high values of plant water potential at the point of turgor loss,all plants sustained WL at levels that were high enough to maintain transpiration throughout the growing season.In A.sparsifolia,stomatal resistance(rs;related to leaf area or leaf mass)was most closely correlated with kSL;whereas in P.euphratica,~70%of the variation in rs was explained by Dw.In T.ramosissima,leaf area-related rs was significantly correlated with WL and kSL.The regulation mechanisms are in accordance with the growth patterns and the occurrence of the species in relation to their distance to the ground water. | Frank M.Thomas Andrea Foetzki Dirk Gries Helge Bruelheide Xiangyi Li Fanjiang Zeng Ximing Zhang | 2008 | Journal of Plant Ecology2008,1,4: | 13 |
| 15 | Gastric accommodation assessed by ultrasonography显示文摘胃的住所为在机能性消化不良的病理生理学的理解是重要的并且为在另外的混乱的症状产生也是相关的。术语胃的住所有至少三个不同意思:住所过程,调节反射,和住所反应。胃的住所过程是描述胃的分隔空间的尺寸怎么响应饭变化的复杂现象。电子 barostat 在估计胃的住所被认为标准答案。成像方法,包括的 MRI, SPECT,和 ultrasonography 可以也被使用,特别地在压力应答的病人,例如机能性消化不良病人,因为一个非侵略、不太导致压力的方法是赞成的。Ultrasonography 满足它不由自己弄歪的这些标准在压力应答的个人的生理的反应。 | Odd Helge Gilja Johan Lunding Trygve Hausken Hans Gregersen | 2006 | World Journal of Gastroenterology2006,12,18: | 12 |
| 16 | Ultrasonography in diagnosing chronic pancreatitis: New aspects显示文摘The course and outcome is poor for most patients with pancreatic diseases.Advances in pancreatic imaging are important in the detection of pancreatic diseases at early stages.Ultrasonography as a diagnostic tool has made,virtually speaking a technical revolution in medical imaging in the new millennium.It has not only become the preferred method for first line imaging,but also,increasingly to clarify the interpretation of other imaging modalities to obtain efficient clinical decision.We review ultrasonography modalities,focusing on advanced pancreatic imaging and its potential to substantially improve diagnosis of pancreatic diseases at earlier stages.In the first section,we describe scanning techniques and examination protocols.Their consequences for image quality and the ability to obtain complete and detailed visualization of the pancreas are discussed.In the second section we outline ultrasonographic characteristics of pancreatic diseases with emphasis on chronic pancreatitis.Finally,new developments in ultrasonography of the pancreas such as contrast enhanced ultrasound and elastography are enlightened. | Georg Dimcevski Friedemann G Erchinger Roald Havre Odd Helge Gilja | 2013 | World Journal of Gastroenterology2013,19,42: | 12 |
| 17 | Opposing intraspecific vs.interspecific diversity effects on herbivory and growth in subtropical experimental tree assemblages显示文摘Aims Positive plant diversity-ecosystem function relations are ultimately driven by variation in functional traits among individuals that form a community.To date,research has largely focused on the role of species diversity for ecosystem functioning.However,substantial intraspecific trait variation is common and a significant part of this variation caused by genetic differences among individuals.Here,we studied the relative importance of species diversity and seed family(SF)diversity within species for growth and herbivory in experimental subtropical tree assemblages.Methods In 2010,we set up a field experiment in subtropical China,using four species from the local species pool.Trees were raised from seeds,with seeds from the same mother tree forming an SF.We established 23 plots containing one or four species(species diversity treatment)and one or four SFs per species(SF diversity treatment).Tree growth(stem diameter,plant height and crown expansion)and herbivory(percentage leaf loss due to leaf chewers)were monitored annually from 2011 to 2013.Important findings Tree species richness promoted growth but had no effect on herbivory.In contrast,SF diversity reduced growth and increased herbivory but only so in species mixtures.Most of the observed effects were time dependent,with the largest effect found in 2013.Our results suggest that biodiversity can affect plant performance directly via tree species-species interactions,or context dependent,via potential effects on inter-trophic interactions.Two important conclusions should be drawn from our findings.Firstly,in future studies regarding biodiversity and ecosystem functioning(BEF)relationships,intraspecific genetic diversity should be given similar weight as species diversity as it has often been neglected and its effects are not well understood.Secondly,we demonstrate opposite effects of biodiversity among and within species,stressing the importance to consider the effects of multiple levels of biodiversity simultaneously. | Christoph Z.Hahn Pascal A.Niklaus Helge Bruelheide Stefan G.Michalski Miaomiao Shi Xuefei Yang Xueqin Zeng Markus Fischer Walter Durka | 2017 | Journal of Plant Ecology2017,10,1: | 11 |
| 18 | Is irritable bowel syndrome an organic disorder?显示文摘Irritable bowel syndrome(IBS)is a common gastrointestinal disorder that is generally considered to be functional because there appears to be no associated anatomical defect.Stress and psychological factors are thought to play an important role in IBS.The gut neuroendocrine system(NES),which regulates all functions of the gastrointestinal tract,consists of endocrine cells that are scattered among the epithelial cells of the mucosa,and the enteric nervous system.Although it is capable of operating independently from the centra nervous system(CNS),the gut NES is connected to and modulated by the CNS.This review presents evidence for the presence of an anatomical defect in IBS patients,namely in the gastrointestinal endocrine cells.These cells have specialized microvilli that project into the lumen and function as sensors for the luminal content and respond to luminal stimuli by releasing hormones into the lamina propria,which starts a chain reaction that progresses throughout the entire NES.The changes in the gastrointestinal endocrine cells observed in IBS patients are highly consistent with the other abnormalities reported in IBS patients,such as visceral hypersensitivity,dysmotility,and abnormal secretion. | Magdy El-Salhy Doris Gundersen Odd Helge Gilja Jan Gunnar Hatlebakk Trygve Hausken | 2014 | World Journal of Gastroenterology2014,20,2: | 11 |
| 19 | Endocrine cells in the oxyntic mucosa of the stomach in patients with irritable bowel syndrome显示文摘AIM: To study the different endocrine cell types in the oxyntic mucosa of patients with irritable bowel syndrome(IBS).METHODS: Seventy-six patients with IBS were included in the study(62 females and 14 males; mean age 32 years, range 18-55 years), of which 40 also fulfilled the Rome Ⅲ criteria for functional dyspepsia(FDP). Of the entire IBS cohort, 26 had diarrhea as the predominant symptom(IBS-D), 21 had a mixture of diarrhea and constipation(IBS-M), and 29 had constipation as the predominant symptom(IBS-C). Fortythree age and sex-matched healthy volunteers withoutany gastrointestinal complaints served as controls. The patients were asked to complete the Birmingham IBS symptom questionnaire. Both the patients and controls underwent a standard gastroscopy, during which three biopsy samples were taken from the corpus. Sections from these biopsy samples were immunostained using the avidin-biotin complex(ABC) method, for ghrelin, serotonin, somatostatin and histamine. The densities of these cell types and immunoreactivity intensities were quantified using computerized image analysis with Olympus cellSens imaging software(version 1.7).RESULTS: The densities of the ghrelin cells in the control, IBS-total, IBS-D, IBS-M and IBS-C groups were 389(320, 771), 359(130, 966), 966(529, 1154), 358(120, 966) and 126(0, 262) cells/mm2, respectively. There was a significant difference between the tested groups(P < 0.0001). Dunn's multiple comparison test showed that the ghrelin cell density was significantly higher in IBS-D and lower in IBS-C than in the controls(P = 0.03 and 0.0008, respectively). The ghrelin cell density in patients with both IBS and FDP was 489(130, 966), and in those with IBS only 490(130, 956). There was no statistical significant difference between these 2 groups of patients(P = 0.9). The immunoreactivity intensity did not differ between any of the groups(P = 0.6). The diarrhea score of the Birmingham IBS symptom questionnaire was significantly positively correlated with ghrelin cell density(r = 0.65; P < 0.0001) and significantly inversely correlated with that of constipation(r = 90.69; P < 0.0001). The densities of the serotonin cells were 63(51, 82), 51(25, 115), 120(69, 128), 74(46, 123) and 40(0, 46) cells/mm2 in the control, IBS-total, IBS-D, IBS-M and IBS-C groups, respectively. A statistically significant difference was found between the tested groups(P < 0.0001). Posttest revealed that serotonin cell density was significantly higher in IBS-D and lower in IBS-C than in controls(P = 0.02 and 0.004, respectively), but did not differ in the IBS-total and IBS-M groups from that in controls(P = 0.5 and 0.4, respectively). The serotonin cell densityin patients with both IBS and FDP was 62(25, 115)and in those with IBS only 65(25, 123). There was no statistically significant difference between these2 groups of patients(P = 1). The immunoreactivity intensity of serotonin did not differ significantly between any of the groups(P = 0.0.9). The serotonin cell density was significantly positively correlated with the diarrhea score of the Birmingham IBS symptom questionnaire(r = 0.56; P < 0.0001) and significantly inversely correlated with that of constipation(r = 0.51;P < 0.0001). The densities of the somatostatin cells were 97(72, 126), 72(0, 206), 29(0, 80), 46(0, 103)and 206(194, 314) cells/mm2 in the control, IBS-total,IBS-D, IBS-M and IBS-C groups, respectively(Figures7 and 8). There was a statistically significant difference between the controls and the IBS subgroups(P <0.0001). The density of somatostatin cells was significantly lower in the IBS-D and IBS-M groups but higher in IBS-C patients than in the controls(P < 0.01, P =0.02, and P = 0.0008, respectively). The somatostatin cell density in patients with both IBS and FDP was 86(0-194), and in those with IBS only 110(0-206). There was no statistically significant difference between these 2 groups of patients(P = 0.6). There was no significant difference in somatostatin immunoreactivity intensity between the controls. The diarrhea score of the Birmingham IBS symptom questionnaire was inversely correlated with somatostatin cell density(r =0.38; P = 0.0007) and was positively correlated with that of constipation(r = 0.64; P < 0.0001).CONCLUSION: The finding of abnormal endocrine cells in the oxyntic mucosa shows that the endocrine cell disturbances in IBS are not restricted to the intestine. Furthermore, it appears that ghrelin, serotonin and somatostatin in the oxyntic mucosa of the stomach may play an important role in the changing stool habits in IBS through their effects on intestinal motility. | Magdy El-Salhy Odd Helge Gilja Doris Gundersen Trygve Hausken | 2014 | World Journal of Gastrointestinal Endoscopy2014,6,5: | 11 |
| 20 | 耦合模式长期积分中东亚夏季风与ENSO联系的不稳定性显示文摘通过对挪威卑尔根全球大气 -海洋 -海冰耦合模式 30 0a控制积分结果进行交叉子波分析 ,揭示了东亚夏季风 (EASM )与同期Ni no3区 (90 °W~ 15 0 °W ,5 °S~ 5 °N)海洋表面温度异常的相关关系在长期变化中是不稳定的 ,呈现出明显的阶段性特征 .气候要素场在二者联系的紧密 (HCP)和微弱 (LCP)时期差别显著 ,在HCP时期 ,西北太平洋对流层低层出现一对耦合的异常气旋和反气旋性环流系统 ;东南亚地区对流层低层表现为强东风异常 ,风速的年际变率加大 ;热带西太平洋对流层温度和位势高度场的年际变率普遍加强 .此外 ,中国夏季降水与同期Ni | 姜大膀 王会军 Drange Helge 郎咸梅 | 2004 | 地球物理学报2004,47,6: | 10 |