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Association analysis of an anti-obesity mechanism and key ripened Pu-erh tea bioactive components by mimicking human general tea drinking
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作者 Junyu Liu Zhengyang Song +12 位作者 Haihong Chen Wen Zeng Guirong Han Wei Li Bing Xu Yuan Lu Canyang Zhang Zhenglian Xue Bin Lü Chong Zhang Song Yang Yi Wang Xinhui Xing 《Food Science and Human Wellness》 2025年第2期450-468,共19页
Pu-erh tea,a traditional Chinese beverage,performs an anti-obesity function,but the correlation between its components and efficacy remains unknown.Here,we screened two Pu-erh teas with significant anti-obesity effica... Pu-erh tea,a traditional Chinese beverage,performs an anti-obesity function,but the correlation between its components and efficacy remains unknown.Here,we screened two Pu-erh teas with significant anti-obesity efficacies from 11 teas.In vitro experiments revealed that lipid accumulation in L02 cells and lipid synthesis in 3T3-L1 cells were significantly better inhibited by Tea-B than Tea-A.Further in vivo experiments using model mice revealed that the differences in chemical components generated two pathways in the anti-obesity efficacy and mechanism of Pu-erh teas.Tea-A changes the histomorphology of brown adipose tissue(BAT)and increases the abundance of Coriobacteriaceae_UCG_002 and cyclic AMP in guts through high chemical contents of cyclopentasiloxane,decamethyl,tridecane and 1,2,3-trimethoxybenzene,eventually increasing BAT activation and fat browning gene expression;the high content of hexadecane and 1,2-dimethoxybenzene in Tea-B reduces white adipose tissue(WAT)accumulation and the process of fatty liver,increases the abundance of Odoribacter and sphinganine 1-phosphate,inhibits the expression of lipid synthesis and transport genes.These mechanistic findings on the association of the representative bioactive components in Pu-erh teas with the anti-obesity phenotypes,gut microbes,gut metabolite structure and anti-obesity pathways,which were obtained for the first time,provide foundations for developing functional Pu-erh tea. 展开更多
关键词 ANTI-OBESITY Bioactive components Lipid metabolism Multiomics analysis Pu-erh tea
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Land-use legacies affect the composition and distribution of tree species and their belowground functions in a succession from old-field to mature temperate forest
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作者 Gisselle A.Mejía Chenyang Su +2 位作者 David Allen VBala Chaudhary Theresa W.Ong 《Forest Ecosystems》 CSCD 2024年第6期960-973,共14页
Forests undergoing ecological succession following abandonment from agricultural use(i.e.,old fields)are ubiquitous in temperate regions of the U.S.and Europe.Ecological succession in old fields involves changes in ve... Forests undergoing ecological succession following abandonment from agricultural use(i.e.,old fields)are ubiquitous in temperate regions of the U.S.and Europe.Ecological succession in old fields involves changes in vegetation composition influenced by factors such as land-use history,soil conditions,and dispersal limitations.Species’behavioral,morphological,physiological and life-history attributes influence the outcomes of environmental and biotic filters on distribution and abundance.However,many studies have focused on aboveground attributes,while less attention has been placed on belowground species characteristics that influence community assembly and function.In this study,we used a trait-based approach to examine how aboveground plant composition and distribution vary with plant root functional traits(e.g.,mycorrhizal association)that mediate access for nutrients such as nitrogen(N)and phosphorous(P).We inventoried every tree stem(n=11,551)in a 10-ha forested area containing old-field and historical forests and matched every species with root functional traits(n=33)from established databases.We found that land-use history influences community composition and distribution in old-field forests,which also varied with belowground root functional traits.Community composition in old-field forests,which were dominated by Acer saccharum and non-native species,were largely associated with arbuscular mycorrhizae(AM)and higher root nutrient concentrations.On the other hand,community composition in historical forests–largely dominated by Tsuga canadensis–were associated with ectomycorrhiza(EcM)and more variation of root length and depth.These results suggest that changes in aboveground communities have implications for belowground ecosystem services(e.g.,nutrient cycling)which are important to forest ecosystem development.Trait-based approaches can elucidate mechanisms of community assembly,and understanding how traits influence species coexistence and interactions can inform management decisions related to biodiversity conservation and restoration efforts in disturbed or altered forests. 展开更多
关键词 Fine roots Belowground processes Old fields SUCCESSION Trait-based ecology Community assembly
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委内瑞拉链霉菌中氯霉素生物合成基因的克隆 被引量:1
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作者 何建勇 姚新生 Leo.C.Vining 《沈阳药科大学学报》 CAS CSCD 北大核心 2006年第11期731-734,共4页
目的克隆委内瑞拉链霉菌(Streptomyces venezuelae)ISP5230中的氯霉素生物合成基因。方法以pabAB基因片段为探针,通过菌落杂交技术从该菌的基因文库中钓取相关基因。结果得到一7.5kbBamHIBamHI DNA片段,突变株的互补实验表明,该7.5kb DN... 目的克隆委内瑞拉链霉菌(Streptomyces venezuelae)ISP5230中的氯霉素生物合成基因。方法以pabAB基因片段为探针,通过菌落杂交技术从该菌的基因文库中钓取相关基因。结果得到一7.5kbBamHIBamHI DNA片段,突变株的互补实验表明,该7.5kb DNA片段使氯霉素生物合成阻断变株CML-4恢复了氯霉素的生物合成。从野生菌株的染色体上删除该7.5 kb DNA片段中的一段3.5 kbNcoINcoI DNA片段后,野生菌株丧失了氯霉素的生物合成能力。结论该7.5 kb DNA片段含有氯霉素生物合成所需的基因。 展开更多
关键词 基因克隆 委内瑞拉链霉菌 氯霉素
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棘阿米巴角膜炎的感染免疫及防治 被引量:5
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作者 李志杰 C.Wayne Smith 《眼科新进展》 CAS 2005年第2期101-104,共4页
棘阿米巴角膜炎是棘阿米巴属引起的角膜表面的感染。通常由粘附于软性接触镜的棘阿米巴滋养体所传递。当寄生虫粘附于角膜上皮细胞表面时可触发感染。后来的过程包括:寄生虫介导的细胞病理效应、诱导凋亡和通过产生各种蛋白酶入侵角膜... 棘阿米巴角膜炎是棘阿米巴属引起的角膜表面的感染。通常由粘附于软性接触镜的棘阿米巴滋养体所传递。当寄生虫粘附于角膜上皮细胞表面时可触发感染。后来的过程包括:寄生虫介导的细胞病理效应、诱导凋亡和通过产生各种蛋白酶入侵角膜基质层。滋养体也可浸润角膜神经,造成放射状角膜神经炎。棘阿米巴包囊即具有免疫原性又具有抗原性。然而,诱导针对棘阿米巴抗原的细胞介导的免疫应答对棘阿米巴角膜炎即无减轻作用又无预防效应。但是,普通粘膜免疫系统对于棘阿米巴角膜炎却具有显著的预防作用。其机制是通过IgA抗体阻断感染性滋养体与上皮层的结合。局部使用糖皮质激素对于缓解疼痛和减轻炎症反应具有显著效果,但可通过诱导静止包囊的脱包囊、增加滋养体的细胞病理效应以及麻痹初始免疫系统使疾病复燃。因此,糖皮质激素的使用是一把“双刃剑”。 展开更多
关键词 棘阿米巴 角膜炎 感染 免疫
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交感性眼炎的免疫病理学及其免疫治疗 被引量:4
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作者 李志杰 C.Wayne Smith 《眼科新进展》 CAS 2005年第1期1-4,共4页
交感性眼炎是一眼穿透性外伤后发生的双侧肉芽肿性葡萄膜炎。其主要病理特征为葡萄膜的弥散性非坏死性肉芽肿性炎症反应。免疫病理学研究证实 :T淋巴细胞在发病机制中起着重要的作用。疾病早期的T淋巴细胞主要为CD4 + 细胞 ,而晚期则以C... 交感性眼炎是一眼穿透性外伤后发生的双侧肉芽肿性葡萄膜炎。其主要病理特征为葡萄膜的弥散性非坏死性肉芽肿性炎症反应。免疫病理学研究证实 :T淋巴细胞在发病机制中起着重要的作用。疾病早期的T淋巴细胞主要为CD4 + 细胞 ,而晚期则以CD8+ 细胞为主。B细胞占脉络膜浸润细胞的 2 0 %以下 ,可能与疾病的慢性过程相关。另外 ,局部还存在黏附分子、MHC和FasL等免疫相关分子的表达增加。交感性眼炎患者具有一定的遗传倾向 ,与宿主的HLA状态存在某种关联性。其治疗原则是使用免疫抑制剂尽快控制眼内炎症 ,但应密切观察其相应的毒副作用。另外 ,还讨论了有关眼球摘除的问题。 展开更多
关键词 交感性眼炎 免疫机制 免疫疗法
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浅析协同效应的理论模型与应用拓展 被引量:12
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作者 梁妍钰 王志鹏 《大学化学》 CAS 2017年第2期89-97,共9页
从基础物理化学分析入手,结合生物化学、生物无机化学、酶学和超分子化学等多学科实例,对协同效应的原理和应用进行系统性的全面阐述。以期对教学与相关科研有帮助。
关键词 协同效应 “S”型曲线 希尔方程 血红蛋白 生物素
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Vascular Transcriptome Profiling Reveals Aging-Related Genes in Angiotensin Ji-Induced Hypertensive Mouse Aortas 被引量:5
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作者 Shuangjie Lv Yangnan Ding +5 位作者 Xiaoya Pei Xiang Zhao Delong Hao Zhuqin Zhang Houzao Chen Depei Liu 《Chinese Medical Sciences Journal》 CAS CSCD 2020年第1期43-53,共11页
Objective AngiotensinⅡ(AngⅡ)-induced vascular damage is a major risk of hypertension.However,the underlying molecular mechanism of AngⅡ-induced vascular damage is still unclear.In this study,we explored the novel m... Objective AngiotensinⅡ(AngⅡ)-induced vascular damage is a major risk of hypertension.However,the underlying molecular mechanism of AngⅡ-induced vascular damage is still unclear.In this study,we explored the novel mechanism associated with Ang Il-induced hypertension.Methods We treated 8-to 12-week-old C57BL/6J male mice with saline and AngⅡ(0.72 mg/kg-d)for 28 days,respectively.Then the RNA of the media from the collected mice aortas was extracted for transcriptome sequencing.Principal component analysis was applied to show a clear separation of different samples and the distribution of differentially expressed genes was manifested by Volcano plot.Functional annotations including Gene Ontology(GO)and Koto Encyclopedia of Genes and Genomes(KEGG)pathway were performed to reveal the molecular mechanism of AngⅡ-induced hypertension.Finally,the differentially expressed genes were validated by using quantitative real-time PCR.Results The result revealed that a total of 773 genes,including 599 up-regulated genes and 174 down-regulated genes,were differentially expressed in the aorta of AngⅡ-induced hypertension mice model.Functional analysis of differentially expressed genes manifested that various cellular processes may be involved in the AngⅡ-induced hypertension,including some pathways associated with hypertension such as extracellular matrix,inflammation and immune response.Interestingly,we also found that the differentially expressed genes were enriched in vascular aging pathway,and further validated that the expression levels of insulin-like growth factor 1 and adiponectin were significantly increased(P<0.05).Conclusion We identify that vascular aging is involved in AngⅡ-induced hypertension,and insulin-like growth factor 1 and adiponectin may be important candidate genes leading to vascular aging. 展开更多
关键词 hypertension VASCULAR aging ANGIOTENSIN II TRANSCRIPTOME SEQUENCING
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Conspecific negative density dependence in American beech 被引量:1
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作者 Benjamin S.Ramage Isabel J.Mangana 《Forest Ecosystems》 SCIE CSCD 2017年第3期174-181,共8页
Background: One of the most important drivers of forest biodiversity is conspecific negative density dependence(CNDD), a reduction in performance when conspecific densities are high. While the majority of CNDD rese... Background: One of the most important drivers of forest biodiversity is conspecific negative density dependence(CNDD), a reduction in performance when conspecific densities are high. While the majority of CNDD research has focused on tropical forests, evidence is mounting that CNDD may also play an important role in temperate forests.To further explore the potential reach of this phenomenon, we investigated CNDD in American beech(Fagus grandifolia)in a mature mid-Atlantic forest.Methods: We used bivariate point pattern analyses to examine spatial relationships between large beech trees and conspecific saplings, and we also contrasted these patterns with comparable patterns for heterospecifics. In addition, to address the possibility of dispersal limitation and the associated effects on spatial patterns, we analyzed seedling density as a function of adult conspecific abundance.Results: We found that beech saplings were more repel ed from large conspecifics than large heterospecifics, despite the fact that beech seedling density was positively correlated with beech basal area. However, saplings of other canopy tree species were also repel ed from adult beech trees, suggesting a general suppressive effect. Nonetheless, the discrepancy between beech seedling and sapling densities beneath adult conspecifics suggests that beech seedling survival rates were reduced in vicinity of conspecific adults.Conclusions: Regardless of the extent to which beech inhibits heterospecific trees, a negative effect on conspecific recruits may be critical for biodiversity maintenance. Without this conspecific suppression, a dense layer of shade-tolerant beech saplings could form beneath adult beech trees. If this were to occur, beech would have a substantial head-start fol owing canopy disturbance, and this late-successional species could potential y dominate a stand in perpetuity,through repeated disturbance cycles. 展开更多
关键词 BIODIVERSITY DISTURBANCE Dispersal limitation Diversity Fagus grondifolia Janzen-Connell effects MID-ATLANTIC Point pattern analysis REGENERATION Temperate forest
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Chicory polysaccharides alleviate high-fat diet-induced non-alcoholic fatty liver disease via alteration of lipid metabolism-and inflammation-related gene expression 被引量:4
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作者 Shengjie Li Yulong Wu +4 位作者 Haitao Jiang Feng Zhou Ailing Ben Renlei Wang Chun Hua 《Food Science and Human Wellness》 SCIE 2022年第4期954-964,共11页
Administration of chicory polysaccharides(CP) can modify lipid metabolism, improve dyslipidemia, and reduce liver inflammation, all of which may help alleviate non-alcoholic fatty liver disease(NAFLD). However, the un... Administration of chicory polysaccharides(CP) can modify lipid metabolism, improve dyslipidemia, and reduce liver inflammation, all of which may help alleviate non-alcoholic fatty liver disease(NAFLD). However, the underlying mechanisms remain unclear. This study aimed to gain further understanding of the potential molecular mechanisms that mediate the protective effects of CP against NAFLD via transcriptomic and metabolomic analyses. Hepatic RNA-sequencing analysis demonstrated that long-term intake of CP restored expression of lipid metabolism-related genes Xbp1, Insig2, and Cth in NAFLD rats, thereby inhibiting de novo lipogenesis. Moreover, CP consumption restored expression levels of genes involved in pro-inflammatory responses, such as Irf1. In addition, metabolic data confirmed that CP treatment increased levels of L-palmitoylcarnitine and hexadecanoyl-Co A, implying that CP administration can promote hepatic fatty acid β-oxidation. The present results demonstrate the underlying mechanisms of CP in high-fat dietinduced NAFLD rats and suggest that CP treatment might provide a dietary therapeutic tool for the treatment of NAFLD in humans. 展开更多
关键词 Chicory polysaccharides Non-alcoholic fatty liver disease TRANSCRIPTOME METABOLOME
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A fine-scale assessment of the ecosystem service-disservice dichotomy in the context of urban ecosystems affected by alien plant invasions 被引量:1
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作者 Luke J.Potgieter Mirijam Gaertner +1 位作者 Patrick J.O’Farrell David M.Richardson 《Forest Ecosystems》 SCIE CSCD 2019年第4期323-338,共16页
Background: Natural resources within and around urban landscapes are under increasing pressure from ongoing urbanisation, and management efforts aimed at ensuring the sustainable provision of ecosystem services(ES) ar... Background: Natural resources within and around urban landscapes are under increasing pressure from ongoing urbanisation, and management efforts aimed at ensuring the sustainable provision of ecosystem services(ES) are an important response. Given the limited resources available for assessing urban ES in many cities, practical approaches for integrating ES in decision-making process are needed.Methods: We apply remote sensing techniques(integrating LiDAR data with high-resolution multispectral imagery)and combined these with supplementary spatial data to develop a replicable approach for assessing the role of urban vegetation(including invasive alien plants) in providing ES and ecosystem disservices(EDS). We identify areas denoting potential management trade-offs based on the spatial distribution of ES and EDS using a local-scale case study in the city of Cape Town, South Africa. Situated within a global biodiversity hotspot, Cape Town must contend with widespread invasions of alien plants(especially trees and shrubs) along with complex socio-political challenges. This represents a useful system to examine the challenges in managing ES and EDS in the context of urban plant invasions.Results: Areas of high ES provision(for example carbon sequestration, shade and visual amenity) are characterized by the presence of large trees. However, many of these areas also result in numerous EDS due to invasions of alien trees and shrubs – particularly along rivers, in wetlands and along the urban edge where tall alien trees have established and spread into the natural vegetation(for example increased water consumption, increased fire risk and reduced soil quality). This suggests significant trade-offs regarding the management of species and the ES and EDS they provide.Conclusions: The approach applied here can be used to provide recommendations and to guide city planners and managers to fine-tune management interventions at local scales to maximise the provision of ES. 展开更多
关键词 BIODIVERSITY Biological invasions Ecosystem disservices Ecosystem services Remote sensing Trade-offs Tree invasions Urban plant invasions
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A QUASILINEAR SINGULAR ELLIPTIC SYSTEM WITHOUT COOPERATIVE STRUCTURE 被引量:1
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作者 Dumitru MOTREANU Abdelkrim MOUSSAOUI 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期905-916,共12页
In this article, we investigate the existence of positive solutions of a singular quasilinear elliptic system for which the cooperative structure is not required. The approach is based on the Schauder fixed point theo... In this article, we investigate the existence of positive solutions of a singular quasilinear elliptic system for which the cooperative structure is not required. The approach is based on the Schauder fixed point theorem combined with perturbation arguments that involve the singular terms. 展开更多
关键词 Singular system p-Laplacian Schauder's fixed point theorem bounded solution Moser iteration
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Functional trait and community phylogenetic analyses reveal environmental filtering as the major determinant of assembly of tropical forest tree communities in the Western Ghats biodiversity hotspot in India 被引量:2
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作者 K.Nagaraju Shivaprakash B.R.Ramesh +1 位作者 Ramanan Umashaanker Selvadurai Dayanandan 《Forest Ecosystems》 SCIE CSCD 2018年第4期345-360,共16页
Background: Improved understanding of the processes shaping the assembly of tropical tree communities is crucial for gaining insights into the evolution of forest communities and biological diversity. The climate is t... Background: Improved understanding of the processes shaping the assembly of tropical tree communities is crucial for gaining insights into the evolution of forest communities and biological diversity. The climate is thought to be the first order determinant of abundance and distribution patterns of tree species with contrasting traits such as evergreen and deciduous leaf phenology. However, the relative role of neutral, and niche-based processes in the evolution of these patterns remain poorly understood.Methods: Here, we perform an integrated analysis of the data on tree species abundance, functional traits and community phylogeny from a network of 96 forest plots, each 1 ha in size, distributed along a broad environmental gradient in the central Western Ghats, India. Then, we determine the relative importance of various process in assembly and structuring of tropical forest communities with evergreen and deciduous leaf phenology.Results: The deciduous leaf phenological trait has repeatedly evolved among multiple distantly related lineages. Tree communities in dry deciduous forests were phylogenetically clustered and showed a low range and variance of functional traits related to light harvesting, reproduction, and growth suggesting niche-based processes such as environmental filtering play a vital role in the assembly of tree communities in these forests. The external factors such as human-mediated disturbance also significantly, but to a lesser extent, influences the species and phylogenetic turnover.Conclusions: These findings revealed that the environmental filtering plays a significant role in assembly of tree communities in the biologically diverse tropical forests in the Western Ghats biodiversity hotspot. 展开更多
关键词 Functional traits Phylogenetic turnover DECIDUOUS EVERGREEN Niche-based processes Human disturbance
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RNA-binding Protein UNR Promotes Glioma Cell Migration and Regulates the Expression of Ribosomal Protein L9 被引量:1
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作者 Ningyu Tian Yingjiao Qi +5 位作者 Yan Hu Bin Yin Jiangang Yuan Boqin Qiang Xiaozhong Peng Wei Han 《Chinese Medical Sciences Journal》 CAS CSCD 2018年第3期143-151,共9页
Objective To investigate the role of RNA binding protein—upstream-of-N-Ras(UNR) in the development of glioma and its molecular mechanism.Methods First, bioinformatics analysis of CGGA database was performed to detect... Objective To investigate the role of RNA binding protein—upstream-of-N-Ras(UNR) in the development of glioma and its molecular mechanism.Methods First, bioinformatics analysis of CGGA database was performed to detect UNR expression level and prognosis of patients with glioma. Western blot and real-time PCR were used to detect UNR expression level in glioma cell lines and tissues. Next, UNR siRNAs were transfected in glioma cells, and MTS assay and scratch wound-healing assay were used to detect changes in cell proliferation and migration. Then, the candidate UNR target mRNAs were identified by analyzing the sequencing data of UNR iCLIP-seq, RNA sequencing and ribosome profiling databases of human melanoma. RNA immunoprecipitation and biotin pull-down assays were used to identify the UNR target mRNAs in glioma cells. Finally, western blot was used to detect the effect of UNR knockdown on ribosomal protein L9(RPL9) and RPL9 protein expression level in glioma cell lines. RPL9 siR NA was transfected in A172 and T98 G and the expression of vimentin in the cells was detected with western blot.Results Bioinformatics analysis showed that UNR mRNA expression level was significantly higher in highgrade glioma [Grade Ⅱ(n=126), Grade Ⅲ(n=51), Grade Ⅳ(n=128), P<0.001]. UNR high expression levels were associated with poor prognosis(P=0.0177). UNR had high expression level in glioma cell lines and patient samples compared with normal cell lines and normal brain samples(P<0.01). Knockdown of UNR inhibited glioma cells migration(P<0.05), but did not inhibit glioma cells growth in three glioma cell lines. UNR binded the 3' untranslated region(UTR) of PTEN and RPL9 mRNAs. RPL9 protein was significantly highly expressed in most glioma cell lines(n=9) and knockdown of UNR resulted in a downregulation of RPL9 protein expression.Epithelial-mesenchymal transition(EMT)-related marker—vimentin was positively regulated by RPL9.Conclusions UNR could bind to the 3'UTR of PTEN and RPL9 in glioma cell lines, therefore promoting glioma cell migration and regulating the expression of RPL9. Here, we establish a link between UNR and RPL9 protein, which will provide new ideas for the further study of glioma. 展开更多
关键词 UNR GLIOMA MIGRATION RIBOSOMAL PROTEIN L9 VIMENTIN
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Use of non-timber forest products from invasive alien Prosopis species(mesquite) and native trees in South Africa: implications for management 被引量:1
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作者 Ross T Shackleton David C Le Maitre +1 位作者 Brian W van Wilgen David M Richardson 《Forest Ecosystems》 SCIE CSCD 2015年第3期197-207,共11页
Background: Prosopis species have been introduced to many areas outside their native range to provide benefits to local communities. Several Prosopis species and their hybrids(hereafter "mesquite") have, how... Background: Prosopis species have been introduced to many areas outside their native range to provide benefits to local communities. Several Prosopis species and their hybrids(hereafter "mesquite") have, however, become naturalised and invasive and now generate substantial costs. Management options are limited because of the complex conflicts of interest regarding benefits and costs. Management policies and strategies must take account of such conflicts, but further insights are needed on the dimensions of uses and impacts before such information can be usefully applied. Current policy in South Africa allows for the growth and use of mesquite in one province,but not in others where its control is mandatory. We report on a study to quantify the direct use and perceptions of non-timber forest products(NTFPs) from mesquite and native trees in South Africa.Methods: Semi-structures household interviews were conducted with various stakeholder groups to identify what tree products are used, to ascertain amounts used as well as to gauge perceptions of natural resource use between different tree species and use over time.Results: The direct household use value of native trees was higher than that of mesquite, and local stakeholders attached greater value to products from native trees than from mesquite. Therefore, native trees are and will still be preferentially harvested, and mesquite is unlikely to offer protection to native species by providing an alternative source of products. Mesquite pods do, however, provide valuable additional resources(fodder and medicinal products). The use of both native trees and mesquite is decreasing as the incomes of poorer households rise and as alternative energy sources become available. The benefits and reliance on mesquite are not as high as previously assumed and the impacts from mesquite invasions create large problems for local communities.Conclusion: This study provides further evidence that the impacts of mesquite exceed the benefits, lending support for a policy to reduce negative impacts. 展开更多
关键词 Biological invasions Conflicts of interests Cost v
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Ex vivo differentiation of multipotent adult progenitor cells to skin epidermal cells 被引量:1
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作者 Ji Kaihong Xiong Jun Fan Lixing Hu Kaimeng Liu Houqi 《Journal of Medical Colleges of PLA(China)》 CAS 2009年第2期84-91,共8页
Objective: By establishing the indirect contact co-culture system, we studied the in vitro condition for MAPCs differentiating into epidermal cells and the transformation of MAPCs into epidermal cell phenotype. Meth... Objective: By establishing the indirect contact co-culture system, we studied the in vitro condition for MAPCs differentiating into epidermal cells and the transformation of MAPCs into epidermal cell phenotype. Methods: Cell culture insert membrane was used for substitute basal membrane and MAPCs, fibroblast cells (FCs) and mixture of MAPCs and epidermal cells and FCs were separately implanted into 2 sides of it. PKH26 was used to label cloned MAPCs; type IV collagen rapid adhering method was used to isolate and culture the skin epidermal cells from l-day-old SD rat. Results: Part of the MAPCs transformed into cells expressing keratin in the presence of peripheral epithelia and FCs. Type Ⅳ collagen rapid adhering method successfully selected rats' epidermal stem cells. The mixture of the 2 kinds of cells or indirect culture might promote the differentiation through mesenchymal factors secreted by dermis FC. Conclusion: We were the first to have established the in vitro model of MAPCs differentiation into epidermal cells, in which MAPCs were transformed into epithelium-like cells. 展开更多
关键词 Cell differentiation In vitro model Epidermal cell
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Physical properties of soil in Pine elliottii and Eucalyptus cloeziana plantations in the Vhembe biosphere,Limpopo Province of South Africa 被引量:1
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作者 Vukeya Emment Ntshuxeko Sheunesu Ruwanza 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第2期625-635,共11页
Plantation establishment using invasive alien plants is common in South Africa,but the effects of these plants on soil physical properties in the Vhembe biosphere is unknown.In this comparative study,soils underneath ... Plantation establishment using invasive alien plants is common in South Africa,but the effects of these plants on soil physical properties in the Vhembe biosphere is unknown.In this comparative study,soils underneath Pinus elliottii and Eucalyptus cloeziana were assessed for differences in physical properties compared to soils underneath adjacent natural sites in the Entabeni plantation in the Vhembe biosphere in Limpopo Province,South Africa.Soils were collected from topsoil over 3 months and quantified for gravimetric soil moisture,penetration resistance,soil infiltration,hydraulic conductivity and soil water repellency.For all 3 months,soils from both P.elliottii and E.cloeziana plantations were compact and had low penetration resistance compared to soils from adjacent natural sites.Soil infiltration and hydraulic conductivity were significantly(p\0.05)lower in soils from plantations compared to soils from adjacent natural sites,and more so from the E.cloeziana plantation than from P.elliottii.Soil water repellency was observed in soils from E.cloeziana only in May and June.Soils from the invasive alien tree plantation have decreased soil moisture,infiltration rate,hydraulic conductivity and are compact as well as repellent(only E.cloeziana),all poor soil physical properties.However,this decline in soil physical properties was not uniform between the two invasive alien plantation species;hence we cannot generalize about the effects of invasive alien plantation species on soil physical properties,and further research is required across different ecological regions. 展开更多
关键词 LITTER Biomass HYDROPHOBICITY Invasive alien trees Soil water repellency
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竹材结构的防腐(英文) 被引量:4
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作者 Walter Liese 《世界竹藤通讯》 2005年第2期16-21,共6页
由于在露天环境中遭遇生物腐蚀,竹秆的持久性差,所以需要采取化学手段增强其耐力。但是它的解剖构造使化学物质难以像木材那样容易进入竹材。竹秆的外部由其表皮保护防水,不像木材那样有径向渗透的途径。而其内部腔隙也有保护性纤维。... 由于在露天环境中遭遇生物腐蚀,竹秆的持久性差,所以需要采取化学手段增强其耐力。但是它的解剖构造使化学物质难以像木材那样容易进入竹材。竹秆的外部由其表皮保护防水,不像木材那样有径向渗透的途径。而其内部腔隙也有保护性纤维。化学物质的主要渗透途径位于竹秆根部微管束的后生木质部。这些渗透途径分布于横剖面,很不均匀,且少,只占总面积的8~10%,而且在通过竹节时改变方向。由于在采伐时砍伤竹秆,通向导管的细胞腔被堵塞,渗透途径也受影响。周围的薄壁细胞是竹秆组织的主要部分,它们通过微小的纹孔互相连接,只能通过弥散进入。它们所含的淀粉是昆虫和某些真菌的食品。对纤维的保护也有赖于弥散。用化学物质进行保护,对于新鲜的含水量高的竹秆效果最好。就像简单的根部处理,或技术性较强的细胞液改善。新鲜竹秆的薄壁组织和纤维也能通过垂直弥散的方法得到保护。如进行滴渍和浸渍工作,最好在竹材含水分时劈开,因为薄壁组织容易接受弥散。技术措施如竹秆的水分储存和熏蒸的过程,与竹秆的自然结构,尤其是薄壁组织有关。 展开更多
关键词 竹子 秆结构 保护 处理能力 防腐措施 竹材结构 薄壁组织 防腐 化学物质 根部处理
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Katherine Mansfield: A Special Feminist-By a Close Reading of A Dill Pickle 被引量:3
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作者 何丹丽 《海外英语》 2011年第8X期295-296,303,共3页
Although Katherine Mansfield never claimed that she was a radical feminist, she showed her concerns and pondered on females through her life of pursuing freedom and independence, her creative writing skills and her sh... Although Katherine Mansfield never claimed that she was a radical feminist, she showed her concerns and pondered on females through her life of pursuing freedom and independence, her creative writing skills and her short stories. She had her own feminism consciousness and viewpoints. She believed that man and woman were different and living in a different world, and it's very hard to understand and communicate with the other sex. Man dominated the society in the economical and political areas in tradition that they had the speech right and ranked above woman. However, Mansfield saw the hope of the awakening of the feminism awareness. 展开更多
关键词 FEMINIST FEMINISM FEMINISM CONSCIOUSNESS WRITING SKILLS SPECIAL
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Morpho-anatomical characterization of Rhododendron subsessile Rendle,an endangered species of the Cordillera Central Range,Philippines
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作者 Mabel Grace V.Bitayan Starleene S.Cervantes Jones T.Napaldet 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第1期241-247,共7页
Conservation of endangered plant species requires a prerequisite basic knowledge of their taxonomy and ecology.Unfortunately in the Cordillera Central Range,several species have not been studied,even though this area ... Conservation of endangered plant species requires a prerequisite basic knowledge of their taxonomy and ecology.Unfortunately in the Cordillera Central Range,several species have not been studied,even though this area harbors a unique type of vegetation not found in other parts of the Philippines.This study documents the morpho-anatomical characteristics of Rhododendron subsessile Rendle,one of the unique and endangered fl ora in the area.The species exhibits a morphology typical of plants in high elevations,being a hardy shrub with small tough leaves,and showy pink fl owers that rival those of commercial rhododendron species.New fi ndings on the species morphology include a variable number of corolla lobes,stamens and a description of its fruits and seeds.The anatomical features of the species are reported here for the fi rst time.The plant exhibits a typical dicot anatomy with dorsiventral leaves,woody stem and root system with the usual arrangement of periderm followed by secondary phloem,vascular cambium,secondary xylem with vessel elements and pith(in the case of the stem).A unique characteristic was identifi ed as the biseriate upper epidermis of the leaf.Documenting themorphological and anatomical features of the species should prove valuable as input baseline information in formulating measures for its conservation. 展开更多
关键词 TAXONOMY Biodiversity conservation Biseriate epidermis Variable stamens
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Small-scale edaphic heterogeneity as a floristic-structural complexity driver in Seasonally Dry Tropical Forests tree communities
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作者 Cle´ber Rodrigo de Souza Jean Daniel Morel +5 位作者 Alisson Borges Miranda Santos Wilder Bento da Silva Vinı´cius Andrade Maia Polyanne Aparecida Coelho Vanessa Leite Rezende Rubens Manoel dos Santos 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第6期2347-2357,共11页
Our work aimed to test the hypothesis that soil microscale heterogeneity act as a community ecological driver,increasing diversity and promoting structural shifts on the Seasonally Dry Tropical Forest(SDTF)tree commun... Our work aimed to test the hypothesis that soil microscale heterogeneity act as a community ecological driver,increasing diversity and promoting structural shifts on the Seasonally Dry Tropical Forest(SDTF)tree community.We evaluated the relationship between microscale edaphic variations and floristic–structural patterns of tree communities in a SDTF fragment located in the southern end of the Brazilian Caatinga domain.Vegetation and soil data were obtained through 27 sample units of 400 m2(20 m 920 m),within each one we measured and identified at species level all arboreal individuals with Circumference at the Breast Height greater or equal to 10 cm,and also collected the soil samples.Through the data we evaluated soil variation influence on the tree community structural and floristic patterns trough generalized linear models.Soil explained the small-scale structural and floristic variations,contributing significantly to biomass,sprouting and to floristic relationships between sample units.It was also observed a possible relation of the result with the Caatinga domain biogeographic history,due the presence of Sedimentary Caatinga species,which are not expected for the study region.Soil plays an important role in driving small-scale complexity and diversity of SDTF,but we also suggest that Caatinga biogeographic events have influence on the high heterogeneity patterns. 展开更多
关键词 Caatinga domain Edaphic variables SPROUTING Sedimentary Caatinga
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