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Impacts of road on plant invasions in the Middle Mountain region of central Nepal
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作者 Ananda ADHIKARI Adarsha SUBEDI +1 位作者 Achyut TIWARI Bharat Babu SHRESTHA 《Journal of Mountain Science》 SCIE CSCD 2024年第2期619-632,共14页
Biological invasion is triggered by human development activities such as the construction and expansion of road networks.Road verges serve as important habitats and corridors for the distribution of invasive alien pla... Biological invasion is triggered by human development activities such as the construction and expansion of road networks.Road verges serve as important habitats and corridors for the distribution of invasive alien plant species(IAPS)between geographically distant habitats.However,the trajectory of plant invasion and the data regarding the impact of roads on IAPS distribution are relatively poor in Nepal.Here,we surveyed two road types(main roads and feeder road)in the Middle Mountain region of central Nepal in order to investigate how different road types are driving the dispersal of IAPS along road verges and the adjacent natural habitats.Systematic sampling was conducted at ca 2.5 km intervals along the roads.At each sampling site,paired plots(25 m×4 m)were sampled:one adjacent to and along the road,and another 20 m away and parallel to it in the interior habitat.Our results revealed that the main road verges had a higher cover(33%)and a larger number of IAPS(14 species)than the feeder road(25%;10 species).The IAPS cover and richness were significantly higher along verges than in the adjacent interior habitats for both road types,indicating that roads are contributing as corridors for the dispersal of IAPS in the Middle Mountain areas of central Nepal.Further,elevation,tree canopy,and disturbances(grazing/mowing/trampling)were found to be the key factors that determine spatial distribution of IAPS along road verges.We emphasize that regular monitoring of vegetation along the road verges can help with the early detection and control of potential IAPS in the region before they become problematic. 展开更多
关键词 Biological invasions Dispersal corridor Invasive alien plants Transport infrastructure Himalayan mountains
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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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Marine invasions enter the genomic era: three lessons from the past, and the way forward 被引量:1
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作者 Frederique VIARD Patrice DAVID John A. DARLING 《Current Zoology》 SCIE CAS CSCD 2016年第6期629-642,共14页
The expanding scale and increasing rate of marine biological invasions have been documented since the early 20th century. Besides their global ecological and economic impacts, non-indigenous species (NIS) also have ... The expanding scale and increasing rate of marine biological invasions have been documented since the early 20th century. Besides their global ecological and economic impacts, non-indigenous species (NIS) also have attracted much attention as opportunities to explore important eco-evolutionary processes such as rapid adaptation, long-distance dispersal and range expansion, and secondary contacts between divergent evolutionary lineages. In this context, genetic tools have been extensively used in the past 20 years. Three important issues appear to have emerged from such studies. First, the study of NIS has revealed unexpected cryptic diversity in what had previously been assumed homogeneous entities. Second, there has been surprisingly little evidence of strong founder events accompanying marine introductions, a pattern possibly driven by large propagule loads. Third, the evolutionary processes leading to successful invasion have been difficult to ascertain due to faint genetic signals. Here we explore the potential of novel tools associated with high-throughput sequencing (HTS) to address these still pressing issues. Dramatic increase in the number of loci accessible via HTS has the potential to radically increase the power of analyses aimed at species delineation, exploring the population genomic consequences of range expansions, and examining evolutionary processes such as admixture, introgression, and adaptation. Nevertheless, the value of this new wealth of genomic data will ultimately depend on the ability to couple it with expanded "traditional" efforts, including exhaustive sampling of marine populations over large geographic scales, integrated taxonomic analyses, and population level exploration of quantitative trait differentiation through common-garden and other laboratory experiments. 展开更多
关键词 biological invasions cryptic species cryptogenic species eco-evolutionary processes genornics metabarcoding
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The Making of English:A Story Of Three Invasions and A Cultural Revolution 被引量:1
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作者 Zhang Jingfeng (Departmentof English,Sanming Teachers College) 《三明学院学报》 2000年第3期48-53,共6页
How come the English language develops into whatwe now call Modern English?This article intends to find outsome of itsorigins and reasonsfrom the pointof wview ofthe historical backgrounds thatresults in the development.
关键词 LANGUAGE HISTORY invasions CHRISTIANITY
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Major Invasions of Britain and Their Influence on English Language
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作者 林岚 《海外英语》 2011年第8X期368-370,372,共4页
British history has been a history of invasion. The birth of English language is a result of invasions of the British Isles over many hundreds of years. Throughout British history there were four major invasions, name... British history has been a history of invasion. The birth of English language is a result of invasions of the British Isles over many hundreds of years. Throughout British history there were four major invasions, namely, the Roman Occupation, the Anglo-Saxon Invasion, the Viking Raids and the Norman Conquest, which had significant influence on English language. 展开更多
关键词 invasions of BRITAIN INFLUENCE ENGLISH LANGUAGE
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DIFFERENCES BETWEEN CAESAR'S TWO INVASIONS OF BRITAIN
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《Journal of Ancient Civilizations》 2001年第1期21-30,共10页
关键词 AS CAESAR DIFFERENCES BETWEEN CAESAR’S TWO invasions OF BRITAIN
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Applications of next-generation sequencing to the study of biological invasions 被引量:5
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作者 Marc RIUS Steve BOURNE +1 位作者 Harry Guy HORNSBY Mark A. CHAPMAN 《Current Zoology》 SCIE CAS CSCD 2015年第3期488-504,共17页
Through the widespread implementation of next-generation sequencing (NGS), analyses of the whole genome (the entire DNA content) and the whole transcriptome (the genes being expressed) are becoming commonplace. ... Through the widespread implementation of next-generation sequencing (NGS), analyses of the whole genome (the entire DNA content) and the whole transcriptome (the genes being expressed) are becoming commonplace. NGS enables the analysis of a vast amount of previously unattainable genetic information. Despite this potential, NGS has yet to be widely imple- mented in genetic studies of biological invasions. The study of the genomic causes and consequences of biological invasions al- lows a deeper understanding of the molecular mechanisms underpinning the invasion process. In this review, we present a brief introduction to NGS followed by a synthesis of current research in the genomics and transcriptomics of adaptation and coloniza- tion. We then highlight research opportunities in the field, including: (1) assembling genomes and transcriptomes of non-model organisms, (2) identifying genomic regions and candidate genes underlying evolutionary processes, and (3) studying the adaptive role of gene expression variation. In particular, because introduced species face a broad range of physiological and biotic chal- lenges when colonizing novel and variable environments, transcriptomics will enable the study of gene regulatory pathways that may be responsible for acclimation or adaptation. To conclude, we identify a number of research approaches that will aid our fu- ture understanding of biological invasions 展开更多
关键词 Exotic species GENOMICS Genotype-environment interactions Invasive species Invasion genetics Invasion route Non-indigenous species Non-native species
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The role of aggression in range expansion and biological invasions 被引量:6
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作者 Sandra HUDINA Karlo HOCK Kresimir ZGANEC 《Current Zoology》 SCIE CAS CSCD 2014年第3期401-409,共9页
Traits that aid in the invasion process should exhibit a gradient across the expansion range in response to changing selection pressures. Aggression has been repeatedly associated with invasion success in many taxa, a... Traits that aid in the invasion process should exhibit a gradient across the expansion range in response to changing selection pressures. Aggression has been repeatedly associated with invasion success in many taxa, as it may help invaders to wrestle the resources from other species which enhances their success in a novel environment. However, aggression primarily al lows individuals to overcome conspecific rivals, providing advantages in competition over resources. Agonistic prowess could therefore increase fitness at both ends of the expansion gradient. Here we review the role of aggression in range expansion of in vasive species, and its potential role as a driver of range expansion. We analyze how these different mechanisms could affect trait variation in expanding and invasive populations. Specifically, we look at how aggression could help dilate the edges of a popula tion through niche competition, as well as lead to exclusion from the center (Le. areas of high population density) by the conspe cities. Both of these processes will result in a characteristic spatial distribution of phenotypes related to aggression that could provide insights into the ecological pressures and dynamics of expanding populations, potentially providing clues to their success as niche competitors and invasive species 展开更多
关键词 AGGRESSION Trait variation Invasion success Invasive species
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Fluctuating resources,disturbance and plant strategies:diverse mechanisms underlying plant invasions 被引量:2
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作者 Ian J RADFORD 《Journal of Arid Land》 SCIE CSCD 2013年第3期284-297,共14页
This paper examines the hypothesis that non-native plant invasions are related to fluctuating resource availability as proposed by Davis et al. (2000). I measured relative functional responses of both invasive and n... This paper examines the hypothesis that non-native plant invasions are related to fluctuating resource availability as proposed by Davis et al. (2000). I measured relative functional responses of both invasive and native plants to changed resource availability due to nutrient enrichment and rainfall, and to increased disturbance. Data are presented from studies in two contrasting ecosystems. First is a series of glasshouse and field experiments on the invader Hieracium lepidulum and associated invasive and native species in subalpine temperate New Zealand. Second is a field study of invasive and native plant responses to altered disturbance regimes and rainfall from tropical savannas of north eastern Australia. Invaders responded differently from native species to changes in resource availability in both subalpine and tropical studies. However, invaders differed among themselves showing that different species exploit different functional niches to invade their respective habitats. These findings contribute to the contention that the fluctuating resource hypothesis does not provide a universal explanation for plant invasions. The diverse functional responses to increased resource availability among invaders in this and previous studies suggest that the cause of invasion depends on unique combinations of habitat and functional attributes of invaders and native assemblages. Such findings imply that universal predictions of what will happen under climate change scenarios across the globe will be difficult to make. 展开更多
关键词 plant invasion plant strategies C-S-R triangle fluctuating resources DISTURBANCE
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Marine Species Introduced on the French Channel-Atlantic Coasts: A Review of Main Biological Invasions and Impacts 被引量:3
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作者 Valérie Stiger-Pouvreau Gérard Thouzeau 《Open Journal of Ecology》 2015年第5期227-257,共31页
The impacts of anthropogenisation modify permanently the distribution patterns of brackish and marine species. Globalization leads to a rapid increase of the numbers of introduced species anywhere in the world. Biolog... The impacts of anthropogenisation modify permanently the distribution patterns of brackish and marine species. Globalization leads to a rapid increase of the numbers of introduced species anywhere in the world. Biological invasions often result in significant losses in the economic value, biological diversity and function of invaded ecosystems. This review presents the main pathways of introduction of non-indigenous species and the main benthic taxonomic groups being established and/or invasive along the French Channel-Atlantic coasts. A focus is put on main invasive marine species in the intertidal and subtidal zones of Brittany (France), among macroalgae (Sargassum muticum, Grateloupia turuturu, Undaria pinnatifida, Codium fragile and Gracilaria vermiculophylla), halophytes (Spartina alterniflora) and benthic invertebrates (Mollusks: Crepidula fornicata, Crassostrea gigas and Venerupis philippinarum). The species biology, introduction vectors, reproductive and dispersal capacities are considered, together with proliferation patterns along the Channel-Atlantic coasts. The ecological impacts of these species on the environment are also described, as well as the European regulations existing to limit alien species introduction and some examples of struggle against the invaders including eradication trials and biomass valorization. Last, the on-going impacts of global changes on alien species invasiveness along the Channel-Atlantic coasts are discussed. 展开更多
关键词 Invasive SPECIES FRENCH Channel-Atlantic Coasts HALOPHYTE MACROALGAE Mollusks IMPACTS Remediation
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Does regional species diversity resist biotic invasions? 被引量:1
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作者 Qinfeng Guo Hong Qian Jian Zhang 《Plant Diversity》 SCIE CAS CSCD 2023年第3期353-357,共5页
The role of regional species diversity in large-scale species invasions has been largely controversial.On the one hand,it has been proposed that diversity may facilitate invasion(“diversity begets diversity”)because... The role of regional species diversity in large-scale species invasions has been largely controversial.On the one hand,it has been proposed that diversity may facilitate invasion(“diversity begets diversity”)because regions with higher diversity may indicate favorable conditions for many more species.On the other hand,high diversity may indicate high levels of niche occupation,thus making it more difficult for new species to invade.In the past,invasion biologists have evaluated how regional native and exotic richness are related.Here,we test whether the range size of exotic species may be constrained by regional native richness using plant data from three continental regions in the Northern Hemisphere,i.e.,Europe,Eastern Asia,and North America.We found that regional native plant diversity is inversely related to the range size of exotic species.This result may be due to stronger species interactions such as competition in species-rich habitats that limit the establishment and spread of exotic species. 展开更多
关键词 COMPETITION Degree of invasion Distribution INVASIBILITY Range size
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Erythrocyte invasions and receptor heterogeneity in field isolates of Nanay river basin Iquitos 被引量:1
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作者 Kuppusamy Chenniappan Sarah H Johns 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2012年第8期589-593,共5页
Objective:To determine whether the requirements for sialic acid varies and whether several types of silaic acid independent receptors utilized for invasion mechanisms of fresh filed isolates collected around Nanay riv... Objective:To determine whether the requirements for sialic acid varies and whether several types of silaic acid independent receptors utilized for invasion mechanisms of fresh filed isolates collected around Nanay river basin,Iquitos.Methods:The field isolates were cultured as described previously by Jensen and Trager and MR4 protocol with little modifications.The erythrocytes preparation and subsequent enzyme treatment was done as described previously by Sharma.with little modification.Invasion assay was performed as described previously by Sharma et al with little modification.Results:The Nanay river basin isolates showed five types of invasion mechanisms or types of receptors-ligand interactions.Here we observed that an equal numbers of neuraminidase sensitive and resistant invasion receptor-ligand interaction profiles as the most common receptor-ligand invasion profiles.Neuraminidase resistance trypsin sensitive chymotrypsin sensitive(NM_RT_SCT_S) invasion of receptor-ligand interaction profile was found in seven isolates,Five field isolates and one reference strain showed neuraminidase sensitive, trypsin sensitive and chymotrypsin resistant(NM_RT_SCT_R) invasion of receptor-ligand interactions, six isolates including one reference strains dd2 showed neuraminidase sensitive,trypsin and chymotrypsin resistance(NM_ST_RCT_R) indicating its dependence on sialic acids and independence of trypsin and chymotrypsin sensitive proteins.Four isolates showed neuraminidase sensitive, trypsin sensitive and chymotrypsin sensitive(NM_ST_SCT_S) invasion of receptor-ligand interactions, seven isolates were neuraminidase resistant,trypsin sensitive and chymotrypsin resistance (NM_RT_SCT_R) invasion of receptor-ligand interactions,indicating its dependence on trypsin sensitive proteins.Conclusions:The Nanay river basin isolates showed five types of invasion mechanisms or types of receptors-ligand interactions.A full understanding of theses invasion mechanisms may allow the development of novel prophylactic and therapeutic strategies that block erythrocyte receptor-ligand invasion mechanisms. 展开更多
关键词 Nanay river basin INVASION Sialic acid PLASMODIUM FALCIPARUM MALARIA
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A multi-scale modelling framework to guide management of plant invasions in a transboundary context
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作者 Joao Martins David M.Richardson +6 位作者 Renato Henriques Elizabete Marchante Hélia Marchante Paulo Alves Mirijam Gaertner Joao P.Honrado Joana R.Vicente 《Forest Ecosystems》 SCIE CSCD 2016年第4期297-310,共14页
Background:Attention has recently been drawn to the issue of transboundary invasions,where species introduced and naturalized in one country cross international borders and become problematic in neighbouring countrie... Background:Attention has recently been drawn to the issue of transboundary invasions,where species introduced and naturalized in one country cross international borders and become problematic in neighbouring countries.Robust modelling frameworks,able to identify the environmental drivers of invasion and forecast the current and future potential distribution of invasive species,are needed to study and manage invasions.Limitations due to the lack of species distribution and environmental data,or assumptions of modelling tools,often constrain the reliability of model predictions.Methods:We present a multiscale spatial modelling framework for transboundary invasions,incorporating robust modelling frameworks(Multimodel Inference and Ensemble Modelling) to overcome some of the limitations.The framework is illustrated using Hakea sericea Schrad.(Proteaceae),a shrub or small tree native to Australia and invasive in several regions of the world,including the Iberian Peninsula.Two study scales were considered:regional scale(western Iberia,including mainland Portugal and Galicia) and local scale(northwest Portugal).At the regional scale,the relative importance of environmental predictors sets was evaluated and ranked to determine the main general drivers for the species distribution,while the importance of each environmental predictor was assessed at the local scale.The potential distribution of H.sericea was spatially projected for both scale areas.Results:Model projections for western Iberia suggest that a large area is environmentally suitable in both Portugal and Spain.Climate and landscape composition sets were the most important determinants of this regional distribution of the species.Conversely,a geological predictor(schist lithology) was more important in explaining its local-scale distribution.Conclusions:After being introduced to Portugal,H.sericea has become a transboundary invader by expanding in parts of Galicia(Spain).The fact that a larger area is predicted as environmentally suitable in Spain raises concerns regarding its potential continued expansion.This highlights the importance of transboundary cooperation in the early management of invasions.By reliably identifying drivers and providing spatial projections of invasion at multiple scales,this framework provides insights for the study and management of biological invasions,including the assessment of transboundary invasion risk. 展开更多
关键词 Drivers of invasion Hakea sericea Multimodel inference Transboundary invasion management Species distribution models
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Use of GIS to Determine Potential Sources of Aquatic Invasive Species Invasions into Western South Dakota Reservoirs
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作者 Jayne Kylee Ecker Ryan Raben Greg Simpson 《Natural Resources》 2020年第2期39-45,共7页
The spread of Aquatic Invasive Species (AIS) is a constant threat for western US waters. The state of South Dakota detected zebra mussels (Dreissena polymorpha) for the first time at Lewis and Clark Reservoir in 2014.... The spread of Aquatic Invasive Species (AIS) is a constant threat for western US waters. The state of South Dakota detected zebra mussels (Dreissena polymorpha) for the first time at Lewis and Clark Reservoir in 2014. Since then, efforts have been towards preventing their further expansion. To determine possible avenues of infestation westward, we used ArcGIS to map the home zip codes of boaters using four western reservoirs (Belle Fourche Reservoir, Pactola Reservoir, Sheridan Lake and Angostura Reservoir). A 60-mile buffer was used to determine spatial relationships of boater zip codes to establish zebra mussel populations and was considered areas of high risk. We found that there were three instances where a boater came from a high-risk area during the study period. Our results show possible pathways for Dreissena expansion into western South Dakota reservoirs. Most notably is that exposure can occur from either an inter- or intra-state vector. This information confirmed that there is a risk of additional water bodies in South Dakota becoming infected. Based on past studies, prevention is the best method in slowing the expansion of zebra mussels in South Dakota. We suggest three actions, strategically placed decontamination stations, continued public awareness efforts and differentiating boat registration tags on watercraft that are near infested water bodies. 展开更多
关键词 GIS SOUTH Dakota INVASIVE Species ZEBRA MUSSEL
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Plant invasions facilitated by suppression of root nutrient acquisition rather than by disruption of mycorrhizal association in the native plant
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作者 Jing Chen Hai-Yan Zhang +2 位作者 Ming-Chao Liu Mei-Xu Han De-Liang Kong 《Plant Diversity》 SCIE CAS CSCD 2022年第5期499-504,共6页
Invasive species have profound negative impacts on native ranges.Unraveling the mechanisms employed by invasive plant species is crucial to controlling invasions.One important approach that invasive plants use to outc... Invasive species have profound negative impacts on native ranges.Unraveling the mechanisms employed by invasive plant species is crucial to controlling invasions.One important approach that invasive plants use to outcompete native plants is to disrupt mutualistic interactions between native roots and mycorrhizal fungi.However,it remains unclear how differences in the competitive ability of invasive plants affect native plant associations with mycorrhizae.Here,we examined how a native plant,Xanthium strumarium,responds to invasive plants that differed in competitive abilities(i.e.,as represented by aboveground plant biomass)by measuring changes in root nitrogen concentration(root nutrient acquisition)and mycorrhizal colonization rate.We found that both root nitrogen concentration and mycorrhizal colonization rate in the native plant were reduced by invasive plants.The change in mycorrhizal colonization rate of the native plant was negatively correlated with both aboveground plant biomass of the invasive plants and the change in aboveground plant biomass of the native plant in monocultures relative to mixed plantings.In contrast,the change in root nitrogen concentration of the native plant was positively correlated with aboveground plant biomass of the invasive plants and the change in aboveground plant biomass of the native plant.When we compared the changes in mycorrhizal colonization rate and root nitrogen concentration in the native plant grown in monocultures with those of native plants grown with invasive plants,we observed a significant tradeoff.Our study shows that invasive plants can suppress native plants by reducing root nutrient acquisition rather than by disrupting symbiotic mycorrhizal associations,a novel finding likely attributable to a low dependence of the native plant on mycorrhizal fungi. 展开更多
关键词 Plant invasion Root strategy Mycorrhizal strategy Tradeoff
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BIOLOGICAL INVASION PROBLEM WITH FREE BOUNDARY NONLOCAL DIFFUSION EQUATION 被引量:2
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作者 HE Yu-rong ZHANG Ya-rong 《数学杂志》 2025年第1期48-56,共9页
In order to better describe the phenomenon of biological invasion,this paper introduces a free boundary model of biological invasion.Firstly,the right free boundary is added to the equation with logistic terms.Secondl... In order to better describe the phenomenon of biological invasion,this paper introduces a free boundary model of biological invasion.Firstly,the right free boundary is added to the equation with logistic terms.Secondly,the existence and uniqueness of local solutions are proved by the Sobolev embedding theorem and the comparison principle.Finally,according to the relevant research data and contents of red fire ants,the diffusion area and nest number of red fire ants were simulated without external disturbance.This paper mainly simulates the early diffusion process of red fire ants.In the early diffusion stage,red fire ants grow slowly and then spread over a large area after reaching a certain number. 展开更多
关键词 Free boundary biological invasion differential equation
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Immunohistochemical expression of matrix metalloproteinase-9 and 13 in oral squamous cell carcinoma and their role in predicting lymph node metastasis 被引量:1
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作者 Bhari Sharanesha Manjunatha Keshav T Handge +2 位作者 Vandana Sandeep Shah Yasser Eid Al-Thobaiti Deepak Gowda Sadashivappa Pateel 《World Journal of Methodology》 2025年第2期108-116,共9页
BACKGROUND One of the main characteristics of oral squamous cell carcinoma(OSCC)is that it metastasizes to cervical lymph nodes frequently with a high degree of local invasiveness.A primary feature of malignant tumors... BACKGROUND One of the main characteristics of oral squamous cell carcinoma(OSCC)is that it metastasizes to cervical lymph nodes frequently with a high degree of local invasiveness.A primary feature of malignant tumors is their penetration of neighboring tissues,such as lymphatic and blood arteries,due to the tumor cells'capacity to break down the extracellular matrix(ECM).Matrix metalloproteinases(MMPs)constitute a family of proteolytic enzymes that facilitate tissue remodeling and the degradation of the ECM.MMP-9 and MMP-13 belong to the group of extracellular matrix degrading enzymes and their expression has been studied in OSCC because of their specific functions.MMP-13,a collagenase family member,is thought to play an essential role in the MMP activation cascade by breaking down the fibrillar collagens,whereas MMP-9 is thought to accelerate the growth of tumors.Elevated MMP-13 expression has been associated with tumor behavior and patient prognosis in a number of malignant cases.AIM To assess the immunohistochemical expression of MMP-9 and MMP-13 in OSCC.METHODS A total of 40 cases with histologically confirmed OSCC by incisional biopsy were included in this cross-sectional retrospective study.The protocols for both MMP-9 and MMP-13 immunohistochemical staining were performed according to the manufacturer’s recommendations along with the normal gingival epithelium as a positive control.All the observations were recorded and Pearson’sχ²test with Fisher exact test was used for statistical analysis.RESULTS Our study showed no significant correlation between MMP-9 and MMP-13 staining intensity and tumor size.The majority of the patients were in advanced TNM stages(III and IV),and showed intense expression of MMP-9 and MMP-13.CONCLUSION The present study suggests that both MMP-9 and MMP-13 play an important and independent role in OSCC progression and invasiveness.Intense expression of MMP-9 and MMP-13,irrespective of histological grade of OSCC,correlates well with TNM stage.Consequently,it is evident that MMP-9 and MMP-13 are important for the invasiveness and progression of tumors.The findings may facilitate the development of new approaches for evaluating lymph node metastases and interventional therapy techniques,hence enhancing the prognosis of patients diagnosed with OSCC. 展开更多
关键词 Matrix metalloproteinases Oral squamous cell carcinoma Tumor staging IMMUNOHISTOCHEMISTRY INVASION Lymph node metastasis TNM stage
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Tongue squamous cell carcinoma-targeting Au-HN-1 nanosystem for CT imaging and photothermal therapy 被引量:1
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作者 Ming Hao Xingchen Li +11 位作者 Xinxin Zhang Boqiang Tao He Shi Jianing Wu Yuyang Li Xiang Li Shuangji Li Han Wu Jingcheng Xiang Dongxu Wang Weiwei Liu Guoqing Wang 《International Journal of Oral Science》 2025年第1期112-121,共10页
Tongue squamous cell carcinoma(TSCC)is a prevalent malignancy that afflicts the head and neck area and presents a high incidence of metastasis and invasion.Accurate diagnosis and effective treatment are essential for ... Tongue squamous cell carcinoma(TSCC)is a prevalent malignancy that afflicts the head and neck area and presents a high incidence of metastasis and invasion.Accurate diagnosis and effective treatment are essential for enhancing the quality of life and the survival rates of TSCC patients.The current treatment modalities for TSCC frequently suffer from a lack of specificity and efficacy.Nanoparticles with diagnostic and photothermal therapeutic properties may offer a new approach for the targeted therapy of TSCC.However,inadequate accumulation of photosensitizers at the tumor site diminishes the efficacy of photothermal therapy(PTT).This study modified gold nanodots(AuNDs)with the TSCC-targeting peptide HN-1 to improve the selectivity and therapeutic effects of PTT.The Au-HN-1 nanosystem effectively targeted the TSCC cells and was rapidly delivered to the tumor tissues compared to the AuN Ds.The enhanced accumulation of photosensitizing agents at tumor sites achieved significant PTT effects in a mouse model of TSCC.Moreover,owing to its stable long-term fluorescence and high X-ray attenuation coefficient,the Au-HN-1 nanosystem can be used for fluorescence and computed tomography imaging of TSCC,rendering it useful for early tumor detection and accurate delineation of surgical margins.In conclusion,Au-HN-1 represents a promising nanomedicine for imaging-based diagnosis and targeted PTT of TSCC. 展开更多
关键词 DIAGNOSIS SQUAMOUS INVASION
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Analgesic effect and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive inguinal hernia surgery 被引量:1
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作者 Qian-Xing Lou Ke-Ping Xu 《World Journal of Gastrointestinal Surgery》 2025年第3期161-170,共10页
BACKGROUND Currently,very few studies have examined the analgesic effectiveness and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive surgery for ... BACKGROUND Currently,very few studies have examined the analgesic effectiveness and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive surgery for inguinal hernia.AIM To investigate the analgesic effect and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive surgery for inguinal hernia.METHODS In this retrospective study,94 patients scheduled for laparoscopic minimally invasive surgery for inguinal hernia,admitted to Yiwu Central Hospital between May 2022 and May 2023,were divided into a control group(inhalation combined general anesthesia)and a treatment group(dexmedetomidine-assisted intrave-nous-inhalation combined general anesthesia).Perioperative indicators,analgesic effect,preoperative and postoperative 24-hours blood pressure(BP)and heart rate(HR),stress indicators,immune function levels,and adverse reactions were com-pared between the two groups.RESULTS Baseline data,including age,hernia location,place of residence,weight,monthly income,education level,and underlying diseases,were not significantly different between the two groups,indicating comparability(P>0.05).No significant difference was found in operation time and anesthesia time between the two groups(P>0.05).However,the treatment group exhibited a shorter postoperative urinary catheter removal time and hospital stay than the control group(P<0.05).Preoperatively,no significant differences were found in the visual analog scale(VAS)scores between the two groups(P>0.05).However,at 12,18,and 24 hours postoper-atively,the treatment group had significantly lower VAS scores than the control group(P<0.05).Although no significant differences in preoperative hemodynamic indicators were found between the two groups(P>0.05),both groups experienced some extent of changes in postoperative HR,diastolic BP(DBP),and systolic BP(SBP).Nevertheless,the treatment group showed smaller changes in HR,DBP,and SBP than the control group(P<0.05).Preoperative immune function indicators showed no significant differences between the two groups(P>0.05).However,postoperatively,the treatment group demonstrated higher levels of CD3+,CD4+,and CD4+/CD8+and lower levels of CD8+than the control group(P<0.05).The rates of adverse reactions were 6.38%and 23.40%in the treatment and control groups,respectively,revealing a significant difference(χ2=5.371,P=0.020).CONCLUSION Dexmedetomidine-assisted intravenous-inhalation combined general anesthesia can promote early recovery of patients undergoing laparoscopic minimally invasive surgery for inguinal hernia.It ensures stable blood flow,improves postoperative analgesic effects,reduces postoperative pain intensity,alleviates stress response,improves immune function,facilitates anesthesia recovery,and enhances safety. 展开更多
关键词 DEXMEDETOMIDINE Intravenous-inhalation combined general anesthesia Inguinal hernia Laparoscopic minimally invasive surgery Analgesia SAFETY
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Magnetic resonance imaging bias field correction improves tumor prognostic evaluation after transcatheter arterial chemoembolization for liver cancer 被引量:1
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作者 Ke Liu Jun-Biao Li +1 位作者 Yong Wang Yan Li 《World Journal of Gastrointestinal Surgery》 2025年第4期207-220,共14页
BACKGROUND Transcatheter arterial chemoembolization(TACE)is a key treatment approach for advanced invasive liver cancer(infiltrative hepatocellular carcinoma).However,its therapeutic response can be difficult to evalu... BACKGROUND Transcatheter arterial chemoembolization(TACE)is a key treatment approach for advanced invasive liver cancer(infiltrative hepatocellular carcinoma).However,its therapeutic response can be difficult to evaluate accurately using conventional two-dimensional imaging criteria due to the tumor’s diffuse and multifocal growth pattern.Volumetric imaging,especially enhanced tumor volume(ETV),offers a more comprehensive assessment.Nonetheless,bias field inhomogeneity in magnetic resonance imaging(MRI)poses challenges,potentially skewing volumetric measurements and undermining prognostic evaluation.AIM To investigate whether MRI bias field correction enhances the accuracy of volumetric assessment of infiltrative hepatocellular carcinoma treated with TACE,and to analyze how this improved measurement impacts prognostic prediction.METHODS We retrospectively collected data from 105 patients with invasive liver cancer who underwent TACE treatment at the Affiliated Hospital of Xuzhou Medical University from January 2020 to January 2024.The improved N4 bias field correction algorithm was applied to process MRI images,and the ETV before and after treatment was calculated.The ETV measurements before and after correction were compared,and their relationship with patient prognosis was analyzed.A Cox proportional hazards model was used to evaluate prognostic factors,with Martingale residual analysis determining the optimal cutoff value,followed by survival analysis.RESULTS Bias field correction significantly affected ETV measurements,with the corrected baseline ETV mean(505.235 cm^(3))being significantly lower than before correction(825.632 cm^(3),P<0.001).Cox analysis showed that the hazard ratio(HR)for corrected baseline ETV(HR=1.165,95%CI:1.069-1.268)was higher than before correction(HR=1.063,95%CI:1.031-1.095).Using 412 cm^(3) as the cutoff,the group with baseline ETV<415 cm^(3) had a longer median survival time compared to the≥415 cm^(3) group(18.523 months vs 8.926 months,P<0.001).The group with an ETV reduction rate≥41%had better prognosis than the<41%group(17.862 months vs 9.235 months,P=0.006).Multivariate analysis confirmed that ETV reduction rate(HR=0.412,P<0.001),Child-Pugh classification(HR=0.298,P<0.001),and Barcelona Clinic Liver Cancer stage(HR=0.578,P=0.045)were independent prognostic factors.CONCLUSION Volume imaging based on MRI bias field correction can improve the accuracy of evaluating the efficacy of TACE treatment for invasive liver cancer.The corrected ETV and its reduction rate can serve as independent indicators for predicting patient prognosis,providing important reference for developing individualized treatment strategies. 展开更多
关键词 Invasive liver cancer Transcatheter arterial chemoembolization Magnetic resonance imaging Bias field correction Volume imaging
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