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Microglia and brain macrophages are differentially associated with tumor necrosis in glioblastoma:A link to tumor progression
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作者 CHRISTINA LOH YUQI ZHENG +8 位作者 ISLAM ALZOUBI KIMBERLEY L.ALEXANDER MAGGIE LEE WEI-DONG CAI YANG SONG KERRIE MCDONALD ANNA K.NOWAK RICHARD B.BANATI MANUEL B.GRAEBER 《Oncology Research》 2025年第4期937-950,共14页
Background:Microglia and brain macrophages contribute significantly to the tumor microenvironment in highly malignant glioblastoma where they are considered important drivers of tumor progression.A better understandin... Background:Microglia and brain macrophages contribute significantly to the tumor microenvironment in highly malignant glioblastoma where they are considered important drivers of tumor progression.A better understanding of the role of the brain macrophages present in glioblastoma appears crucial for improving therapeutic outcomes,especially in the context of novel immunotherapeutic approaches.Methods:We investigated the regulation of two well-established markers for microglia and brain macrophages,IBA1 and CD163,in relation to glioblastoma tumor necrosis using immunohistochemistry and modality fusion heatmaps of whole slide images obtained from adjacent tissue sections.Results:IBA1 and CD163 showed remarkable differences in relation to glioblastoma tumor necrosis.Generally,IBA1 immunoreactive cells were far less common in necrotic tissue areas than CD163-expressing cells.We also found extensive and frequently diffuse extracellular CD163 deposition,especially in hypocellular necrobiotic tumor regions where IBA1 was typically absent.Conclusions:Resident microglia seem more likely to be important for the diffuse infiltration of glioma cells in hypercellular tissue areas,whereas myeloid macrophages may be the main macrophage population in the wake of tumor necrosis.Since the necrotic niche with its interactions between microglia,brain macrophages,and glioblastoma/glioma stem cells is increasingly recognised as an important factor in tumor progression,further detailed studies of the macrophage populations in glioblastoma are warranted. 展开更多
关键词 Bone marrow-derived macrophages(BMDM) CD163 Glioblastoma/glioma stem cells(GSCs) IBA1 MICROGLIA Multimodal whole slide analysis Tumor microenvironment
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Job burnout among critical care nurses in the eastern province of Saudi Arabia 被引量:1
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作者 Mahmoud Abdel Hameed Shahin 《Frontiers of Nursing》 2025年第1期67-78,共12页
Objectives:Nurses working in critical care units may encounter substantial work-related strain,and elevated levels of stress can lead to burnout,ultimately impacting both the quality of nursing care and their overall ... Objectives:Nurses working in critical care units may encounter substantial work-related strain,and elevated levels of stress can lead to burnout,ultimately impacting both the quality of nursing care and their overall working experience.This study aimed to assess job burnout and determine the factors that contribute to it among critical care nurses in the Eastern Province of Saudi Arabia.Methods:This study employed a descriptive,exploratory,cross-sectional research design.A total of 220 nurses employed in the critical care units of 5 private hospitals in the eastern region were selected for participation in this study using a convenience sample method.An electronic survey was distributed to critical care nurses in the Eastern Province who satisfied the specified inclusion criteria.The job burnout questionnaire utilized in this study was derived from previously conducted research,which has been established as a reliable and valid survey instrument.The process of data analysis was conducted utilizing the SPSS program.The scientific research conducted on human subjects adhered rigorously to all ethical considerations.Results:The highest percentage of nurses at the critical care units reported experiencing moderate levels of job burnout.Nurses exhibiting greater levels of professional experience demonstrated a statistically significant reduction in overall burnout scores when compared to their less experienced counterparts.Furthermore,within the realm of sociodemographic factors,it was found that the only significant independent predictor for job burnout was the level of experience among critical care nurses.Conclusions:The prevalence of burnout among nurses in critical care settings was found to be significant,with most participants reporting moderate levels of burnout which can yield significant ramifications for nurses and healthcare professionals.Consequently,healthcare organizations must accord primacy to the welfare of their staff and adopt proactive strategies to mitigate job burnout. 展开更多
关键词 critical care eastern province job burnout nurses PREDICTORS Saudi Arabia
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Potential benefits of Nigella Sativa(black seeds)in the management of“Chandipura virus infection”–an insight
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作者 Naina Mohamed Pakkir Maideen 《Food and Health》 2025年第2期3-14,共12页
The Chandipura vesiculovirus(CHPV),a single-stranded,negative sense RNA arbovirus with five structural proteins-the G,N,M,P,and L proteins-is the source of Chandipura virus infection.Children between the ages of 9 mon... The Chandipura vesiculovirus(CHPV),a single-stranded,negative sense RNA arbovirus with five structural proteins-the G,N,M,P,and L proteins-is the source of Chandipura virus infection.Children between the ages of 9 months and 14 years old are the most common recipients of CHPV infection,which is primarily spread by sand flies(Sergentomyia,Phlebotomus species).The potential advantages of black seeds(N.sativa)in the treatment of patients with CHPV infection are the main topic of our current review.The majority of patients infected with CHPV experience neurological complications such as encephalitis and other neurological complications.Since there is currently no approved antiviral treatment,supportive care and symptomatic therapy are the primary methods used to manage CHPV-infected patients.Herbal candidates possessing antioxidant,immunomodulatory,antiviral,and anti-inflammatory qualities may aid in the treatment of CHPV infection.The antiviral,anti-inflammatory,antioxidant,and immunomodulatory qualities of black seeds(N.sativa)have been shown in a number of preclinical and clinical investigations;these attributes could be helpful in the treatment of CHPV infection.Black seeds(N.sativa)may help treat CHPV-infected patients in the early stages of their illness when used in conjunction with symptomatic therapy and supportive care.In patients infected with CHPV,additional randomized controlled clinical trials would assess the efficacy and safety of black seeds(N.sativa). 展开更多
关键词 Chandipura virus ENCEPHALITIS Nigella Sativa black seeds black cumin seeds THYMOQUINONE antiviral anti-inflammatory antioxidant IMMUNOMODULATORY
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Influence of testbed characteristics on community resilience using agent-based modeling
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作者 Xu Han Maria Koliou 《Resilient Cities and Structures》 2025年第2期69-83,共15页
There has been a large increase in the number of days per year with numerous EF1-EF5 tornadoes.Given the significant damage incurred by tornadoes upon communities,community resilience analyses for tornado-stricken com... There has been a large increase in the number of days per year with numerous EF1-EF5 tornadoes.Given the significant damage incurred by tornadoes upon communities,community resilience analyses for tornado-stricken communities have been gaining momentum.As the community resilience analysis aims to guide how to lay out effective hazard mitigation strategies to decrease damage and improve recovery,a comprehensive and accurate approach is necessary.Agent-based modeling,an analysis approach in which different types of agents are created with their properties and behavior clearly defined to simulate the processes of those agents in an external environ-ment,is the most comprehensive and accurate approach so far to conducting community resilience simulations and investigating the decision-making for mitigation and recovery under natural hazards.In this paper,agent-based models(ABMs)are created to simulate the recovery process of a virtual testbed based on the real-world community in Joplin City,MO.The tornado path associated with the real-world tornado event that occurred in May 2011 is adopted in the tornado hazard modeling for the Joplin testbed.In addition,agent-based models are created for another virtual community in the Midwest United States named Centerville using an assumed tornado scenario of the same EF-scale as that in Joplin.The effects of hazard mitigation strategies on the two communities are also explored.A comparison between the analysis results of these two testbeds can indicate the influence of the characteristics of a tornado-prone community on the resilience of the community as well as on the effects of hazard mitigation strategies.It is observed that a community’s level of development significantly impacts the tornado resilience.In addition,the effects of a specific type of hazard mitigation strategy on the recovery process are contingent upon testbed characteristics. 展开更多
关键词 Community resilience agent-based model(ABM) TORNADO Hazard mitigation strategy Testbed characteristics
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Prevalence and Associated Factors of Diabetes Mellitus in Benin
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作者 Alphonse Kpozehouen Francois Djrolo +6 位作者 Charles J.Sossa Akpa R.Gbary Yessito Chouehanou Dieudonné Fambo Yessouf Tchabi Roger Salamon Dismand S. Houinato 《Open Journal of Epidemiology》 2015年第3期163-171,共9页
Background: Data on diabetes mellitus in general population in Benin is scarce. This study aimed therefore to assess prevalence and risk factors of diabetes mellitus in Benin. Methods: The study consisted of a cross-s... Background: Data on diabetes mellitus in general population in Benin is scarce. This study aimed therefore to assess prevalence and risk factors of diabetes mellitus in Benin. Methods: The study consisted of a cross-sectional survey, using the World Health Organisation (WHO)’s instrument for stepwise surveillance (STEPS) of non-communicable diseases risk factors. A five-stage random sample of 25 to 64 years old male and female adults living in Benin participated in structured interviews and their size, weight and blood pressure were measured according to standardized procedures. Glycaemia was measured using ACCUTREND? test strips for capillary blood glucose. Prevalence and means were computed with their 95% confidence interval and standard error respectively, taking into account the sampling design. Prevalence was compared by Khi2 and means by Student’s t test. Univariate and multivariate logistic regressions were performed to identify socio-demographic diabetes’s risk factors. Results: A total of 3772 adults participated in the study. The average age of respondents was 44.2 years. Overall, 68.3% of subjects were illiterate, 82.4% lived in rural areas, 82.57% were self-employed, 20% overweight, 7.51% obese and the prevalence of hypertension was 29.5 p.100. The prevalence of diabetes mellitus was 1.4 p.100 [CI95% = (0.94:2.05)]. This prevalence was higher in men than in women (2.1% vs. 0.8%, p = 0.0031). This prevalence was higher in urban areas than in rural areas. The Littoral department had the highest prevalence (3.4%), followed by the Collines department (2.7%), Donga (2.4%) and Borgou (2.3%). As many as 49.3% of subjects diagnosed with diabetes mellitus were not aware of their status. The age group of 56 - 64 years had the highest risk [OR = 6.6, IC95% = (1.6;22.4)]. The risk of diabetes was higher in people living in urban areas than in people living in rural areas [OR = 3.04 CI95% = (1.6;6.0)]. After controlling for confounding factors, risk factors of diabetes were gender, men being more at risk than women (p = 0.002) age from 55 to 64 years (p = 0.009), overweight (p < 0.0001) and obesity (p = 0.002). Conclusion: Our findings suggested that diabetes mellitus was common in Benin. The prevalence of diabetes is more likely to increase in regard to the nutritional transitions (diet) and the accelerating urbanization of Benin. Communication campaigns for behavioral change are needed to slow down or even reverse this trend. 展开更多
关键词 PREVALENCE Risk Factors Diabetes Mellitus BENIN
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Investigation of effects of hazard geometry and mitigation strategies on community resilience under tornado hazards using an Agent-based modeling approach 被引量:1
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作者 Xu Han Maria Koliou 《Resilient Cities and Structures》 2024年第2期1-19,共19页
A large number of communities are impacted annually by the increasing frequency of tornado hazards resulting in damage to the infrastructure as well as disruption of community functions.The effect of the hazard geomet... A large number of communities are impacted annually by the increasing frequency of tornado hazards resulting in damage to the infrastructure as well as disruption of community functions.The effect of the hazard geometry(center and angle of tornado path as well as the tornado width)is studied herein on how it influences the recovery of physical and social systems within the community.Given that pre-disaster preparedness including mitigation strategies(e.g.,retrofits)and policies(e.g.,insurance)is crucial for increasing the resilience of the community and facilitating a faster recovery process,in this study,the impact of various mitigation strategies and policies on the recovery trajectory and resilience of a typical US community subjected to a tornado is investigated considering different sources of uncertainties.The virtual testbed of Centerville is selected in this paper and is modeled by adopting the Agent-based modeling(ABM)approach which is a powerful tool for conducting community resilience analysis that simulates the behavior of different types of agents and their interactions to capture their interdependencies.The results are presented in the form of recovery time series as well as calculated resilience indices for various community systems(lifeline networks,schools,healthcare,businesses,and households).The results of this study can help deepen our understanding of how to efficiently expedite the recovery process of a community. 展开更多
关键词 Community resilience Agent-based modeling(ABM) TORNADO Mitigation strategy
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Recent Advancements in the Development of Self Healing Concrete-A Systematic Review
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作者 A Ravi Theja M Srinivasula Reddy +1 位作者 Bharat Bhushan Jindal C Sashidhar 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1449-1460,共12页
Mechanical as well as durability properties are pivotal for any type of concrete which gets adversely affected due to cracks that may form due to loading beyond its capacity.Concrete has the intrinsic property to heal... Mechanical as well as durability properties are pivotal for any type of concrete which gets adversely affected due to cracks that may form due to loading beyond its capacity.Concrete has the intrinsic property to heal itself to some extent but not fully as the passive form of autogenous healing plays an inferior role for a complete repair of a cementitious material.The self-healing capabilities can be enhanced by adding chemical admixtures,polymers,and bacteria strains induced calcium carbonate precipitation,etc.In this paper,the advancements in the development and performance of self-healing concrete using chemical admixtures,polymers,and bacteria strains are reviewed.This systematic review includes the available experimental tests and methodologies investigating self-healing efficiency over the last decade.Further,this review focussed on self-healing materials,the ideology,and opinions of those in the construction field on the direction of self-healing concrete for future applications.It is yet not possible to predict the most appropriate technique,however,a generalized opinion about the effectiveness of the different approaches has been illustrated. 展开更多
关键词 SELF-HEALING cracks bio-based healing chemical additives-based healing
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Effect of No Tillage and Conventional Tillage on Wheat Grain Yield Variability: A Review
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作者 Kenza Kadiri Hassani Moussadek Rachid +4 位作者 Baghdad Bouamar Zouahri Abdelmjid Dakak Houria Maher Hassnae Bouabdli Abdelhak 《Journal of Environmental & Earth Sciences》 CAS 2024年第1期57-70,共14页
Conservation Agriculture(CA)covers more than 205 million hectares in the world.This made it possible to face and mitigate the challenges of climate change,reducing soil erosion and providing multiple ecosystem service... Conservation Agriculture(CA)covers more than 205 million hectares in the world.This made it possible to face and mitigate the challenges of climate change,reducing soil erosion and providing multiple ecosystem services.The first elementary factor influenced is the yield evaluation.It has a direct effect on farmers’choices for sustainable production.The present article records a review focused on wheat yield average positive change compared between conventional tillage(CT)and no tillage(NT)systems.The international database collected showed that NT is adaptable everywhere.The results of wheat yield differentiation showed the influence of crop rotation depending on stations located in different climatic zones.In more than 40 years of research,specialists have succeeded in demonstrating the importance of crop productivity like wheat.The whole integrates also experimentations where the initiation starts more than ten years. 展开更多
关键词 Climate change No tillage Crop rotation WHEAT YIELD
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Fuzzy-based approach to quantify the downtime of buildings in developing countries
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作者 Melissa De Iuliis Rayehe Khaghanpour-Shahrezaee +1 位作者 Gian Paolo Cimellaro Mohammad Khanmohammadi 《Resilient Cities and Structures》 2024年第1期1-19,共19页
Earthquake is one of the natural disasters that affects the buildings and communities in developing countries.It causes different levels of damages to the buildings,making them uninhabitable for a period of time,calle... Earthquake is one of the natural disasters that affects the buildings and communities in developing countries.It causes different levels of damages to the buildings,making them uninhabitable for a period of time,called downtime(DT).This paper proposes a Fuzzy Logic hierarchical method to estimate the downtime of residential buildings in developing countries after an earthquake.The use of expert-based systems allows quantifying the indicators involved in the model using descriptive knowledge instead of hard data,accounting also for the un-certainties that may affect the analysis.The applicability of the methodology is illustrated using the information gathered after the 2015 Gorkha,Nepal,earthquake as a case study.On April 25,2015,Nepal was hit by the Mw 7.8 Gorkha earthquake,which damaged and destroyed more than 500.000 residential buildings.Information obtained from a Rapid Visual Damage Assessment(RVDA)is used through a hierarchical scheme to evaluate the building damageability.Sensitivity analysis based on Sobol method is implemented to evaluate the impor-tance of parameters gathered in the RVDA for building damage estimation.The findings of this work may be used to estimate the restoration time of damaged buildings in developing countries and to plan preventive safety measures. 展开更多
关键词 RESILIENCE DOWNTIME Developing countries BUILDINGS Fuzzy logic
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基于LabVIEW的苹果擦伤分级系统设计 被引量:9
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作者 高晓阳 Paul H Heinemann Joseph Irudayaraj 《农业机械学报》 EI CAS CSCD 北大核心 2006年第4期152-154,共3页
基于美国USDA苹果分级标准研制了苹果擦伤检测分级系统样机。系统依据所研究的苹果表面擦伤拉曼光谱PLS/CVA处理和UNEQ模型分类,通过设计的LabVIEW虚拟仪器控制系统实时完成苹果分级。对48个预先分级的美国红元帅苹果(reddelicious#4167... 基于美国USDA苹果分级标准研制了苹果擦伤检测分级系统样机。系统依据所研究的苹果表面擦伤拉曼光谱PLS/CVA处理和UNEQ模型分类,通过设计的LabVIEW虚拟仪器控制系统实时完成苹果分级。对48个预先分级的美国红元帅苹果(reddelicious#4167)分别进行两轮实际分级实验来评估该系统的性能。实验结果表明该分级检测系统对无擦伤、轻擦伤和重擦伤苹果组的分级平均准确率分别为100%、99%、97%。分级系统每分钟可分级苹果3~6个,对运动苹果分级误判率较低,是实施苹果自动检测分级生产线的基本模块。 展开更多
关键词 苹果 分级系统 擦伤 拉曼光谱 虚拟仪器
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佛罗里达州柑桔投资的远景展望——GAMS仿真的案例(英文)
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作者 陈秉钧 Spreen Tom H Moss Charles B 《农业工程学报》 EI CAS CSCD 北大核心 1995年第2期42-47,共6页
运用GAMS仿真展示了美国佛罗里达州柑桔生产投资的经济远景。仿真动态地、定量地回答了长期投资决策中的五个关键因素:期望净投资回收率、最低竞争价格、最大可接受的贷款利率、新建桔园的最优种植计划、最早获得盈利的年份(以净现值为... 运用GAMS仿真展示了美国佛罗里达州柑桔生产投资的经济远景。仿真动态地、定量地回答了长期投资决策中的五个关键因素:期望净投资回收率、最低竞争价格、最大可接受的贷款利率、新建桔园的最优种植计划、最早获得盈利的年份(以净现值为表征)。该项研究有助于投资者作出正确的投资决策。 展开更多
关键词 GAMS仿真 投资 净现值 回收率 柑桔类果树 美国
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Stroke Rehabilitation In The United States 被引量:2
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作者 Richard D.Zorowitz 周景升 宋为群 《中国康复医学杂志》 CAS CSCD 北大核心 2008年第1期5-7,共3页
I have attempted to present you with many of the ways that in the United States we are addressing the issue of motor deficits in stroke survivors. Many of these techniques show promise. However,there is much work to b... I have attempted to present you with many of the ways that in the United States we are addressing the issue of motor deficits in stroke survivors. Many of these techniques show promise. However,there is much work to be done in order to determine which techniques may be the most effective for cer-tain patients. It is also need to figure out the timing of many of these techniques in order to maximize their benefit. As this last slide shows,stroke survivors need to be "involved with their own rescue." Without their motivation and practice,stroke survivors will never reach their maximal functional capacity. With new techniques and technologies,rehabilitation professionals can provide stroke survivors with the means to intensify their therapies to facilitate functional recovery,reorganize the brain and return them to a fulfilling quality of life. 展开更多
关键词 美国 中风 康复治疗 临床医学 康复效果
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避孕 被引量:2
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作者 Mindy A.Smith Leslie A.Shimp Pharm +1 位作者 梁万年 曹红霞 《中国全科医学》 CAS CSCD 2002年第7期511-514,共4页
关键词 避孕 意外妊娠 生物医学 家庭评价 影响因素
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Influence of Gaps Between Multiple Floating Bodies on Wave Forces 被引量:25
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作者 缪国平 H. Ishida T. Saitoh 《China Ocean Engineering》 SCIE EI 2000年第4期407-422,共16页
The present study aims to give general hints about hydrodynamic interactions for water wave diffraction on a super large floating structure composed of a large number of box-shaped modules with many small gaps in betw... The present study aims to give general hints about hydrodynamic interactions for water wave diffraction on a super large floating structure composed of a large number of box-shaped modules with many small gaps in between. And meanwhile, it also aims to seek for an effective way to take the gap influence into consideration without numerical difficulties existing in conventional methods. An asymptotic matching technique is exploited by virtue of the smallness of gaps. Formal potential solutions are established for the near field around the gap ends and the far field away from gap ends, respectively, and the unknowns in those solutions are uniquely determined by asymptotic matching. The eigen-function expansion method is used for the outer far field and a series of pulsating sources at each gap end is introduced to simulate the gap influence. Strong hydrodynamic interaction is observed and a new resonant phenomenon, the mechanism of which differs absolutely from any known ones, is revealed in the present study. Sharp peak responses for both vertical and horizontal wave-exciting forces on each block are found around some special resonance frequencies, which depend on the draft of the structure and the gap width. The present results are of practical significance to the design of links (connectors) of modules for super large floating structures. And the importance is also closely related to the hydro-elasticity analysis for super large floating structures, in which local loads may be as important as the integrated loads. 展开更多
关键词 super large floating structure wave interaction RESONANCE gap influence
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Post-endoscopic retrograde cholangiopancreatography complications:How can they be avoided? 被引量:21
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作者 Juan J Vila Everson LA Artifon Jose Pinhata Otoch 《World Journal of Gastrointestinal Endoscopy》 CAS 2012年第6期241-246,共6页
Endoscopic retrograde cholangiopancreatography(ERCP) has a significant complication rate which can be lowered by adopting technical variations of proven beneficial effect and prophylactic maneuvers such as pancreatic ... Endoscopic retrograde cholangiopancreatography(ERCP) has a significant complication rate which can be lowered by adopting technical variations of proven beneficial effect and prophylactic maneuvers such as pancreatic stenting during ERCP or periprocedural non-steroidal anti-inflammatory drug administration.However,adoption of these prophylactic maneuvers by endoscopists is not uniform.In this editorial we discuss the beneficial effects of the aforementioned maneuvers. 展开更多
关键词 Acute NECROTIZING Anti-inflammatory Agents CATHETERIZATION CHOLANGIOPANCREATOGRAPHY COMPLICATIONS Endoscopic retrograde NON-STEROIDAL Pancreatitis STENTS
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An evaluation of force-based design vs.direct displacement-based design of jointed precast post-tensioned wall systems 被引量:12
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作者 M. Ataur Rahman Sri Sritharan 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2006年第2期285-296,共12页
The unique features of jointed post-tensioned wall systems, which include minimum structural damage and re-centering capability when subjected to earthquake lateral loads, are the result of using unbonded post-tension... The unique features of jointed post-tensioned wall systems, which include minimum structural damage and re-centering capability when subjected to earthquake lateral loads, are the result of using unbonded post-tensioning to attach the walls to the foundation, along with employing energy dissipating shear connectors between the walls. Using acceptance criteria defined in terms of inter-story drift, residual drift, and floor acceleration, this study presents a multiplelevel performance-based seismic evaluation of two five-story unbonded post-tensioned jointed precast wall systems. The design and analysis of these two wall systems, established as the direct displacement-based and force-based solutions for a prototype building used in the PREcast Seismic Structural Systems (PRESSS) program, were performed at 60% scale so that the analysis model could be validated using the PRESSS test data. Both buildings satisfied the performance criteria at four levels of earthquake motions although the design base shear of the direct displacement-based jointed wall system was 50% of that demanded by the force-based design method. The study also investigated the feasibility of controlling the maximum transient inter-story drift in a jointed wall system by increasing the number of energy dissipating shear connectors between the walls but without significantly affecting its re-centering capability. 展开更多
关键词 CONCRETE PRECAST unbonded post-tensioning WALL building code performance-based evaluation force-baseddesign direct-displacement based design
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Characterization of cytotoxic compound from marine sediment derived actinomycete Streptomyces avidinii strain SU4 被引量:4
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作者 Sudha S Masilamani Selvam M 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第10期770-773,共4页
To investigate the cytotoxic activity of actinomycete isolated from marine sediment. Methods: In the present study the DNA was isolated and the ITS region of 16s rRNA was amplified by polymerase chain reaction, using ... To investigate the cytotoxic activity of actinomycete isolated from marine sediment. Methods: In the present study the DNA was isolated and the ITS region of 16s rRNA was amplified by polymerase chain reaction, using two universal bacterial primers, 1492R (5′-GGTTACCTTGTTAC GACTT-3′) and Eubac27F (5′-AGAGTTTGATCCTGGCTC AG-3′). The amplified products were purified using TIANgel mini purification kit, ligated to MD18-T simple vector (TaKaRa), and transformed into competent cells of Escherichia coli DH5α. 16S rRNA gene fragment was sequenced using forward primer M13F (-47) and reverse primer M13R (-48). Blast search sequence similarity was found against the existing non-redundant nucleotide sequence database thus, identified as Streptomyces sp SU, Streptomyces rubralavandulae strain SU1, Streptomyces cacaoi strain SU2, Streptomyces cavourensis strain SU3, Streptomyces avidinii strain SU4, Streptomyces globisporus strain SU5, Streptomyces variabilis strain SU6, Streptomycescoelicolor strain SU 7. Among the eight identified isolates, one actinomycete Streptomyces avidinii strain SU4 was selected for further study. Results: Crude extract of the actinomycete isolate exhibited IC50 in 64.5 μg against Hep-2 cell line, 250 μg in VERO cell line. This value is very close to the criteria of cytotoxicity activity for the crude extracts, as established by the American National Cancer Institute (NCI) is in IC50 < 30 μg /mL. The GC MS analysis showed that the active principle might be 1,2-benzenedicarboxylic acid, bis(2-methylpropyl) ester (12.17%), isooctyl phthalate (15.29%) with the retention time 15.642 and 21.612, respectively. Conclusions: This study clearly proves that the marine sediment derived actinomycetes with bioactive metabolites can be expected to provide high quality biological material for high throughout biochemical and anticancer screening programs. These results help us to conclude that the potential of using metabolic engineering and post genomic approaches to isolate more bioactive compounds and make their possible commercial application is not far off. 展开更多
关键词 ACTINOMYCETES Cytotoxicity ITS sequencing GC MS STREPTOMYCES avidinii CHARACTERIZATION CYTOTOXIC COMPOUND Extra cellular metabolite
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Editorial statement 被引量:47
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作者 Salvatore Gruttadauria Bruno G Gridelli 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第6期647-647,共1页
In the following four articles, we will provide an overview of the current clinical work in different areas of liver transplantation. For many decades, this transplantation has been the treatment choice for patients ... In the following four articles, we will provide an overview of the current clinical work in different areas of liver transplantation. For many decades, this transplantation has been the treatment choice for patients suffering from chronic and acute liver diseases. 展开更多
关键词 GASTROENTEROLOGY
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Early successes and late failures in the prevention of post endoscopic retrograde cholangiopancreatography 被引量:4
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作者 John G Lieb II Peter V Draganov 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第26期3567-3574,共8页
Acute pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP). The only way to prevent this complication is to avoid an ERCP all together. Because of the risks involved, a... Acute pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP). The only way to prevent this complication is to avoid an ERCP all together. Because of the risks involved, a careful consideration should be given to the indication for ERCP and the potential risk/benefit ratio of the test. Once a decision to perform an ERCP is made, the procedure should be carried out with meticulous care by an experienced endoscopist, and with a minimum of pancreatic duct opacification. Several pharmacologic agents have been tested, but to date the most important method of reducing post ERCP pancreatitis is the placement of pancreatic stent. Pancreatic stents should be placed in all patients at high risk of this complication such as those undergoing pancreatic sphincterotomy, pancreatic duct manipulation and intervention, and patients with suspected sphincter of Oddi dysfunction. Pancreatic stents should be also considered in patients requiring precut sphincterotomy to gain biliary access. 展开更多
关键词 Post endoscopic retrograde cholangiopancre-atography pancreatitits SOMATOSTATIN Gabexate IL-10 Pancreatic stents Aspirating catheter Sphincter of Oddidysfunction
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Lateral load pattern in pushover analysis 被引量:9
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作者 孙景江 Tetsuro Ono +1 位作者 赵衍刚 王威 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2003年第1期99-108,共10页
The seismic capacity curves of three types of buildings including frame,frame-shear wall and shear wall ob- tained by pushover analysis under different lateral load patterns are compared with those from nonlinear time... The seismic capacity curves of three types of buildings including frame,frame-shear wall and shear wall ob- tained by pushover analysis under different lateral load patterns are compared with those from nonlinear time history analy- sis.Based on the numerical results obtained a two-phase load pattern:an inverted triangle(first mode)load pattern until the base shear force reaches β times its maximum value,V_(max)followed by a(x/H)~α form,here β and α being some coeffi- cients depending on the type of the structures considered,is proposed in the paper,which can provide excellent approxima- tion of the seismic capacity curve for low-to-mid-rise shear type buildings.Furthermore,it is shown both the two-phase load pattern proposed and the invariant uniform pattern can be used for low-to-mid-rise shear-bending type and low-rise bending type of buildings.No suitable load patterns have been found for high-rise buildings. 展开更多
关键词 pushover analysis performance-based seismic design lateral load pattern nonlinear time history analysis
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