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Treatment of spinal cord injury with biomaterials and stem cell therapy in non-human primates and humans
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作者 Ana Milena Silva Olaya Fernanda Martins Almeida +1 位作者 Ana Maria Blanco Martinez Suelen Adriani Marques 《Neural Regeneration Research》 SCIE CAS 2025年第2期343-353,共11页
Spinal cord injury results in the loss of sensory,motor,and autonomic functions,which almost always produces permanent physical disability.Thus,in the search for more effective treatments than those already applied fo... Spinal cord injury results in the loss of sensory,motor,and autonomic functions,which almost always produces permanent physical disability.Thus,in the search for more effective treatments than those already applied for years,which are not entirely efficient,researches have been able to demonstrate the potential of biological strategies using biomaterials to tissue manufacturing through bioengineering and stem cell therapy as a neuroregenerative approach,seeking to promote neuronal recovery after spinal cord injury.Each of these strategies has been developed and meticulously evaluated in several animal models with the aim of analyzing the potential of interventions for neuronal repair and,consequently,boosting functional recovery.Although the majority of experimental research has been conducted in rodents,there is increasing recognition of the importance,and need,of evaluating the safety and efficacy of these interventions in non-human primates before moving to clinical trials involving therapies potentially promising in humans.This article is a literature review from databases(PubMed,Science Direct,Elsevier,Scielo,Redalyc,Cochrane,and NCBI)from 10 years ago to date,using keywords(spinal cord injury,cell therapy,non-human primates,humans,and bioengineering in spinal cord injury).From 110 retrieved articles,after two selection rounds based on inclusion and exclusion criteria,21 articles were analyzed.Thus,this review arises from the need to recognize the experimental therapeutic advances applied in non-human primates and even humans,aimed at deepening these strategies and identifying the advantages and influence of the results on extrapolation for clinical applicability in humans. 展开更多
关键词 BIOENGINEERING BIOMATERIALS cell therapy humans non-human primates spinal cord injury stem cell therapy
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Genetically modified non-human primate models for research on neurodegenerative diseases 被引量:2
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作者 Ming-Tian Pan Han Zhang +1 位作者 Xiao-Jiang Li Xiang-Yu Guo 《Zoological Research》 SCIE CSCD 2024年第2期263-274,共12页
Neurodegenerative diseases(NDs)are a group of debilitating neurological disorders that primarily affect elderly populations and include Alzheimer's disease(AD),Parkinson's disease(PD),Huntington's disease(... Neurodegenerative diseases(NDs)are a group of debilitating neurological disorders that primarily affect elderly populations and include Alzheimer's disease(AD),Parkinson's disease(PD),Huntington's disease(HD),and amyotrophic lateral sclerosis(ALS).Currently,there are no therapies available that can delay,stop,or reverse the pathological progression of NDs in clinical settings.As the population ages,NDs are imposing a huge burden on public health systems and affected families.Animal models are important tools for preclinical investigations to understand disease pathogenesis and test potential treatments.While numerous rodent models of NDs have been developed to enhance our understanding of disease mechanisms,the limited success of translating findings from animal models to clinical practice suggests that there is still a need to bridge this translation gap.Old World nonhuman primates(NHPs),such as rhesus,cynomolgus,and vervet monkeys,are phylogenetically,physiologically,biochemically,and behaviorally most relevant to humans.This is particularly evident in the similarity of the structure and function of their central nervous systems,rendering such species uniquely valuable for neuroscience research.Recently,the development of several genetically modified NHP models of NDs has successfully recapitulated key pathologies and revealed novel mechanisms.This review focuses on the efficacy of NHPs in modeling NDs and the novel pathological insights gained,as well as the challenges associated with the generation of such models and the complexities involved in their subsequent analysis. 展开更多
关键词 NEURODEGENERATION non-human primate Macaque monkey Animal model Gene modification
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Optical-neural Stimulation in Non-human Primates:Modulating Brain Function and Behavior
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作者 CHEN Yi-Bing WANG Huan YANG Yan 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2024年第10期2379-2391,共13页
Optical-neural stimulation,which encompasses cutting-edge techniques such as optogenetics and infrared neurostimulation,employs distinct mechanisms to modulate brain function and behavior.These advanced neuromodulatio... Optical-neural stimulation,which encompasses cutting-edge techniques such as optogenetics and infrared neurostimulation,employs distinct mechanisms to modulate brain function and behavior.These advanced neuromodulation techniques offer accurate manipulation of targeted areas,even selectively modulating specific neurons,in the brain.This makes it possible to investigate the cause-and-effect connections between neural activity and behavior,allowing for a better comprehension of the intricate brain dynamics towards complex environments.Non-human primates serve as an essential animal model for investigating these complex functions in brain research,bridging the gap between the basic research and clinical applications.One of the earliest optical studies utilizing optogenetic neuromodulation in monkeys was conducted in 2009.Since then,the optical-neural stimulations have been effectively applied in non-human primates.This review summarises recent research that employed optogenetics or infrared neurostimulation techniques to regulate brain function and behavior in non-human primates.The current state of optical-neural stimulations discussed here demonstrates their efficacy in advancing the understanding of brain systems.Nevertheless,there are still challenges that need to be addressed before they can fully achieve their potential. 展开更多
关键词 optical-neural stimulation OPTOGENETICS infrared neurostimulation non-human primates
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Advances in spinal cord injury:insights from non-human primates
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作者 Gaetan Poulen Florence E.Perrin 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2354-2364,共11页
Spinal cord injury results in significant sensorimotor deficits,currently,there is no curative treatment for the symptoms induced by spinal cord injury.Basic and pre-clinical research on spinal cord injury relies on t... Spinal cord injury results in significant sensorimotor deficits,currently,there is no curative treatment for the symptoms induced by spinal cord injury.Basic and pre-clinical research on spinal cord injury relies on the development and characterization of appropriate animal models.These models should replicate the symptoms observed in human,allowing for the exploration of functional deficits and investigation into various aspects of physiopathology of spinal cord injury.Non-human primates,due to their close phylogenetic association with humans,share more neuroanatomical,genetic,and physiological similarities with humans than rodents.Therefore,the responses to spinal cord injury in nonhuman primates most likely resemble the responses to traumatism in humans.In this review,we will discuss nonhuman primate models of spinal cord injury,focusing on in vivo assessments,including behavioral tests,magnetic resonance imaging,and electrical activity recordings,as well as ex vivo histological analyses.Additionally,we will present therapeutic strategies developed in non-human primates and discuss the unique specificities of non-human primate models of spinal cord injury. 展开更多
关键词 BEHAVIOR cellular analysis non-human primates spinal cord injury tissue analysis
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Role Dynamic Allocation of Human-Robot Cooperation Based on Reinforcement Learning in an Installation of Curtain Wall
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作者 Zhiguang Liu Shilin Wang +2 位作者 Jian Zhao Jianhong Hao Fei Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期473-487,共15页
A real-time adaptive roles allocation method based on reinforcement learning is proposed to improve humanrobot cooperation performance for a curtain wall installation task.This method breaks the traditional idea that ... A real-time adaptive roles allocation method based on reinforcement learning is proposed to improve humanrobot cooperation performance for a curtain wall installation task.This method breaks the traditional idea that the robot is regarded as the follower or only adjusts the leader and the follower in cooperation.In this paper,a self-learning method is proposed which can dynamically adapt and continuously adjust the initiative weight of the robot according to the change of the task.Firstly,the physical human-robot cooperation model,including the role factor is built.Then,a reinforcement learningmodel that can adjust the role factor in real time is established,and a reward and actionmodel is designed.The role factor can be adjusted continuously according to the comprehensive performance of the human-robot interaction force and the robot’s Jerk during the repeated installation.Finally,the roles adjustment rule established above continuously improves the comprehensive performance.Experiments of the dynamic roles allocation and the effect of the performance weighting coefficient on the result have been verified.The results show that the proposed method can realize the role adaptation and achieve the dual optimization goal of reducing the sum of the cooperator force and the robot’s Jerk. 展开更多
关键词 Human-robot cooperation roles allocation reinforcement learning
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Role-play联合翻转课堂教学法对护理实习生新生儿复苏知信行的影响 被引量:1
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作者 丁卉 李眉 +3 位作者 陈静 汪婕 蒋丽军 李霖 《临床医学研究与实践》 2024年第26期195-198,共4页
目的分析角色扮演(Role-play)联合翻转课堂教学法对护理实习生新生儿复苏知信行的影响。方法选取2022年10月1日至2023年8月1日在我院产科及儿科实习的80名本科段护理实习生进行前瞻性研究,将其随机分为试验组(采用Role-play联合翻转课... 目的分析角色扮演(Role-play)联合翻转课堂教学法对护理实习生新生儿复苏知信行的影响。方法选取2022年10月1日至2023年8月1日在我院产科及儿科实习的80名本科段护理实习生进行前瞻性研究,将其随机分为试验组(采用Role-play联合翻转课堂教学法进行新生儿复苏技能培训)和对照组(采用传统临床教学法进行新生儿复苏技能培训),各40名。比较两组的教学效果。结果试验组的理论知识、态度信念得分高于对照组,差异具有统计学意义(P<0.05)。试验组的复苏操作得分高于对照组,差异具有统计学意义(P<0.05)。试验组的灵活应变能力、资源利用能力及沟通协作能力得分均高于对照组,差异具有统计学意义(P<0.05)。试验组的教学满意度高于对照组,差异具有统计学意义(P<0.05)。结论Role-play联合翻转课堂教学法在护理实习生新生儿复苏教学中的效果优于传统临床教学法。 展开更多
关键词 role-play教学法 翻转课堂 护理实习生 新生儿复苏 知信行
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The Influence of Academic Self-Efficacy on Learning Engagement in Online Education in China:The Mediating Role of Effort
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作者 Yan Zhang Zhicui Yao Jian Wang 《Journal of Contemporary Educational Research》 2024年第10期61-68,共8页
The shift towards online intelligent learning has become the norm in education and is now a fundamental part of modern educational activities.However,this new model can influence students’learning behavior and lead t... The shift towards online intelligent learning has become the norm in education and is now a fundamental part of modern educational activities.However,this new model can influence students’learning behavior and lead to changes in their approach to learning.Based on online intelligent learning,we investigated how the academic self-efficacy of nursing students affects their engagement with learning and explored the role of academic attribution as a mediator.Five hundred fifty-three nursing college students from Hebei and Hunan provinces in China participated in the online questionnaire.The results revealed that effort plays a mediating role in the relationship between academic self-efficacy and learning engagement. 展开更多
关键词 Academic self-efficacy Learning engagement Online learning Mediating role EFFORT
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Associations between residence and cognitive function among Chinese older adults: the mediating role of leisure activity
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作者 Xiao-Dong Leng Wen-Ping Zeng Mao-Rui Qian 《Medical Data Mining》 2024年第3期46-52,共7页
Background:Cognitive function is a current research hotspot,residence may be related to differences in cognitive function,and the mediating role of leisure activities are limited in Chinese research.This study used le... Background:Cognitive function is a current research hotspot,residence may be related to differences in cognitive function,and the mediating role of leisure activities are limited in Chinese research.This study used leisure activities as a mediating variable to investigate the mediating role of leisure activity between place of residence(city-town-rural)and cognitive function among Chinese older,this is where the innovation of the article comes in.Methods:Using cross-sectional data from the 2018 Chinese Longitudinal Healthy Longevity Survey,Pearson correlation analyses were employed to examine the relationships among various indicators.Mediation analyses were conducted using the SPSS PROCESS macro program,version 3.5,written by Hayes,to explore the mediating effects of leisure activity between place of residence and cognitive function in older adults.Results:A total of 10955 older adults were included in this study,with a mean age of(84.23±11.57)years.Among them,2739(24.8%)lived in the city,3627(33.1%)in town,and 4615(42.1%)in rural areas;their leisure activity score was(5.34±3.77),and their cognitive function score was(24.69±6.65).Place of residence,leisure activities,and cognitive function were significantly correlated(P<0.01).Using city as a reference,place of residence is negatively associated with cognitive function,and place of residence not only had a direct effect on cognitive function in older adults:town-cognitive function(effect=–0.399;95%confidence interval(CI)=(–0.685,–0.113));rural-cognitive function(effect=–0.42;95%CI=(–0.698,–0.141)).There were also indirect effects on cognitive function through the pathway of leisure activity:town-leisure activity-cognitive function(effect=–0.17;95%CI=(–0.246,–0.1)),rural-leisure activity-cognitive function(effect=–0.199;95%CI=(–0.272,–0.13)).Conclusion:Leisure activities play a partially mediating role between the impact of place of residence and cognitive function in Chinese older adults,and it is vital to pay attention to the impact of place of residence on the cognitive function of older adults in various aspects,and to increase the participation rate of older adults in leisure activities,which is beneficial to the prevention of cognitive decline and the protection of older adult’s physical and mental health. 展开更多
关键词 RESIDENCE leisure activity cognitive function intermediary role older adults
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Study on the Promoting Role of Animating Zhuang Non-Heritage Folktales in the Ethnic Culture Industry
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作者 Danya Liu 《Proceedings of Business and Economic Studies》 2024年第3期65-69,共5页
This study aims to explore the role of animating Zhuang non-heritage folktales in promoting the national culture industry.Using literature research,case studies,and comparative research methods,the positive impacts ar... This study aims to explore the role of animating Zhuang non-heritage folktales in promoting the national culture industry.Using literature research,case studies,and comparative research methods,the positive impacts are analyzed in depth across four dimensions:cultural value inheritance,market demand,dissemination channels,and industrial innovation.The results show that animating Zhuang non-heritage folktales can help inherit national culture,meet market demand,broaden communication channels,and promote industrial innovation.Finally,this paper proposes corresponding policy suggestions and implementation paths to provide references for the sustainable development of the ethnic culture industry. 展开更多
关键词 Zhuang folktales ANIMATION National culture industry Promotion role
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Theoretical Analysis and Practical Reflection on the Role Conflict of Double-Qualified Teachers in University-Affiliated Hospitals
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作者 Yuanyuan Jia Yu Cai +2 位作者 Siqi Wang Ying Yang Ge Wu 《Journal of Contemporary Educational Research》 2024年第5期27-36,共10页
Taking role conflict as the starting point,this article examines and reflects on the development of clinical teachers.In the process of the occurrence,development,and resolution of role conflicts among clinical teache... Taking role conflict as the starting point,this article examines and reflects on the development of clinical teachers.In the process of the occurrence,development,and resolution of role conflicts among clinical teachers,there are many hidden issues related to the development of clinical teachers.The development of clinical teacher teaching and role conflict management contain similar educational philosophies and practical issues.This study draws on classic theories and research achievements in the development of university teachers and conducts theoretical analysis and practical reflection on the development of clinical teachers in medical colleges from the perspective of role conflict in social psychology.Policy recommendations are proposed,including strengthening the construction of teaching systems at the hospital organizational environment level,enhancing the role identity and teacher beliefs of clinical teachers,promoting their teaching development and academic learning,and ensuring their normal teaching investment;promoting leadership support at the level of interpersonal interaction and leveraging the role of colleague support in alleviating role conflicts;enhancing individual teacher beliefs,teacher role learning,and role skills. 展开更多
关键词 University-affiliated hospitals Double-qualified teachers role conflict
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Exploration of the Evolution of Teacher Roles and Professional Development Needs Among University English Instructors
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作者 Yuanyuan Zhou 《Journal of Contemporary Educational Research》 2024年第5期207-211,共5页
The role of university English instructors has evolved significantly over the years,encompassing various aspects.This paper explores the evolution of the role of university English instructors and examines the current... The role of university English instructors has evolved significantly over the years,encompassing various aspects.This paper explores the evolution of the role of university English instructors and examines the current challenges and opportunities they face in today’s educational landscape.It delves into the multifaceted nature of their responsibilities and discusses the importance of continuous professional development to meet the evolving needs of students and the demands of the profession. 展开更多
关键词 Teacher roles Professional development University English instructors
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Exploration of Teaching Development Strategies for Double-Qualified Teachers in University- Affiliated Hospitals Based on Role Conflict Theory
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作者 Yuanyuan Jia Yu Cai +2 位作者 Siqi Wang Ying Yang Ge Wu 《Journal of Contemporary Educational Research》 2024年第6期121-127,共7页
This study draws on the classic theories and research achievements of university teacher development,and from the perspective of role conflict in social psychology,proposes policy recommendations for the development o... This study draws on the classic theories and research achievements of university teacher development,and from the perspective of role conflict in social psychology,proposes policy recommendations for the development of clinical teachers in medical colleges,including following different stages of teacher development and designing teaching development strategies at different levels;designing the content and form of teaching development activities to meet the temporal and spatial needs of clinical teachers;and building an academic community for clinical teachers to promote the creation of teaching development behaviors. 展开更多
关键词 University-affiliated hospitals Double-qualified teachers role conflict theory Teaching development strategies
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Mediating role of fear of progression between sensory processing sensitivity and stigma in lung cancer patients:a cross-sectional study
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作者 Nan Shen Jiao Yang +5 位作者 Qian-Rong Yang Ruo-Jia Wu Jing Yang Kai-Wen Dong Yan-Qiu Zhao Xiu-Mei Yang 《Frontiers of Nursing》 2024年第4期373-378,共6页
Objective:To explore the association of sensory processing sensitivity(SPS)and stigma as well as the mediating role of fear of progression(FoP)in lung cancer patients.Methods:Two hundred and forty-two lung cancer pati... Objective:To explore the association of sensory processing sensitivity(SPS)and stigma as well as the mediating role of fear of progression(FoP)in lung cancer patients.Methods:Two hundred and forty-two lung cancer patients completed a self-reported questionnaire,which included the highly sensitive person scale(HSPS),fear of progression questionnaire-short form(FoP-Q-SF),and the Cataldo Lung Cancer Stigma Scale(CLCSS).Results:CLCSS was positively correlated with FoP(Pearson correlation=0.217,P<0.01)and HSPS(Pearson correlation=0.187,P<0.01),FoP was positively correlated with HSPS(Pearson correlation=0.199,P<0.01).FoP played a mediating role between SPS and stigma(a×b=0.025,95%confidence intervals[CI][0.004,0.054]),and the proportion of mediating effect(ab/c)was 21%(ab=0.025,c=0.120).Conclusions:Patients with higher SPS reported higher level of stigma,and FoP has a mediating role between SPS and stigma.Our discussion deemed that psychological intervention may help higher SPS patients reduce the harm of FoP and further reduce stigma. 展开更多
关键词 fear of progression lung cancer mediating role sensory processing sensitivity STIGMA
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Women’s Social Roles and Peace Building in Al-Abassiya Locality:2012-2024
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作者 Abida Adam Altayeeb Mohammed Afag Mohamed Sadig Hazel Barrett 《Sociology Study》 2024年第5期236-247,共12页
This research focused on the social roles of women in Al-Abassiya locality,South Kordofan State,examining the obstacles they face and the impact on their participation in peace building.Using qualitative methods,data ... This research focused on the social roles of women in Al-Abassiya locality,South Kordofan State,examining the obstacles they face and the impact on their participation in peace building.Using qualitative methods,data were collected through various means,revealing that conflicts have significantly affected women’s lives,particularly in rural areas.Women play key roles in family,education,health services,and humanitarian aid,but their involvement in conflict resolution and peace building activities is limited.Obstacles include cognitive,economic,social,and institutional barriers.Recommendations include providing education and training programs,strengthening economic status,ensuring women’s representation in decision-making bodies,advocating for legal reforms promoting gender equality,improving access to information technologies,educating communities on women’s involvement in peace building,and providing support services for women affected by conflicts. 展开更多
关键词 WOMEN Al-Abassiya locality social roles peace building conflicts rural areas education gender equality DECISION-MAKING support services
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The Role of Teachers’Apperception in Herbart’s Theory for Chinese Teaching in Shenzhen Primary Schools of China
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作者 Huangzhong Luo Detkul Matavanukul Ed.D 《Journal of Contemporary Educational Research》 2024年第11期347-354,共8页
This paper deeply analyzes the practical application of Herbart’s educational concept in contemporary education and teaching,especially its guiding significance to the primary school Chinese classroom in Shenzhen are... This paper deeply analyzes the practical application of Herbart’s educational concept in contemporary education and teaching,especially its guiding significance to the primary school Chinese classroom in Shenzhen area.Herbart proposed that teachers should play a key role in students’cognitive process,that is,help students better understand and master new knowledge by combining it with existing knowledge.The survey results show that although teachers have some understanding of Herbart’s educational philosophy,it is not widely used in the concrete teaching process.However,the study also shows that there is a positive relationship between Herbart’s theory and students’academic performance,indicating that it plays an important role in improving students’interest and engagement in learning.The research also reveals the differences between educational concepts and practices,as well as the uneven distribution of educational resources,and puts forward measures to alleviate these contradictions,such as strengthening teacher training,improving teaching methods,and emphasizing moral education.At the same time,the study also highlights the critical role of teachers in promoting knowledge integration,arousing learning enthusiasm,shaping students’moral character,and promoting personal and professional growth. 展开更多
关键词 Herbart’s educational theory Teacher apperception role Teaching method optimization Educational resource allocation
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Cloning of a MADS Box Gene(GhMADS3)from Cotton and Analysis of Its Homeotic Role in Transgenic Tobacco 被引量:8
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作者 郭余龙 祝钦泷 +1 位作者 郑尚永 李名扬 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第6期527-535,共9页
A MADS box gene (GhMADS3) was cloned from cotton (Gossypium hirsutum L.) based on EST sequences. The predicted protein sequence of GhMADS3 showed 85%, 73%, and 62% identity with Theobroma cacao TcAG, Antirrhinum m... A MADS box gene (GhMADS3) was cloned from cotton (Gossypium hirsutum L.) based on EST sequences. The predicted protein sequence of GhMADS3 showed 85%, 73%, and 62% identity with Theobroma cacao TcAG, Antirrhinum majus FAR, and Arabidopsis thaliana AG, respectively, and was grouped with AG homologues when the full length sequences excluding N-extensions were compared. GhMADS3 expressed in the wild type cotton flower primarily in stamens and carpels, which was comparable to AG in Arabidopsis. However, it was not expressed in floral buds of a homeotic cotton variant chvl. Ectopic expression of GhMADS3 in tobacco (Nicotiana tabacum L.) resulted in flowers with sepal-to-carpel and petal-to-stamen transformation. The carpelloid first whorl organs, with stigmatic tissue on their upper edges, had a white appearance when compared with the dark green color of the wild type sepals. At times, long filaments were observed at the fusion site of the first carpelloid oranges. The second whorl organs in staminoid were usually smaller than the wild type and the color was changed from pink to white. These results suggest that GhMADS3 has a homeotic role in flower development. 展开更多
关键词 MADS-BOX AG subfamily homeotic role COTTON flower development
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Progress of non-human primate animal models of cancers 被引量:8
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作者 夏厚军 陈策实 《Zoological Research》 CAS CSCD 北大核心 2011年第1期70-80,共11页
Cancer is the second leading disease causing human death.Pre-clinical in vivo studies are essential for translating in vitro laboratory research results into the clinic.Rodents,including the mouse and rat,have been wi... Cancer is the second leading disease causing human death.Pre-clinical in vivo studies are essential for translating in vitro laboratory research results into the clinic.Rodents,including the mouse and rat,have been widely used for pre-clinical studies due to their small size,clear genetic backgrounds,rapid propagation,and mature transgenic technologies.However,because rodents are evolutionarily distinct from humans,many pre-clinical research results using rodent models cannot be reproduced in the clinic.Non-human primates(NHPs) may be better animal models than rodents for human cancer research because NHPs and humans share greater similarity in regards to their genetic evolution,immune system,physiology and metabolism.This article reviews the latest progress of cancer research in NHPs by focusing on the carcinogenesis of different NHPs induced by chemical and biological carcinogens.Finally,future research directions for the use of NHPs in cancer research are discussed. 展开更多
关键词 non-human primate CANCER Tree shrew
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Semantic role labeling based on conditional random fields 被引量:9
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作者 于江德 樊孝忠 +1 位作者 庞文博 余正涛 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期361-364,共4页
Due to the fact that semantic role labeling (SRL) is very necessary for deep natural language processing, a method based on conditional random fields (CRFs) is proposed for the SRL task. This method takes shallow ... Due to the fact that semantic role labeling (SRL) is very necessary for deep natural language processing, a method based on conditional random fields (CRFs) is proposed for the SRL task. This method takes shallow syntactic parsing as the foundation, phrases or named entities as the labeled units, and the CRFs model is trained to label the predicates' semantic roles in a sentence. The key of the method is parameter estimation and feature selection for the CRFs model. The L-BFGS algorithm was employed for parameter estimation, and three category features: features based on sentence constituents, features based on predicate, and predicate-constituent features as a set of features for the model were selected. Evaluation on the datasets of CoNLL-2005 SRL shared task shows that the method can obtain better performance than the maximum entropy model, and can achieve 80. 43 % precision and 63. 55 % recall for semantic role labeling. 展开更多
关键词 semantic role labeling conditional random fields parameter estimation feature selection
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A New Role Hierarchy Model for Role Based Access Control 被引量:2
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作者 吕宜洪 宋瀚涛 龚元明 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期409-413,共5页
A new role hierarchy model for RBAC (role-based access control) is presented and its features are illustrated through examples. Some new concepts such as private permission, public permission and special permission ar... A new role hierarchy model for RBAC (role-based access control) is presented and its features are illustrated through examples. Some new concepts such as private permission, public permission and special permission are introduced, based on the RRA97 model. Some new role-role inheriting forms such as normal inheritance, private inheritance, public inheritance and special-without inheritance are defined. Based on the ideas mentioned, the new role hierarchy model is formulated. It is easier and more comprehensible to describe role-role relationships through the new model than through the traditional ones. The new model is closer to the real world and its mechanism is more powerful. Particularly it is more suitable when used in large-scale role hierarchies. 展开更多
关键词 RBAC access control role INHERIT role hierarchy
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Role-Based Modeling in Enterprise Dynamic Alliance 被引量:1
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作者 何文奇 李刚 +1 位作者 唐春华 王茜 《Journal of Southeast University(English Edition)》 EI CAS 2000年第2期58-65,共8页
In enterprise dynamic alliance towards agile manufacturing systems, any group needs to know which activities it must take part in, in what order those activities take place and how many other groups it must interact ... In enterprise dynamic alliance towards agile manufacturing systems, any group needs to know which activities it must take part in, in what order those activities take place and how many other groups it must interact with. The traditional procedural models can’t meet the requirement of the modeling for an enterprise dynamic alliance. In this paper, we use role based models for an enterprise modeling. Role based models group activities into roles, which describe the desired behavior of individual enterprise. We have developed a graphical modeling tool built on Web/DCOM platform according to Petri net theory and role based methodology. 展开更多
关键词 Petri net flow manager process manager role
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