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Limiting Factors and Countermeasures for the Development of Biological Herbicides
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作者 Yanqi YANG 《Plant Diseases and Pests》 CAS 2023年第2期8-13,共6页
This paper mainly analyzes the main limiting factors in the development of biological herbicides,such as narrow herbicidal spectrum,vulnerable to environmental impacts,difficulties in preparing dosage forms,difficult ... This paper mainly analyzes the main limiting factors in the development of biological herbicides,such as narrow herbicidal spectrum,vulnerable to environmental impacts,difficulties in preparing dosage forms,difficult separation and low yield of active substances,biological safety,etc.Moreover,countermeasures and suggestions are put forward,including strengthening the study of biological screening of herbicidal activity,microbial metabolites and their use as lead compounds,dosage forms,fungi complex formulation,fungi and herbicide complex formulation,and fermentation technology. 展开更多
关键词 Biological herbicide Limiting factor COUNTERMEASURE
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Analysis on the Influencing Factors of Low-carbon Economy and Its Mitigation Countermeasures in Sichuan Province 被引量:3
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作者 FU Miao-miao,YAO Jian College of Architecture and Environment,Sichuan University,Chengdu 610065,China 《Meteorological and Environmental Research》 CAS 2011年第11期49-52,71,共5页
[Objective]The study aimed to analyze the influencing factors of low-carbon economy and its mitigation countermeasures in Sichuan Province.[Method]Taking Sichuan Province as an example,an extended STIRPAT model was es... [Objective]The study aimed to analyze the influencing factors of low-carbon economy and its mitigation countermeasures in Sichuan Province.[Method]Taking Sichuan Province as an example,an extended STIRPAT model was established firstly,then the impacts of population,economy and technology on carbon emissions from 2000 to 2009 were analyzed econometrically by using the principal component analysis method.Finally,some corresponding countermeasures to reduce carbon dioxide emissions were put forward.[Result]At present,population scale had the greatest influence on carbon emissions in Sichuan Province,then energy consumption per industrial added value and the proportion of industrial added value to GDP.In addition,the influence of population scale on carbon emissions was still greater than that of population structure,and technical factor also has certain explanatory power on carbon emissions.Some countermeasures,like controlling population growth,advocating low-carbon life style and consumption model,paying more attention to the strategic adjustment of industrial structure to gradually reduce the proportion of high-carbon industries,encouraging energy consumption and emissions reduction plus scientific and technological innovation in a new energy technology filed,could be adopted to reduce carbon dioxide emissions,so as to adjust to the development of low-carbon economy in Sichuan Province.[Conclusion]The research could provide references for the establishment of policies for reducing carbon emissions. 展开更多
关键词 Sichuan Province Low-carbon economy Influencing factors Mitigation countermeasures STIRPAT model Principal component analysis China
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A Review of Causes,Influencing Factors and Countermeasures of Haze Pollution in China 被引量:1
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作者 Chuai Xiaoming Wang Jiajia +3 位作者 Zhou Haixia Fan Chao Han Yanjun Gao Jun 《Meteorological and Environmental Research》 CAS 2019年第3期25-28,共4页
Haze pollution is a hot research topic at present,and it is of great significance to prevent and control haze pollution.In this paper,specific causes of haze pollution in China are analyzed by literature research and ... Haze pollution is a hot research topic at present,and it is of great significance to prevent and control haze pollution.In this paper,specific causes of haze pollution in China are analyzed by literature research and summary,and impacts of economic structure,energy structure and compound factors on haze pollution are explored.Finally,the prevention and control measures of haze pollution are summarized. 展开更多
关键词 HAZE POLLUTION CAUSE Impact factor COUNTERMEASURE
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Study on the Current Situation and Protection Countermeasures of Wild Plant Resources in Xishuangbanna National Nature Reserve 被引量:3
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作者 YANG Zhong-xing1, YIN Wu-yuan2, AI Jian-lin1 1. Yunnan Forestry Inventory and Planning Institute, Kunming 650051, China 2. Southwest Forestry University, Kunming 650224, China 《Meteorological and Environmental Research》 CAS 2011年第4期79-82,共4页
[Objective] The aim was to study the current situation and protection countermeasures of wild plant resources in Xishuangbanna National Nature Reserve. [Method] The current situation of wild plant resources in Xishuan... [Objective] The aim was to study the current situation and protection countermeasures of wild plant resources in Xishuangbanna National Nature Reserve. [Method] The current situation of wild plant resources in Xishuangbanna National Nature Reserve was researched by means of route survey, sample plot survey and literature survey, and then the main impact factors of wild plant resources were analyzed by using participatory rural appraisal and problem tree analysis, finally protection countermeasures were put forward according to current situation and main impact factors. [Result] There were 2 779 species of vascular plants belonging to 214 families and 1 012 genera (including subfamilies and varieties) in Xishuangbanna National Nature Reserve, among them, there existed 261 species of pteridophyte belonging to 41 families and 91 genera, 14 species of gymnosperm belonging to 6 families and 6 genera, and 2 504 species of angiosperm belonging to 167 families and 915 genera. Wild plant resources in reserve were mainly affected by planting under forest, habitat fragmentation, cutting trees, collection and utilization of no-timber products, development of animal husbandry, insufficient recognition of community residents to reserve management establishment and lots of floating population. In the future, wild plant resources in reserve could be protected through strengthening propaganda, education and management, enforcing the law strictly and other countermeasures. [Conclusion] The study could provide theoretical foundation for the protection of wild plant resources in Xishuangbanna National Nature Reserve. 展开更多
关键词 Wild plant resources Protection countermeasures Impact factors National Nature Reserve XISHUANGBANNA China
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The Research on Countermeasures of Green Agricultural Development in Jiangsu Province 被引量:3
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作者 DU Hua-zhang Jiangyan Municipal Bureau of Agriculture,Jiangyan 225500,China 《Asian Agricultural Research》 2010年第3期31-37,共7页
Firstly,the thesis introduces the connotation of green agriculture,indicating that the green agriculture has 4 characteristics,namely openness,continuity,high efficiency and standardization,compared with the tradition... Firstly,the thesis introduces the connotation of green agriculture,indicating that the green agriculture has 4 characteristics,namely openness,continuity,high efficiency and standardization,compared with the traditional agricultural development model.Secondly,the advantages of developing green agriculture in Jiangsu Province are discussed,namely rich agricultural resources,notable technological advantage,solid agricultural foundation,high quality of agricultural products,great market prospect of green consumption,and notable policy advantage.In view of the increasing shortage of natural resources,increasing restriction of rural labor force,increasing deterioration of rural environment,inadequate popularization of green agriculture,and fierce competition at home and abroad,the restricted factors of developing green agriculture in Jiangsu Province are introduced.Finally,in view of the agricultural concept innovation,green agricultural system innovation,agricultural technology innovation,agricultural management innovation,operation system innovation,ecological system innovation,development of tourism agriculture and regional differentiation development strategy,the relevant countermeasures and suggestions are put forward,in order to explore a new agricultural development model for Jiangsu's modern agricultural development. 展开更多
关键词 Green AGRICULTURE Advantages RESTRICTED factors DE
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Causes and Control Countermeasures of Haze in Beijing-Tianjin - Hebei Region 被引量:1
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作者 Li Yunyan Wang Lihua +2 位作者 Wang Jing Ma Jingyu Wang Huimei 《Meteorological and Environmental Research》 CAS 2017年第5期43-48,共6页
Firstly,time and space characteristics of haze in Beijing-Tianjin-Hebei( B-T-H) region are revealed; results of haze source apportionment in the area are analyzed. Secondly,the influencing factors of haze are explored... Firstly,time and space characteristics of haze in Beijing-Tianjin-Hebei( B-T-H) region are revealed; results of haze source apportionment in the area are analyzed. Secondly,the influencing factors of haze are explored from the aspects of economic development,energy structure,industrial structure,transportation,etc. The internal driving forces of haze are also researched based on the DPSIR model. Finally some feasible and comprehensive control countermeasures against haze are suggested. 展开更多
关键词 Characteristics of HAZE Influencing factors Driving FORCES GOVERNANCE countermeasures
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Analysis on Function Orientation and Development Countermeasures of New Agricultural Business Entities 被引量:1
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作者 Wang Yang Wang Yan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第2期82-88,共7页
Along with the rapid advance of industrialization and urbanization process, fostering new agricultural business entities become inevitable for agricultural transformation and the construction of agricultural moderniza... Along with the rapid advance of industrialization and urbanization process, fostering new agricultural business entities become inevitable for agricultural transformation and the construction of agricultural modernization in China. The status of the new agricultural business entities determines the level of modern agricultural development. In recent years, new agricultural business entities have grew rapidly. However, there are still many problems including the difficulties in financing loans, inadequate agricultural insurance system, bad implementation of agricultural subsidies, jagged agricultural talents and so on. In order to foster new agricultural business entities, countermeasures should be carried out to ensure financial support, perfect the agricultural insurance, strengthen the level of agricultural subsidies, strive to develop the degree of specialization agricultural operators and so on. 展开更多
关键词 new type agricultural business entities restrictive factor function orientation
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Restrictions and Countermeasures of Rural Vocational Education in Urban-rural Integration 被引量:3
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作者 LIU Jian-ling Zhangjiakou Party College of CPC,Zhangjiakou 075000,China 《Asian Agricultural Research》 2012年第5期79-82,共4页
Developing rural vocational education is of great significance to urban-rural integration: developing rural vocational education is helpful to cultivating new farmers for construction of new socialist countryside,favo... Developing rural vocational education is of great significance to urban-rural integration: developing rural vocational education is helpful to cultivating new farmers for construction of new socialist countryside,favorable to improving farmers' ability of finding jobs and starting undertaking, and beneficial to transfer of rural surplus labor and acceleration of urbanization. Restrictions on development rural vocational education mainly include: low value cognition of society and social assessment of rural vocational education; out of balance of cost and expected return of rural vocational education; the quality of supply of rural vocational education failure to satisfy demand of socio-economic development; imperfect rural vocational education system. In view of these,following countermeasures and suggestions are put forward: strengthen propaganda and guidance to build environment of public opinion for rural vocational education; push forward rural vocational compulsory education system to lay social foundation for rural vocational education; reinforce policy support to assist in building rural vocational education system; improve education system to build overall framework of rural vocational education; perfect laws and regulations to establish system and norm for development of rural vocational education. 展开更多
关键词 Urban-rural INTEGRATION RURAL VOCATIONAL EDUCATION
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Research on Water-Filling Patterns and Countermeasures──A case study of Xiaotun Coal Mine
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作者 董东林 武强 +7 位作者 孙桂敏 钱增江 陈萍 陈佩佩 邹德禹 刘金韬 袁建明 Hannie de Ruiter 《International Journal of Mining Science and Technology》 SCIE EI 2000年第1期45-48,共4页
There are many water-filling factors in Xiaotun Coal Mine, such as effective precipitation, goaf water, mining-induced fissure zone, surface water system, aquifers and tectonics. For different mining levels, the relat... There are many water-filling factors in Xiaotun Coal Mine, such as effective precipitation, goaf water, mining-induced fissure zone, surface water system, aquifers and tectonics. For different mining levels, the relative importance of these factors is different, and the water-filling condition is changed accordingly. So it is urgent to make it clear for mining. To ensure the safety of mining, we build a system of preventing mine water-filling using detailed AHP (analytical hierarchy process) calculation. This system is based on the analysis of mine water-filling factors in order to define the relative importance of the factors. Decision-makers use it as a strong scientific basis for Xiaotun Coal Mine.The method offered in this paper has been proved to be very applicable. 展开更多
关键词 WATER-FILLING pattern WATER-FILLING factor AHP method RESEARCH of COUNTERMEASURE
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Quantification and control of restrictive ecological factors in acidogenic de-sulfate bioreactor 被引量:1
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作者 王爱杰 任南琪 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第1期32-37,共6页
As an artificial microbial ecosystem, acidogenic de sulfate bioreactor has high efficiency of sulfate removal. The restrictive ecological factors, including causing ecological factors, such as COD/SO 4 2- ratio and su... As an artificial microbial ecosystem, acidogenic de sulfate bioreactor has high efficiency of sulfate removal. The restrictive ecological factors, including causing ecological factors, such as COD/SO 4 2- ratio and sulfate loading rate (Ns), and following ecological factors, such as pH value, oxidation reduction potential (ORP) and alkalinity (ALK) have significant effect on the ability and stability of acidogenic de sulfate bio reactor. Continuous flow and batch test were carried out to investigate the quantification and control of COD/SO 4 2- ratio, Ns, pH value, ORP and ALK in acidogenic de sulfate bioreactor supplied with molasses wastewater as sole organic carbon source and sodium sulfate as electron donor. It was demonstrated that In order to maintain high sulfate removal rate (SRR) of 80% to 90%, the restrictive factors should meet all the requirement as follows: k COD/ SO 4 2-  ratio≥2.0, Ns≤7.5 kg (m 3·d) -1 ,pH=5.7~6.2,ORP=-320~-420 mV and  ALK= 1 500~2 000 mg/L. 展开更多
关键词 acidogenic DE SULFATE bio reactor restrictive ECOLOGICAL factors quantification control WASTEWATER treatment
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Model identification with BPNN on restrictive ecological factors of SRB for sulfate-reduction 被引量:1
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作者 王爱杰 任南琪 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第2期125-128,共4页
The model of back-propagation neural network (BPNN) was presented to demonstrate the effect of restrictive ecological factors, COD/SO 4 2- ratio, pH value, alkalinity (ALK) and SO 4 2- loading rate (Ns), on sulfat... The model of back-propagation neural network (BPNN) was presented to demonstrate the effect of restrictive ecological factors, COD/SO 4 2- ratio, pH value, alkalinity (ALK) and SO 4 2- loading rate (Ns), on sulfate reduction of Sulfate Reducing Bacteria (SRB) in an acidogenic sulfate reducing reactor supplied with molasses as sole organic carbon source and sodium sulfate as electron acceptor. The compare of experimental results and computer simulation was also discussed. It was shown that the method of BPNN had a powerful ability to analyze the ecological characteristic of acidogenic sulfate reducing ecosystem quantitatively. 展开更多
关键词 sulfate-reducing bacteria(SRB) restrictive ECOLOGICAL factors BACK-PROPAGATION neural network (BPNN) model identification
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开放大学发展社区教育制约因素与对策研究 被引量:2
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作者 金炳顺 张金明 朱艳红 《辽宁高职学报》 2024年第2期92-94,99,共4页
针对地方开放大学发展社区教育面临思想认识不到位、办学体系不健全、运作模式滞后、办学经费匮乏和师资队伍不足等问题及制约因素,从提高政治站位、创新办学理念、实现社区教育和老年教育融合发展等方面提出发展社区教育的对策与建议,... 针对地方开放大学发展社区教育面临思想认识不到位、办学体系不健全、运作模式滞后、办学经费匮乏和师资队伍不足等问题及制约因素,从提高政治站位、创新办学理念、实现社区教育和老年教育融合发展等方面提出发展社区教育的对策与建议,为办好社区教育、推进学习型社会做出新贡献。 展开更多
关键词 开放大学 社区教育制约因素 对策
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Examining the Impact Factors and Strategies to Mitigate Economic Fluctuation in the Real Estate Sector
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作者 Yadong Xiao 《Proceedings of Business and Economic Studies》 2023年第5期54-58,共5页
With the continuous growth of the economy and the rapid pace of urbanization,the real estate sector has assumed an increasingly substantial role within the national economy.Ensuring the stable and sustainable developm... With the continuous growth of the economy and the rapid pace of urbanization,the real estate sector has assumed an increasingly substantial role within the national economy.Ensuring the stable and sustainable development of the real estate sector to maximize its societal and economic contributions has become a pressing issue.China,presently engaged in an extensive urbanization drive,places real estate development and sales as pivotal components in the broader real estate industry,significantly impacting the overall functionality of the real estate market.Real estate,being a comprehensive system encompassing land,housing,infrastructure,and other key elements,exerts a profound influence on people’s basic needs such as shelter,sustenance,and daily living.Its evolution directly shapes the trajectory of the national economy and social stability.Therefore,to foster the consistent and robust growth of China’s real estate economy,it is necessary to implement effective measures that entail a systematic and thorough analysis of the factors responsible for the fluctuations in China’s real estate economy. 展开更多
关键词 Real estate Economic fluctuations Influencing factors countermeasures
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陆军飞行人员心理应激障碍的影响因素及应对措施概述 被引量:1
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作者 王永堂 杨策 《陆军军医大学学报》 CAS CSCD 北大核心 2024年第1期27-32,共6页
陆军航空兵是陆军编制序列中的现代高技术兵种,具有灵活机动、快速打击的优点。陆军飞行人员在长时间执飞任务中面临低压、缺氧、噪声、振动等恶劣环境以及各种军事应激,承受着比普通人群更大的身心压力,更易发生心理应激障碍,严重影响... 陆军航空兵是陆军编制序列中的现代高技术兵种,具有灵活机动、快速打击的优点。陆军飞行人员在长时间执飞任务中面临低压、缺氧、噪声、振动等恶劣环境以及各种军事应激,承受着比普通人群更大的身心压力,更易发生心理应激障碍,严重影响战斗力。在执飞过程中面临的特殊外界环境会导致陆军飞行人员出现情绪不稳定,空中不适应,以及紧张、焦虑、抑郁等一系列心理应激障碍。科学优化心理选拔、培训标准,加强心理耐受训练,定期进行心理咨询、干预和疏导,尤其注重平时精神健康的检测与评估等措施可有效促进陆军飞行人员心理健康,预防心理应激障碍的发生。明确陆军飞行人员心理应激障碍的影响因素及应对措施,对提高陆军航空兵部队作业能力及战斗力具有重要意义。 展开更多
关键词 陆军飞行人员 心理应激障碍 军事医学 军事心理学
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内蒙古筑牢我国北方重要生态安全屏障的现实基础、制约因素与机制构建 被引量:1
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作者 董佳宇 《内蒙古社会科学》 CSSCI 北大核心 2024年第2期206-212,共7页
筑牢我国北方重要生态安全屏障是内蒙古肩负的重大责任。从建设历程看,内蒙古筑牢生态安全屏障经历了反复调试、稳健推进和释放能量的演进历程。从建设成效看,以林草修复为基础的生态环境改善效果显著,制度体系保障机制逐渐完善,多维度... 筑牢我国北方重要生态安全屏障是内蒙古肩负的重大责任。从建设历程看,内蒙古筑牢生态安全屏障经历了反复调试、稳健推进和释放能量的演进历程。从建设成效看,以林草修复为基础的生态环境改善效果显著,制度体系保障机制逐渐完善,多维度治理创新和数智技术运用初见成效,产业和能源结构日趋升级。但生态理性缺失、生态要素结构失衡、传统产业绿色化转型缓慢、环保大数据共享不足等仍制约着生态安全屏障建设。因此,要树立大生态观,以多维度协同治理模式为先导、以治理主体耦合运行机制为主线、以生产生活绿色化为载体、以遵循自然规律的生态技术为驱动、以代内与代际并重的监管机制为补充是筑牢我国北方重要生态安全屏障的践行之路。 展开更多
关键词 筑牢生态安全屏障 现实基础 制约因素 机制 内蒙古
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江苏高效节水灌溉发展现状及对策研究 被引量:1
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作者 孙浩 杨笑 刘晓璇 《中国水利》 2024年第1期52-54,共3页
发展高效节水灌溉是江苏现代农业发展的必由之路。总结了江苏高效节水灌溉现状,分析发展高效节水灌溉的潜力和需求,从自然条件、技术装备、投入保障、管护水平等角度剖析发展的制约因素,提出选择适宜发展模式、强化科技支撑、加强典型... 发展高效节水灌溉是江苏现代农业发展的必由之路。总结了江苏高效节水灌溉现状,分析发展高效节水灌溉的潜力和需求,从自然条件、技术装备、投入保障、管护水平等角度剖析发展的制约因素,提出选择适宜发展模式、强化科技支撑、加强典型示范引领、注重宣传发动等对策措施。 展开更多
关键词 高效节水灌溉 发展潜力 制约因素 对策
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胎儿生长受限患者胎盘组织中VEGFA、HIF-1α表达及临床意义
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作者 王宏艳 徐志文 +2 位作者 孙晓东 朱秀民 崔元日 《中国计划生育学杂志》 2024年第7期1663-1667,1672,共6页
目的:探究胎儿生长受限(FGR)患者胎盘组织中血管内皮生长因子A(VEGFA)、缺氧诱导因子(HIF)-1α表达及临床意义。方法:选择2020年5月-2022年9月在本院确诊FGR并住院分娩的孕妇116例(FGR组)、分娩正常孕妇(新生儿正常)116例为对照组临床... 目的:探究胎儿生长受限(FGR)患者胎盘组织中血管内皮生长因子A(VEGFA)、缺氧诱导因子(HIF)-1α表达及临床意义。方法:选择2020年5月-2022年9月在本院确诊FGR并住院分娩的孕妇116例(FGR组)、分娩正常孕妇(新生儿正常)116例为对照组临床资料。qRT-PCR检测胎盘组织中VEGFA、HIF-1α的mRNA表达情况,免疫组化法检测VEGFA、HIF-1α的蛋白表达情况。Pearson相关性分析VEGFA与HIF-1α的相关性以及与FGR患者临床资料相关性;多因素logistic回归分析影响FGR发生的因素。结果:FGR组VEGFA蛋白阳性表达率(25.9%)低于对照组(64.7%),HIF-1α蛋白阳性表达率(67.2%)高于对照组(24.1%);FGR组胎盘组织中VEGFA mRNA表达水平(0.75±0.20)低于对照组(1.00±0.23),HIF-1α mRNA表达水平(1.26±0.25)高于对照组(1.01±0.19)(均P<0.05)。FGR患者胎盘组织中VEGFA mRNA与HIF-1α mRNA呈负相关(P<0.05)。FGR患者新生儿出生1 min Apgar评分、胎盘重量、胎盘体积、新生儿体重与VEGFA表达水平呈正相关,与HIF-1α表达水平呈负相关;HIF-1α升高为影响FGR发生的危险因素,VEGFA升高为保护因素(均P<0.05)。结论:FGR患者胎盘组织中VEGFA低表达、HIF-1α高表达,二者影响FGR的发生及新生儿出生质量。 展开更多
关键词 胎儿生长受限 胎盘组织 血管内皮生长因子A 缺氧诱导因子-1Α 相关性 影响因素 新生儿
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三维能量多普勒超声参数联合胎盘生长因子对早发型胎儿生长受限的预测价值
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作者 李娟娟 林雁 王卫平 《实用临床医药杂志》 CAS 2024年第10期13-16,23,共5页
目的探讨三维能量多普勒超声参数联合胎盘生长因子(PLGF)对早发型胎儿生长受限(FGR)的预测价值。方法选取早发型FGR孕妇80例为FGR组,另选取同期产检健康孕妇50例为对照组。在孕11~13周+6对所有研究对象进行三维能量多普勒超声检查,收集... 目的探讨三维能量多普勒超声参数联合胎盘生长因子(PLGF)对早发型胎儿生长受限(FGR)的预测价值。方法选取早发型FGR孕妇80例为FGR组,另选取同期产检健康孕妇50例为对照组。在孕11~13周+6对所有研究对象进行三维能量多普勒超声检查,收集胎盘容积(PV)、血管化指数(VI)、血流指数(FI)、血管化-血流指数(VFI)等指标。在孕14~16周+6检测所有研究对象血清PLGF水平。结果FGR组的PV、VI、FI、VFI以及血清PLGF水平均低于对照组,差异有统计学意义(P<0.05)。多元Logistic回归方程分析显示,PV、VI、FI、VFI以及血清PLGF水平过低是早发型FGR的危险因素(P<0.05)。受试者工作特征(ROC)曲线分析显示,PV、VI、VFI以及血清PLGF均对早发型FGR有一定的预测价值,曲线下面积分别为0.723(95%CI:0.629~0.817)、0.776(95%CI:0.693~0.860)、0746(95%CI:0.653~0.839)、0.799(95%CI:0.713~0.884),FI对早发型FGR的预测价值一般,曲线下面积为0.625(95%CI:0.524~0.725)。经分析显示,PLGF联合VI以及PLGF联合VFI对早发型FGR的预测价值较好,PLGF联合VI的敏感度、特异度和约登指数分别为86.25%、76.00%、0.623,PLGF联合VFI的敏感度、特异度和约登指数分别为81.25%、80.00%、0.613。结论三维能量多普勒超声参数联合PLGF对早发型FGR有一定的预测价值,可用于临床筛查早发型FGR高风险人群。 展开更多
关键词 胎儿生长受限 三维能量多普勒超声 胎盘生长因子 预测价值
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以胎儿生长受限为首发症状子痫前期的临床特征及危险因素
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作者 李秀芳 高伟娜 赵先兰 《河南医学研究》 CAS 2024年第9期1545-1549,共5页
目的探讨以胎儿生长受限(FGR)为首发症状子痫前期的临床特征及危险因素,为产前咨询及处理提供参考。方法选取2018年1月至2023年1月至郑州大学第一附属医院产科住院的120例FGR患者为研究对象,其中40例患者并发子痫前期作为研究组,80例患... 目的探讨以胎儿生长受限(FGR)为首发症状子痫前期的临床特征及危险因素,为产前咨询及处理提供参考。方法选取2018年1月至2023年1月至郑州大学第一附属医院产科住院的120例FGR患者为研究对象,其中40例患者并发子痫前期作为研究组,80例患者未并发子痫前期作为对照组,回顾性对比分析两组患者的一般特征、妊娠期合并症、母体及围产儿结局等资料。采用logistic回归模型分析FGR并发子痫前期的危险因素,并计算ROC曲线下面积分析预测子痫前期的效能。结果(1)一般特征:研究组与对照组孕前体重指数、诊断FGR时孕周比较,差异有统计学意义(P<0.05);两组年龄、初产妇占比、有无规律产检、是否辅助生殖、有无不良孕产史比较,差异无统计学意义(P>0.05)。(2)妊娠期合并症:研究组与对照组蛋白尿、抗磷脂抗体阳性率比较,差异有统计学意义(P<0.05);两组合并妊娠高血糖、甲状腺功能减退、脐带扭转、子宫畸形、羊水少、贫血比较,差异无统计学意义(P>0.05)。(3)母体妊娠结局:两组患者的妊娠并发症、住院天数、剖宫产率比较,差异有统计学意义(P<0.05)。(4)新生儿结局:研究组中医疗性引产6例,对照组4例;两组患者产时存活新生儿中早产、分娩孕周、新生儿体重比较,差异有统计学意义(P<0.05);研究组中新生儿并发症脑室出血、新生儿窒息、呼吸窘迫综合征、代谢性酸中毒的发生概率高于对照组,差异有统计学意义(P<0.05),但两组围产儿出生后死亡率比较差异无统计学意义(P>0.05)。(5)logistic回归分析显示:诊断FGR时孕周、孕前体重指数是以FGR为首发症状子痫前期的独立危险因素;ROC曲线分析显示,诊断FGR时孕周(AUC=0.817,95%CI为0.723~0.911)和孕前体重指数(AUC=0.714,95%CI为0.621~0.807)可用于子痫前期的风险预测,且两者联合预测(AUC=0.860,95%CI为0.785~0.934)的效能优于单一指标。结论FGR并发子痫前期可增加母儿不良妊娠结局,诊断FGR时孕周和孕前体重指数是子痫前期的独立危险因素,加强对预警因素的监测和处理,有助于早期识别子痫前期,改善母儿预后。 展开更多
关键词 胎儿生长受限 子痫前期 妊娠结局 预警因素
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英语学习者网络学习行为与教学对策实证研究
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作者 杨圣柱 王艳 姜睿萍 《黑龙江教师发展学院学报》 2024年第3期74-77,共4页
网络学习行为分析着眼于探究在线学习者内隐学习的偏好,发现零散学习行为中的底层规则,洞察各类行为的内部联系。在分析研究背景和进行文献综述的基础上,对英语学习者网络学习行为与教学对策展开实证研究。最后,得出结论,即应从学习者... 网络学习行为分析着眼于探究在线学习者内隐学习的偏好,发现零散学习行为中的底层规则,洞察各类行为的内部联系。在分析研究背景和进行文献综述的基础上,对英语学习者网络学习行为与教学对策展开实证研究。最后,得出结论,即应从学习者内驱力、教师信息素养、课程大纲和平台设计等方面进行提高和创新,为搭建自适应教学平台和促进学生个性化学习提供便利。 展开更多
关键词 网络学习行为 英语学习者 因子分析 教学对策
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