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地伐西匹翻转辛卡利特对抗吗啡对大鼠空肠活动的作用(英文)
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作者 徐满英哈尔滨医科大学生理教研室 杨新平 +2 位作者 金宏波 杨春晓 杨立庄 《中国药理学报》 CSCD 1999年第5期419-422,共4页
目的:研究辛卡利特(sincalide)的抗吗啡作用及其作用机制,方法:采用了同步描记大鼠离体空肠电生理与机械活动的方法。结果:乙酰胆碱(ACh)可使大鼠离体空肠峰波振幅增大、数目增多,其收缩幅度随之增大,两者呈正相关,相反地,吗啡能抑制AC... 目的:研究辛卡利特(sincalide)的抗吗啡作用及其作用机制,方法:采用了同步描记大鼠离体空肠电生理与机械活动的方法。结果:乙酰胆碱(ACh)可使大鼠离体空肠峰波振幅增大、数目增多,其收缩幅度随之增大,两者呈正相关,相反地,吗啡能抑制ACh的加强作用,呈负相关,辛卡利特能对抗吗啡的作用,即峰波振幅、数目再次增加,收缩幅度也随之增加。在此基础上,CCK-A受体拮抗剂地伐西匹能翻转辛卡利特的抗吗啡作用,结论:辛卡利特对抗吗啡抑制ACh加强空肠活动的作用,推测该作用是通过CCK-A受体实现的。 展开更多
关键词 辛卡利特 地伐西匹 吗啡 电生理学 肌肉收缩
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OPGW光缆的设计与施工探讨 被引量:1
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作者 任建川 《中国高新技术企业》 2011年第36期53-55,共3页
OPGW(Optical Ground Wire)被为光纤复合地线、光纤架空地线或地线复合光缆等。文章介绍了光纤复合地线(OPGW)的设计条件,接着重点阐述了OPGW在结构型式、热稳定性设计、金具及抗震设计和避雷设计等方面的设计要点,最后就电力方面施工... OPGW(Optical Ground Wire)被为光纤复合地线、光纤架空地线或地线复合光缆等。文章介绍了光纤复合地线(OPGW)的设计条件,接着重点阐述了OPGW在结构型式、热稳定性设计、金具及抗震设计和避雷设计等方面的设计要点,最后就电力方面施工的具体情况探讨了在实际施工过程中的注意事项。 展开更多
关键词 OPGW 短路电流 热稳定设计 光纤复合地伐设计 光纤接续施工工艺
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Analysis of Land Degradation in Ethiopia and Countermeasures 被引量:2
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作者 汪洋 《Agricultural Science & Technology》 CAS 2010年第6期152-154,共3页
In Ethiopia soil conservation is primarily meant to improve agriculture production.Therefore,assessment of the existing erosion hazards and classifying the land according to its capability are essential.This paper dep... In Ethiopia soil conservation is primarily meant to improve agriculture production.Therefore,assessment of the existing erosion hazards and classifying the land according to its capability are essential.This paper depicts the land degradation status and causes,through an integrated assessment,and some measures to alleviate the problem are proposed. 展开更多
关键词 Land degradation Soil erosion DEFORESTATION Soil conservation MEASURE
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Dynamic change of arborous species diversity in natural secondary forests after selective cutting on the north slope of Changbai Mountain, Northeast China
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作者 金永焕 周莉 +3 位作者 谷会岩 代力民 申光日 刘军 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期299-302,共4页
The community characteristics of natural secondary forests on the north slope of Changbai Mountain after selective cutting were investigated, and the dynamics of arborous species diversity during the restoration perio... The community characteristics of natural secondary forests on the north slope of Changbai Mountain after selective cutting were investigated, and the dynamics of arborous species diversity during the restoration period of 28 years were studied. The results showed that the arborous species richness (S) had little change and kept the range of 18-22 all along, the Simpson index (D) of the secondary layer and regeneration layer and whole stand had similar trends of change, but that of the canopy layer descended slowly in initial 15 years and had little change later, and the change of diversity index was not obvious and the Shannon-Wiener index (H? fluctuated in a very small scopes (H±10%). 展开更多
关键词 Arborous species diversity Natural secondary forests Selective cutting Northeast China
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Comparison and Analysis of Agricultural and Forest Land Changes in Typical Agricultural Regions of Northern Mid-latitudes 被引量:3
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作者 LIU Tingxiang ZHANG Shuwen +1 位作者 TANG Junmei LI Tianqi 《Chinese Geographical Science》 SCIE CSCD 2013年第2期163-172,共10页
The northeastern China, the United States, and the western Europe are important agricultural regions both on the global and regional scales. The westem Europe has a longer history of agricultural land development than... The northeastern China, the United States, and the western Europe are important agricultural regions both on the global and regional scales. The westem Europe has a longer history of agricultural land development than the eastem United States. These two regions have changed from the deforestation and reclamation phase in the past to the current land abandonment and reforestation phase. Compared with the two regions, large-scale land exploitation has only been practiced in the northeastern China during the last century. After a short high-intensity deforestation and reclamation period, agricultural and forest lands are basically in a dynamic steady state. By comparing domestic and international agro-forestry development and considering the ecological environment and socio-economic bene- fits that can be derived from agro-forestry, this paper suggests that large area of reforestation would be inevitable in future though per- sistent and large agricultural demand in coming decades even more. And local reforestation at slope farmland with ecological vulner- ability should be imperative at present to avoid severer damage. At the same time, from the perspective of Land Change Science, the results demonstrate that the research on land use change in the agro-forestry ecotone is typical and critical, particularly those dealing with the analysis of spatial and temporal characteristics and the simulation of climate, hydrology, and other environmental effects. 展开更多
关键词 agricultural land change forest land change REFORESTATION agro-forestry ecotone northeastern China Europe United States
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Mountain Wood vs. Lowland Wood Harvesting Methods: An Ecological Case Study
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作者 Anton Kraler Verena Krismer Georg Wieland 《Journal of Civil Engineering and Architecture》 2014年第1期89-99,共11页
Are Austrian mountain wood harvesting techniques more ecological than techniques applied in the lowlands of southern Germany? For this comparative study, the authors selected the area of Lower Bavaria for lowland woo... Are Austrian mountain wood harvesting techniques more ecological than techniques applied in the lowlands of southern Germany? For this comparative study, the authors selected the area of Lower Bavaria for lowland wood, as a great deal of wood is imported from this region to western Austria. At first, the felling area is described for both regions, from forest site to sawmill. Thereby, the authors create mean values related to timber harvesting and transportation, which are applicable to the whole of western Austria and Lower Bavaria, southern Germany. Secondly, the eco-balance of mountain and lowland wood is established. It is based on the following impact categories: global warming potential, acidification potential, eutrophication potential, ozone depletion potential and non-renewable primary energy. The environmental impact is more expressive if the results are applied to a specific construction part (i.e., glued laminated timber-ceiling). Our research study showed the eco-balance of western Austrian mountain wood is more favourable than the environmental impact of harvesting lowland wood in southern Germany. 展开更多
关键词 Mountain wood lowland wood harvesting techniques eco-balance global warming potential.
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Possibilities of GPS Kinematic Measurements for Geological Survey in East Slovakia
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作者 Vladimír Sedlák Viera Huríková Sona Molíková 《Geo-Spatial Information Science》 2002年第4期21-25,共5页
This paper deals with transformation procedures for observed GPS data from the world geodetic system WGS84 into the national geodetic grid datum SUTCN (system of united trigonometric cadaster network) and Baa(the B... This paper deals with transformation procedures for observed GPS data from the world geodetic system WGS84 into the national geodetic grid datum SUTCN (system of united trigonometric cadaster network) and Baa(the Baltic Sea after adjustment).Transformation from WGS84 into SUTCN is performed most frequently by means of the 7element Helmert transformation with three identical points.Geodetic network was adjusted by two ways. 展开更多
关键词 kinematic GPS technology 3D coordinate transformations free adjustment adjustment with constraints
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Comparison of Development of Housing Construction in Regions of Slovakia and Czech Republic
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作者 Zora Petrakova Martina Jurigova Jan Dvorsky 《Chinese Business Review》 2016年第6期282-289,共8页
Cities and municipalities are involved in the economic development of the whole country. One of the priorities of mayors is the usefulness of spatial disproportions of area as well as the structure and development of ... Cities and municipalities are involved in the economic development of the whole country. One of the priorities of mayors is the usefulness of spatial disproportions of area as well as the structure and development of housing construction. They are natural canters of public and commercial services. The aim of the article is to determine if the geographic location of the region influences the number of new apartments with planning permission and completed apartments with a completion approval by using the methods of mathematical statistics "Analysis of variance". Meaning of the geographical location of the region as a factor, which influences the construction of apartments as well as regional differences in selected Central European countries, is subject of the conclusions of the paper. 展开更多
关键词 region analysis of variance planning permission completion approval development of housing Kruskal-Wallis test
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Multi-temporal forest cover dynamics in Kashmir Himalayan region for assessing deforestation and forest degradation in the context of REDD+ policy 被引量:2
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作者 Akhlaq Amin WANI Pawan Kumar JOSHI +1 位作者 Ombir SINGH Sumera SHAFI 《Journal of Mountain Science》 SCIE CSCD 2016年第8期1431-1441,共11页
The role of forests is being actively considered under the agenda of REDD+ (Reducing Emissions from Deforestation and Forest Degradation plus) aimed at reducing emissions related to changes in forest cover and fore... The role of forests is being actively considered under the agenda of REDD+ (Reducing Emissions from Deforestation and Forest Degradation plus) aimed at reducing emissions related to changes in forest cover and forest quality. Forests in general have undergone negative changes in the past in the form of deforestation and degradation, while in some countries positive changes are reported in the form of conservation, sustainable management of forests and enhancement of carbon stock. The present study in the Kashmir Himalayan forests is an effort to assess historical forest cover changes that took place from 1980 to 2009 and to predict the same for 2030 on the basis of past trend using geospatial modeling approach. Landsat data (Multispectral Scanner (MSS), Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+)) was used for the years 1980, 199o and (2001, 2009) respectively and change detection analysis between the dates was performed. The maps generated were validated through ground truthing. The study area (3375.62 km^2) from 1980-2009 has uffered deforestation and forest degradation of about 126 km^2 and 239.02 km^2 respectively which can be claimed under negative options of REDD+, while as the area that experienced no change (1514 km^2) can be claimed under conservation. A small area (23.31 km^2) observed as positive change can be claimed under positive options. The projected estimates of forest cover for 2030 showed increased deforestation and forest degradation on the basis of trend analysis using Cellular Automata (CA) Markov modeling. Despite the fact that country as a whole has registered a net positive change in the past few decades, but there are regions like Kashmir region of western Himalaya which have constantly undergoing deforestation as well as degradation in the past few decades. 展开更多
关键词 DEFORESTATION Degradation Coniferous forests Carbon emission HIMALAYA
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Landform Instability and Land-use Dynamics in Tropical High Mountains, Central Mexico 被引量:2
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作者 GARCíA-ROMERO Arturo ACEVES-QUESADA José Fernando ARREDONDO-LEóN Carlos 《Journal of Mountain Science》 SCIE CSCD 2012年第3期414-430,共17页
This investigation is an analysis of the influence of landform instability on the distribution of land-use dynamics in a hydrographical basin, located in the Mexican Volcanic Belt mountain range (central Mexico), curr... This investigation is an analysis of the influence of landform instability on the distribution of land-use dynamics in a hydrographical basin, located in the Mexican Volcanic Belt mountain range (central Mexico), currently affected by substantial changes in land use and deforestation. A landform map was produced, in addition to seven attribute maps - altimetry, drainage density, slope, relief energy, potential erosion, geology and tectonics - which were considered as factors for determining landform instability through Multi-criteria Evaluation Analysis. Likewise, the direction and rhythm of land-use dynamics were analyzed in four dates - between 1976 and 2000 - and cross tabulations were made between them, in order to analyze the trends and processes of land-use dynamics. Afterwards, the databases obtained were cross tabulated with the landform variables to derive areas, percentages and correlation indices. In the study area, high-instability landforms are associated with most ancient volcanic and sedimentary landforms, where high altitude, drainage density, slope and potential to develop gravitational and fluvial processes are the major factors favouring a land-use pattern, dominated by the conservation of extensive forest land, abandonment of human land use and regeneration of disturbed areas. In contrast, low-instability landforms correspond to alluvial plains and lava hills covered by pyroclasts, where low potential erosion to develop fluvial processes, added to water and soil availability and accessibility, have favoured a land-use pattern dominated by the expansion of agroforestry plantations and human settlements, showing a marked trend towards either intensification or permanence of the current land use and with little abandonment and regeneration. 展开更多
关键词 Landform instability Multi-criteriaEvaluation Analysis Land-use change and processes Tuxpan River Basin
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Socio-Economic Brand "Carpathians" in the Context of Tourism Industry Development in Countries of Central and East Europe
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作者 Fedir Shandor 《Chinese Business Review》 2015年第4期186-191,共6页
Brand in terms of strategy is a way of relationships between the organization and its target groups, aimed at removing a priori existing conflict. Therefore, formation of a new socio-economic brand "Carpathians", wh... Brand in terms of strategy is a way of relationships between the organization and its target groups, aimed at removing a priori existing conflict. Therefore, formation of a new socio-economic brand "Carpathians", which joins a mountain system in the eastern part of Central Europe, Ukraine, Hungary, Poland, Slovakia, Romania, Serbia, and Austria, will help create a new image of Carpathians and implementation of programs aimed at the increase of investment activities, building confidence to domestic producers and creating programs to attract tourists to the most profitable tourist areas, in particular. 展开更多
关键词 brands traditional products famous brand successful export
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Forest Conflict on the Forest Resources Management between Indigenous People and the Logging Company in Small Island
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作者 Gun Mardiatmoko Thomas Melianus Silaya Jan Willem Hatulesila 《Journal of Agricultural Science and Technology(B)》 2015年第4期257-268,共12页
Many conflicts are reported in small islands mainly in Eastern region of Indonesia and it is needed to conflict resolution in the forest sector. The research has been conducted on forest conflict in the small island o... Many conflicts are reported in small islands mainly in Eastern region of Indonesia and it is needed to conflict resolution in the forest sector. The research has been conducted on forest conflict in the small island of Yamdena. The aims of the research were: (1) to determine the customary rights of indigenous peoples to the forest area that was claimed as theirs according to the applicable rules and regulations; (2) to study the causes of conflict between indigenous peoples and the logging company; (3) to analyze the policy in the forest resources management on the customary land. This research is qualitative and uses a case study methodology. Data collection methods used include semi-structured interviews, participant observation and focus group discussion (FGD). The results showed that indigenous peoples whose livelihood is highly dependent on the forest were most threatened because of forest exploitation of their traditional land by the logging company. Handling of the conflict potential in the forest resources management in Yamdena island was approached through use of traditional laws, involving all the relevant parties to the conflict. The forest management either by indigenous peoples or the logging company is no longer focused on the timber harvesting but more on conservation aspects. 展开更多
关键词 Forest conflict forest concession customary rights social forestry.
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Deforestation Trends and Spatial Modelling of its Drivers in the Dry Temperate Forests of Northern Pakistan–A Case Study of Chitral 被引量:3
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作者 Khuram Shehzad Faisal M.Qamer +2 位作者 MSR Murthy Sawaid Abbas Laxmi D.Bhatta 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1192-1207,共16页
Deforestation is a major environmental challenge in the mountain areas of Pakistan. The study assessed trends in the forest cover in Chitral tehsil over the last two decades using supervised land cover classification ... Deforestation is a major environmental challenge in the mountain areas of Pakistan. The study assessed trends in the forest cover in Chitral tehsil over the last two decades using supervised land cover classification of Landsat TM satellite images from 1992, 2000, and 2009, with a maximum likelihood algorithm. In 2009, the forest cover was 10.3% of the land area of Chitral(60,000 ha). The deforestation rate increased from 0.14% per annum in 1992–2000 to 0.54% per annum in 2000–2009, with 3,759 ha forest lost over the 17 years. The spatial drivers of deforestation were investigated using a cellular automaton modelling technique to project future forest conditions. Accessibility(elevation, slope), population density, distance to settlements, and distance to administrative boundary were strongly associated with neighbourhood deforestation. A model projection showed a further loss of 23% of existing forest in Chitral tehsil by 2030, and degradation of 8%, if deforestation continues at the present rate. Arandu Union Council, with 2212 households, will lose 85% of its forest. Local communities have limited income resources and high poverty and are heavily dependent on non-timber forest products for their livelihoods. Continued deforestation will further worsen their livelihood conditions, thus improved conservation efforts are essential. 展开更多
关键词 Remote sensing Drivers of deforestation Cellular automata
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Forest and Soil Carbon Stocks, Pools and Dynamics and Potential Climate Change Mitigation in Nepal 被引量:1
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作者 Shrestha Him Lal Roshan M. Bajracharya Bishal K. Sitaula 《Journal of Environmental Science and Engineering(B)》 2012年第6期800-811,共12页
The degradation of forest and soil contribute significantly to carbon emission to the atmosphere leading to the build-up of carbon dioxide in atmosphere and contributing to global warming. Consequences of climate chan... The degradation of forest and soil contribute significantly to carbon emission to the atmosphere leading to the build-up of carbon dioxide in atmosphere and contributing to global warming. Consequences of climate change are not only the rise in global temperatures, but also changes in the precipitation patterns, which could affect agricultural production, food security, human health and long-term ecosystem properties balance. The deforestation and land degradation are major sources of GHG (greenhouse gas) emissions. International negotiations and dialogues on REDD+ mechanism are held for both national and local level mitigation policies formulation for the reduction of carbon emission from land use, land use change and forestry sector. The reduction of emissions from fossil fuel combustion and avoidance of deforestation and forest/land degradation constitute lasting and long-term solutions for mitigating climate change. There is an urgent need of relevant and efficient methods of measuring forest and soil carbon through application of the latest geospatial technologies, i.e., GIS (geographic information system), Remote Sensing and LiDAR (Light Detection and Ranging). These technologies can support the precise measurement of carbon stocks, as well as, offer cost effective and interoperable data generation methods. The REDD+ mechanism is being promoted worldwide mainly to reduce the diminishing of forest in developing countries. Such an approach must consider use rights, sustainable management of forests, ensuring and safe-guarding the benefit sharing mechanism and good governance, along with the legal framework and local livelihood concerns. 展开更多
关键词 Carbon pool land use change MITIGATION REDD+
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天山赋
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作者 王治宇 《中华辞赋》 2018年第8期27-27,共1页
西域胜景,天山高崇。横贯东西之五千余里,纵覆南北之六百彫弓。极纬山系,远洋冰峰。襟草原而裾荒漠,引天河而汇流虹。三列平行,连波西走;宏胸海纳,褶皱合纵。逆风南坡,旷漠绵延而冰草缀;顺风北麓,针林迤逦而肥绿茏。九宇流云,罗彩添玉... 西域胜景,天山高崇。横贯东西之五千余里,纵覆南北之六百彫弓。极纬山系,远洋冰峰。襟草原而裾荒漠,引天河而汇流虹。三列平行,连波西走;宏胸海纳,褶皱合纵。逆风南坡,旷漠绵延而冰草缀;顺风北麓,针林迤逦而肥绿茏。九宇流云,罗彩添玉练之带;三河融雪,珍禽闹锦绣之宫。八骏马以西行,穆王游历;天山池以宴会,王母恭逢。雪海纯莲圣洁而独帜,天国神民异禀于东穹。观夫白山傲凌,西陲茕孑。惟昔天工,斯乃地伐。 展开更多
关键词 东穹 褶皱 锦绣 波西 天山 雪海 雪融 地伐 冰峰
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Protective effects of selective and non-selective cyclooxygenase inhibitors in an animal model of chronic stress 被引量:1
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作者 Anil Kumar Beenta Kumari Puneet Kumar 《Neuroscience Bulletin》 SCIE CAS CSCD 2010年第1期17-27,共11页
Objective Cyclooxygenase isoenzyme is known to be expressed in different regions of brain, and is mainly used for the treatment of pain and inflammation. Recently, it is proposed that cyclooxygenase isoenzyme may also... Objective Cyclooxygenase isoenzyme is known to be expressed in different regions of brain, and is mainly used for the treatment of pain and inflammation. Recently, it is proposed that cyclooxygenase isoenzyme may also play a key role in the pathophysiology of various brain-related disorders. The present study was aimed to explore the protective effect of cyclooxygenase inhibitors on stress by using an animal model of chronic stress. Methods The animals were forced to swim individually for a period of 6 min every day for 15 d. Then, the behavior (locomotor activity, anxiety and memory) and biochemical (lipid peroxidation, nitrite level, reduced glutathione, and catalase) alterations were assessed. Results Forced swimming for 15 d caused impaired locomotor activity, anxiety-like behavior and decreased percentage of memory retention, as compared to na?ve mice (without chronic fatigue treatment). Biochemical analysis revealed significant increases in lipid peroxidation and nitrite level, while levels of reduced glutathione and catalase activity were both decreased. Chronic treatment with naproxen (14 mg/kg, i.p.), rofecoxib (5 mg/kg, i.p.), meloxicam (5 mg/kg, i.p.), nimesulide (5 mg/kg, i.p.) and valdecoxib (10 mg/kg, i.p.) significantly attenuated these behavioral and biochemical (oxidative damage) alterations in chronic-stressed mice. Conclusion The cyclooxygenase inhibitors could be used in the management of chronic fatigue-like conditions. 展开更多
关键词 chronic fatigue syndrome NAPROXEN VALDECOXIB ROFECOXIB NIMESULIDE MELOXICAM
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