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991.
This study presents a comparative assessment of severe accident risks in the energy sector, based on the historical experience of fossil (coal, oil, natural gas, and LPG [Liquefied Petroleum Gas]) and hydro chains contained in the comprehensive Energy-related Severe Accident Database (ENSAD), as well as Probabilistic Safety Assessment (PSA) for the nuclear chain. Full energy chains were considered because accidents can take place at every stage of the chain. Comparative analyses for the years 1969–2000 included a total of 1870 severe (≥ 5 fatalities) accidents, amounting to 81,258 fatalities. Although 79.1% of all accidents and 88.9% of associated fatalities occurred in less developed, non-OECD countries, industrialized OECD countries dominated insured losses (78.0%), reflecting their substantially higher insurance density and stricter safety regulations. Aggregated indicators and frequency-consequence (F-N) curves showed that energy-related accident risks in non-OECD countries are distinctly higher than in OECD countries. Hydropower in non-OECD countries and upstream stages within fossil energy chains are most accident-prone. Expected fatality rates are lowest for Western hydropower and nuclear power plants; however, the maximum credible consequences can be very large. Total economic damages due to severe accidents are substantial, but small when compared with natural disasters. Similarly, external costs associated with severe accidents are generally much smaller than monetized damages caused by air pollution. 相似文献
992.
Karen W. Holmes Dar A. Roberts Stuart Sweeney Izaya Numata Eraldo Matricardi† Trent W. Biggs Getulio Batista‡ Oliver A. Chadwick 《Global Change Biology》2004,10(5):796-814
Regional and global environmental modeling depend on soil data for input layers or parameterization. However, randomly located observations, such as provided by agricultural databases, are not always representative of trends identified in field studies conducted under carefully controlled conditions. Many researchers lament the paucity of soil profile data in Amazônia, and suggest that given more data, regional studies would more closely approximate field research results. We assess the ability of a well‐populated regional database collected in the southwestern Brazilian Amazon to reproduce expected biogeochemical trends associated with forest clearing and pasture establishment, and explore the ramifications of relying on independently collected soil data for regional modeling. The Soteron database includes analyses of approximately 3000 soil cores collected for zoning purposes in the state of Rondônia. Pasture ages were determined from a time series of Landsat TM images classified using spectral mixture analysis. Although regional averages showed some of the temporal trends expected based on field study results (e.g. increase in pH following forest clearing), the trends were not statistically significant. Stratification by precipitation and other variables showed pasture age to be important but difficult to separate from other potential controls on soil conditions, mainly because of the reduced number of observations in each stratum. Using multiple regression, which permitted the inclusion of all potential explanatory factors and interactions, pasture age was shown to be a statistically significant predictor of soil conditions. However, the expected temporal sequence of changes documented by field chronosequence studies could not be reproduced. Properties dominated by large‐scale environmental gradients – pH, sum of base cations, aluminum saturation, and exchangeable calcium – were moderately well modeled, while those more strongly linked to dynamic spatially heterogeneous processes such as biological cycling and land management, particularly organic carbon and nitrogen, could not be modeled. Management‐induced soil changes occur at too fine a scale to be captured by most maps, and the relative changes are small compared with spatial heterogeneity caused by controls on soil development over large regions. Therefore, regardless of whether chronosequence‐derived models of biogeochemical response to land‐cover change are correct, the results of these models will not lead to spatially explicit maps that can be validated by regional reconnaissance, nor will they facilitate realistic predictions of the regional biogeochemical consequences of land‐cover change. The change from local to regional scale entails a change in the relative importance of processes controlling soil property behavior. 相似文献
993.
Plant membrane proteome databases 总被引:6,自引:0,他引:6
Rainer Schwacke Ulf-Ingo Flügge Reinhard Kunze 《Plant Physiology and Biochemistry》2004,42(12):1023-1034
In all living organisms transmembrane (TM) proteins are crucially involved in many physiological processes and constitute 20-30% of the proteome. An important class of TM proteins are transporters that interconnect biochemical pathways across the plasma membrane and intracellular membranes, e.g. the mitochondrial membranes and chloroplast envelope membranes. In recent years, bioinformatical tools to predict TM domains and subcellular localization were developed and used to analyze the first complete plant genomes of Arabidopsis and rice. This review focuses on plant TM proteome databases that compile topology and intracellular targeting predictions and different kinds of experimental data. In addition, other web sites are discussed that contribute useful experimental and/or bioinformatical data. 相似文献
994.
Gillian Barker 《Biology & philosophy》2008,23(1):1-25
Two critiques of simple adaptationism are distinguished: anti-adaptationism and extended adaptationism. Adaptationists and
anti-adaptationists share the presumption that an evolutionary explanation should identify the dominant simple cause of the
evolutionary outcome to be explained. A consideration of extended-adaptationist models such as coevolution, niche construction
and extended phenotypes reveals the inappropriateness of this presumption in explaining the evolution of certain important
kinds of features—those that play particular roles in the regulation of organic processes, especially behavior. These biological
or behavioral ‘levers’ are distinctively available for adaptation and exaptation by their possessors and for co-optation by
other organisms. As a result they are likely to result from a distinctive and complex type of evolutionary process that conforms
neither to simple adaptationist nor to anti-adaptationist styles of explanation. Many of the human features whose evolutionary
explanation is most controversial belong to this category, including the female orgasm.
相似文献
Gillian BarkerEmail: |
995.
The Plant Gene Index (PlantGI) database is developed as a web-based search system with search capabilities for keywords to provide information on gene indices specifically for agricultural plants. The database contains specific Gene Index information for ten agricultural species, namely, rice, Chinese cabbage, wheat, maize, soybean, barley, mushroom, Arabidopsis, hot pepper and tomato. PlantGI differs from other Gene Index databases in being specific to agricultural plant species and thus complements services from similar other developments. The database includes options for interactive mining of EST CONTIGS and assembled EST data for user specific keyword queries. The current version of PlantGI contains a total of 34,000 EST CONTIGS data for rice (8488 records), wheat (8560 records), maize (4570 records), soybean (3726 records), barley (3417 records), Chinese cabbage (3602 records), tomato (1236 records), hot pepper (998 records), mushroom (130 records) and Arabidopsis (8 records). AVAILABILITY: The database is available for free at http://www.niab.go.kr/nabic/. 相似文献
996.
杨汉林 《中国实验动物学杂志》2008,(11):67-69
制订福建省2008~2010年实验动物技术服务基地建设规划,是促进实验动物科技资源的合理配置与共享和实验动物学科发展的需求。本文根据对全省实验动物科技现状的调查,在《福建省"十一五"科技发展规划纲要》的基础上,提出制订福建省2008~2010年实验动物技术服务基地建设规划的思路,包括指导思想、工作目标、工作重点和对策措施。通过整合、优化和提升实验动物现有资源,建设技术先进、管理规范、开放运行的实验动物技术服务平台,成为我省生命科学、生物科学、食品、化妆品、保健品等相关研究与技术开发提供公共服务的动物实验基地,实现全省范围的服务共享。 相似文献
997.
以"活性肽搜寻与蛋白模拟水解数据库"为工具,选择胃蛋白酶+胰蛋白酶和碱性蛋白酶对大豆7S蛋白进行模拟水解,得出不同水平的ACE抑制肽肽段,并通过实验比较以上蛋白酶水解物ACE抑制活性的高低。模拟水解结果表明,胃蛋白酶+胰蛋白酶水解大豆7S蛋白得到较多的ACE抑制肽肽段,实验结果表明,碱性蛋白酶水解物ACE抑制活性最大,为73.0965%。 相似文献
998.
小伞山羊草中新型avenin-like基因的克隆及真核表达载体的构建 总被引:1,自引:0,他引:1
目的:克隆小伞山羊草中新型avenin-like(类燕麦储藏蛋白)基因,揭示avenin-like基因的表达模式,并构建avenin-like基因真核胚乳特异性表达载体。方法:利用RT-PCR方法揭示avenin-like基因的表达模式,并用PCR方法从小伞山羊草中克隆新型avenin-like基因;将克隆的avenin-like基因插入表达载体pLRPT构建真核表达载体pLRPT-avel,并经酶切和测序鉴定。结果:avenin-like基因在胚乳中特异性表达;克隆得到新型avenin-like基因,并构建了其真核胚乳特异性表达载体。结论:新型avenin-like基因的克隆及其真核表达载体的构建,为小麦品质改良提供了研究基础。 相似文献
999.
水稻矮缩病毒基因组数据库的构建 总被引:9,自引:0,他引:9
二级数据库的构建是生物信息学新的重要领域。目前部分生物的基因组序列测定完成后,正在进行广泛而深入的结构和功能研究,使二级数据库的重要性显得日益突出。水稻矮缩病毒是一种在日本、中国和东南亚感染水稻的病原微生物,给农业生产造成很大损失。根据国际和国内对水稻矮缩病毒基因组的研究,利用已有的基因序列和结构、功能等方面的数据,以计算机网络为载体,参考国际通用数据库的格式,尝试建立一个简洁的、友好的通用性好而且专用性强的二级数据库:水稻矮缩病毒基因组数据库。希望能够为研究普通水稻矮缩病毒的粒子结构、基因表达调控、致病机理和防治方法提供一个良好的工具,为从事水稻矮缩病理论和应用研究的工作者提供方便和帮助,并为探索二级数据库的构建积累经验。 相似文献
1000.