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101.
Roberto La Rovere Aden Aw‐Hassan Francis Turkelboom Richard Thomas 《Development and change》2006,37(3):627-648
Agricultural research in marginal dry areas can contribute to reducing poverty through the development of technological, institutional and policy options for poor farmers. Such research should address diversified opportunities and development pathways. This article analyses the diversity of livelihood strategies of rural people living in the Khanasser Valley in northwestern Syria, an area that is typical of marginal drylands. It proposes an operational classification of households based on their different livelihood strategies, applying an integrated methodology within a Sustainable Livelihoods framework. Households are classified into three clusters: agriculturists, labourers and pastoralists. The article examines the diversity of livelihoods involved, and considers where and how research should be directed to have greatest impact on poverty. Given that rural households are not homogeneous but dynamic entities, with diverse assets, capabilities and opportunities, the definition of household typologies can help to target development research. The article concludes that while agriculturists benefit most, poor labourers with enough land can also gain from pro‐poor agricultural research. The poorest households with little land, and pastoralists, benefit little or only indirectly. 相似文献
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103.
Patrizia Santi Alberto Renzulli Fabrizio Antonelli Antonio Alberti 《Journal of archaeological science》2009,36(11):2493-2501
Soapstones (talc-bearing schists) and garnet chlorite schist artifacts found in Medieval archaeological sites of Tuscany (Central Italy) were classified, in order to define provenance of the different lithotypes. In Italy and throughout the Central Europe, these greenschist facies metamorphic rocks are generally known, among the archaeologists, as the pietra ollare from the Alps. The investigated Tuscan archaeological sites are between 6 and 13th century AD and were strictly linked, in that period, to the well defined network trade running along Tyrrhenian coast. Samples come from little containers used for cooking and preserving food and showing traces of lathe manufacturing at their sidewalls. According to modal mineralogy, petrographic texture, XRD, SEM-EDS and whole rock chemistry we recognised, among the 18 studied findings, three different petrographic groups of the Alpine pietra ollare. (i) Fine grained magnesite talc schists (i.e. soapstones) from outcrops of the Central Alps located in the Valchiavenna area. (ii) Garnet chlorite schists from the Valle d'Aosta region. (iii) Amphibole talc schists (i.e. soapstones) with a provenance in the Ticino area. It is worth noting that artifacts of pietra ollare lithotypes from the Western Alps (i.e. garnet chlorite schists and amphibole talc schists) were not detected in the archaeological sites of the Middle Adriatic coast of the Central Italy, belonging to the same Medieval time interval. This emphasises that the petrographic groups of pietra ollare from the Alps spread to the south of the Po Plain according to Western and Eastern trade along the Italian Peninsula, using respectively, the Tyrrhenian and the Adriatic Sea commercial routes. 相似文献
104.
Elena Gigli Morten Rasmussen Sergi Civit Antonio Rosas Marco de la Rasilla Javier Fortea M. Thomas P. Gilbert Eske Willerslev Carles Lalueza-Fox 《Journal of archaeological science》2009,36(12):2676-2679
Neandertal skeletal remains are usually contaminated with modern human DNA derived from handling and washing of the specimens during excavation. Despite the fact that the distinct Neandertal haplotypes allow the design of specific primer pairs, for instance in most of the mitochondrial DNA (mtDNA) hypervariable region 1 (HVR1), the human contaminants can often outnumber the endogenous DNA, thus preventing a successful retrieval of Neandertal sequences. We have developed a novel PCR method, based on the use of blocking primers that preferentially bind to modern human contaminant DNA and block their amplification, and greatly improve the efficiency of Neandertal DNA retrieval. We tested the method in four El Sidrón Neandertal samples (two teeth and two bone fragments) with different contamination levels and taphonomic conditions, and we have been able to significantly increase the Neandertal yield from figures around 25.23% (5–69.6%) up to 90.18% (75.3–100%). 相似文献
105.
Jose Vicedo Antonio Ferrández 《Revue de synthèse / Centre international de synthèse》1999,120(4):687-688
Vie Scientifique
Symposium international Galileo 2001 Tenerife, February 19–23, 2001 相似文献106.
This paper discusses the relationship between early anarchism and republican/nationalist ideas. We will focus on the case of British‐based activists grouped around the journal Freedom and their engagement with Irish nationalism during the Age of the Empire. Freedom, founded in 1886, was the most important anarchist journal of the English‐speaking anarchist–communist networks at the time and was the main editorial reference for the worldwide community of anarchist activists, mostly exiled, who resided in London at that time. Extending current interdisciplinary literature on transnational anarchism, we argue that anarchist views of nations, while rejecting the novel notion of the nation‐state, were associated with anti‐colonial struggles and with republican anti‐monarchical and egalitarian notions. Based on primary sources, we discuss the intersections between these Britain‐based anarchists and anti‐colonial Irish radicals, by engaging both with their writings and their international networks of solidarity, thus exploring the complex intermingling of anarchism, anti‐colonialism, and republicanism. 相似文献
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108.
The value of strontium isotope analysis in identifying immigrants at numerous archaeological sites and regional areas has been demonstrated by several researchers, usually by comparing 87Sr/86Sr values of human tooth enamel and/or bone with the local strontium isotope signature determined by faunal and environmental samples. This paper examines the feasibility of using 87Sr/86Sr ratios to investigate residential mobility in the Nile Valley region, specifically at the New Kingdom period (∼1050–1400 BC) archaeological site of Tombos (ancient Nubia). Archaeological and textual information regarding this period indicates that immigrant Egyptians and local native Nubians were likely interacting at this site during a period of Egyptian colonial occupation. The results of this study suggest that non-local individuals may be distinguished from locals using 87Sr/86Sr values and that colonial agents in the Tombos population were probably both local native Nubians and immigrants. 相似文献
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110.
Antonio Paez 《Geographical analysis》2019,51(3):314-338
Residual spatial autocorrelation is a situation frequently encountered in regression analysis of spatial data. The statistical problems arising due to this phenomenon are well‐understood. Original developments in the field of statistical analysis of spatial data were meant to detect spatial pattern, in order to assess whether corrective measures were required. An early development was the use of residual autocorrelation as an exploratory tool to improve regression analysis of spatial data. In this note, we propose the use of spatial filtering and exploratory data analysis as a way to identify omitted but potentially relevant independent variables. We use an example of blood donation patterns in Toronto, Canada, to demonstrate the proposed approach. In particular, we show how an initial filter used to rectify autocorrelation problems can be progressively replaced by substantive variables. In the present case, the variables so retrieved reveal the impact of urban form, travel habits, and demographic and socio‐economic attributes on donation rates. The approach is particularly appealing for model formulations that do not easily accommodate positive spatial autocorrelation, but should be of interest as well for the case of continuous variables in linear regression. 相似文献