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41.
Coprolites attributable to humans, dated from the Pleistocene–Holocene transition, obtained from the archaeological site Cerro Casa de Piedra, Santa Cruz Province, were examined for parasites. The feces were processed by rehydration and spontaneous sedimentation using conventional parasitic procedures. Helminthic eggs recovered were identified as Trichuris sp., Calodium sp., other capilariids, and ancylostomid (Nematoda), probably Hymenolepis sp. and anoplocephalid (Cestoda); one oocyst attributable to Eimeria macusaniensis (Apicomplexa) was also found. According to the life-cycles and specificity of the parasites found, it is possible to suggest that some species (i.e., E. macusaniensis and Calodium sp.) represent parasites in transit or pseudoparasitism. Paleoparasitological results revealed the existence of an intensive relationship between parasites and humans in the Pleistocene–Holocene transition in Patagonia. Evidence suggests an early association among parasites, rock shelters and hunter–gatherers in the region. It is also postulated that the ancient lifestyles associated with caves and rock shelters were conductive to illness.  相似文献   
42.
Data of high resolution for reconstructions of archaeological site formation processes can be obtained only by the use of precise excavation methods and comprehensive recovery techniques using fine-mesh water screening, followed by meticulous sorting and quantitative studies of all the small organic components from the screens. These methods are generally used at human occupation sites, but are not often employed at paleontological or mixed human-carnivore sites. At the site of Bois Roche, an Upper Pleistocene hyena den, we have used these meticulous recovery techniques in combination with absolute dating, geoarchaeological observations, taphonomic analyses, studies of microvertebrates and pollen analysis. Correlation of the site environmental data from pollen and microvertebrate assemblages with the vegetation record of a deep-sea core taken in the Bay of Biscay have allowed us to constrain the ages provided by ESR dating of bovid teeth and to reconstruct the physical environment of the site with a degree of confidence rarely achieved by the use of fossil remains from archaeological sites alone.  相似文献   
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冯娟  罗静 《人文地理》2013,28(5):81-86
我国进入快速城市化发展时期以来,在城市化和工业化的推动下,各类村镇主体的空间行为能力逐步增强,在其追求自身利益最大化的过程中,往往出现不理性的空间行为,在农村地区引发出诸多的空间问题。本文以各类村镇主体(农村居民、企业、农村基层自治组织、地方政府)的空间行为为研究对象,运用博弈理论深入分析各类不良空间行为产生的根源,有针对性地提出相关公共政策建议,以期改变其博弈规则,从而有效引导和规范各类村镇主体的空间行为,优化村镇空间。  相似文献   
45.
苏晓智  白娟 《人文地理》2013,28(4):58-63
在当代世界各国的城市化进程中,城市的更新改造和发展以及相关问题和矛盾的解决都是要面临的重要课题。示范城市运动是美国大规模城市更新运动的重要阶段,也是轰轰烈烈的"伟大社会"改革中后期重要的战略转移。本文选取该项运动为研究主题,回顾了其发生背景、发展过程,分析了其正反两方面的经验,以期为中国在进入改革开放关键时期构建和谐社会进程中更好地解决城市问题提供一个有价值的参照。  相似文献   
46.
上海大都市区物联网产业集聚与空间演化   总被引:4,自引:0,他引:4  
新兴技术产业的空间集聚与扩散对大都市区的空间结构有直接的影响,厘清新兴技术产业的空间分布和区位选择规律对新兴产业集群培育和大都市区空间结构调整都具有重要的政策意义。本文分析了上海市物联网企业的空间分布和集聚特征,结果发现初创期物联网企业在郊区集聚,随后向郊区其他区域扩散,并呈现出从单极向多极集聚转变的空间演化进程。通过构建负二项回归探究上海物联网企业的区位选择因素,结果表明制度因素和企业集聚效应对企业区位选择有重要影响。在产业发展初创期,企业区位选择受政府管制和市场机制双重影响,其中制度因素发挥了关键作用;而在随后的兴起期,产业集聚效应对新企业的入驻具有强大的吸引力。  相似文献   
47.
江金波  高娟 《人文地理》2011,26(4):29-34
伴随改革开放30年进程,中国旅游产业不断走向内生驱动、创新发展之路。其在制度体制机制创新、理论创新等理论研究领域以及区域旅游创新、旅游企业创新等实践研究领域取得了初步成绩,但距离西方同类研究仍有较大差距。本文采取文献统计及文献分析法进行研究,揭示其基本特点,对中国旅游的创新研究主要领域进行文献研究综述,总结其研究的增长规律,立足于旅游产业创新研究的国际趋势和中国实际需要,最后对中国旅游的创新研究主要领域进行了展望。  相似文献   
48.
The modern project of rural development has been seen as one of increasing incorporation, control and rationalization of territory by the state. Evidence from the formulation of the Colombian land reform policy of 1961 gives more nuance to this general conceptualization. Those places where the state intervened through large‐scale resettlement programmes conceived within the framework of Cold War development are the same places where war and the drug economy — the most serious threats to the state itself — took root and grew. This article examines this contradiction. It interrogates the idea of modern development as a project that necessarily brings subjects and territories into the realm of state control. It also attempts to provide a counterweight to arguments about the territorialization of the war in Colombia being the outcome of state inaction and lack of development.  相似文献   
49.
El Mirón is a large cave in the Cantabrian Cordillera of northern Spain that presents a long archaeostratigraphic sequence radiocarbon-dated by over 60 assays to between 41,000 and 2000 BP. The sediments, collected from four areas within the cave and sieved-washed with fine wire meshes, contain microvertebrate remains of fish, frogs, lizards, birds and mammals, of which the latter are most abundant. Preliminary taphonomic analysis suggests that the microvertebrates were naturally collected by owls and (less) small carnivores. Small mammal assemblages are useful for palaeoenvironmental reconstruction because they are linked to particular habitats and are sensitive to environmental changes. The small mammals from El Mirón are ideal for this because sample sizes are large, bone preservation is good, and the stratigraphic sequence is long. In this paper we reconstruct the late Quaternary environments in the Cantabrian region of Spain using small-mammal assemblages from El Mirón Cave. On the basis of the ecologic adaptations of this suite of fauna, the majority still extant, we have identified seven habitat types, which are plotted through time. The evolution of the small mammal assemblages at El Mirón reveals seven major climatic shifts that correspond closely to the climatic changes recognized in the Iberian Peninsula during the last 41 kyr.  相似文献   
50.
古代建筑油饰彩绘传统工艺的科学化研究   总被引:2,自引:0,他引:2  
为了获得传统建筑彩绘工艺过程中的相关科学信息,以传统彩绘工艺过程为基础,利用光学显微镜、电子扫描显微镜、红外光谱、紫外可见光谱、动态粘弹谱、冷冻干燥、化学发光、视频接触角等手段对相关物料在传统工艺操作下的相互作用进行了系统研究.研究主要集中在揭示用于地仗制作物料的功能及其原理.研究结果表明:传统工艺蕴涵着深刻的科学内涵.用于彩绘的地仗是一个典型的复合材料,这种复合材料优越的性能来自于各物质间显著的协同作用.每种物料在其中的作用均可以利用现代科学理念给予阐释.这些理念包括聚合反应、高分子薄膜的固化作用、应力分散、网络结构以及物料相容性等.这些研究结果不仅对传统工艺的理解具有重要的意义,而且对于传统彩绘修复乃至当今复合材料研究也具有重要价值.  相似文献   
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