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991.
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Conventional wisdom provides an increasingly strong endorsement of far-reaching decentralization and delegation of authority to bureaucratic agents as the most likely mechanisms to attain such central environmental policy goals as pollution prevention, cross-media regulatory integration, and development of reliable measures of environmental outcomes. Canada would appear an unusually fertile context for such Innovation, given its far-reaching deference to individual provinces and their environment ministries in environmental policy. Comparative analysis of select sub national governments in Canada and the United States suggests that the states in general are far ahead of their provincial counterparts in most of these areas of innovation. Despite all the opprobrium heaped on the American environmental policy system, a combination of federal policy tools and state policy entrepreneur ship appear to contribute directly to this innovation in some states and are almost completely absent in the Canadian system. These findings suggest a need for careful study of the mix of intergovernmental policy tools and principal-agent relations most likely to realize desired environmental policy goals.  相似文献   
994.
Employing theories and methods of agenda-setting analysis, this article explains the rapid rise of physician-assisted suicide (PAS) on the national political agenda based on its status as a morality policy. PAS reached the mass agenda before the professional agenda, probably because PAS is an outgrowth of previous right-to-die policies and Dr. Jack Kevorkian's assisted suicides provided major focusing events. As in other morality policies, competing groups fight for the last word, but PAS has been blocked on most governmental agendas because its image and media tone has been mostly negative and public opinion is divided. Groups in a few generally liberal states have tried to enact policy through referenda when legislators failed to address the issue. We speculate that competing interest groups will become more active and that state courts will become a venue of choice in the future.  相似文献   
995.
Florisbad, an open-air spring site with 7 m of strata, has yielded the type assemblage of Middle Stone Age (MSA) fauna, the cranium of an archaic hominid in 1932 and an extensive sequence of MSA artefacts in the 1980s. The cultural assemblages include an early MSA dated broadly to 279,000±47,000 years, a highly retouched form of MSA at 157,000±21,000 years and a minimally retouched, expedient MSA assemblage from a series of occupation horizons at 121,000±6000 years. The latter represents multiple brief visits to a hunting and butchery site on the edge of an active spring pool, where periodic sedimentation gently buried occupation debris in a near-pristine context. Periods of lower spring discharge are represented by organic horizons as swampy vegetation encroached on the springs, while periods of higher spring discharge created pools. Overall the spring sequence indicates low-energy subaqueous environments similar to lakes, ponds or backwater sites. The sequence is characterized by fine sands, silts and clays responsible for the good archaeological preservation.  相似文献   
996.
This paper examines the concept of metropolitan dominance as measured by the concentration of corporate activity in large urban centres in the Canadian urban system. Specifically, it explores the extent of corporate concentration in various sectors of the economy; isolates those urban centres in which that concentration occurs; and identifies the extent and location of international penetration of the Canadian economy.
Dans cette étude, nous examinons le concept de l'importance des métropoles en fonction de la concentration des diverses entreprises dans le systeme urbain du Canada. Plus spécifiquement, nous examinons le degré de cette concentration dans divers secteurs économiques; nous isolons les centres urbain ou a lieu cette concentration; nous identifions l'étendue et les points de pénetration internationale dans l'économie du Canada.  相似文献   
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Recovered and amplified ancient DNA (aDNA), from a historically documented 19th century Upper Canadian pioneer cemetery produced genotypes that were used to infer a past societal kinship system. While the results from multiplex short tandem repeat (STR) amplifications showed an unreliable polymerase chain reaction (PCR) product, a single locus HUMTH01 analysis yielded reproducible data and an allelic frequency pattern not statistically different from modern populations. Mitochondrial (mt) DNA HVR II data showed that a combined cemetery database exhibited reduced haplotype diversity indicators, as well as clusters of probable maternally related burials. The chronological persistence and replacement of mtDNA clusters approximately every two generations suggests a patrilineal/patrilocal kinship structure from a virilocal burial program for the Harmony Road cemetery. Through the integration of the aDNA analysis with archaeological material culture, historic records, and other ethnohistoric sources of information, this conclusion is supported. In this study persisting patrilineally inherited surnames act as a surrogate for aDNA Y‐chromosome haplotype analysis. These results suggest that aDNA applications on aggregate skeletal collections where sparse, or no ethnological or historical documentation exists, may result in incorrect population history inferences if the presence of a kinship interment bias is not considered. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
1000.
G. R. OSINSKI 《Geofluids》2005,5(3):202-220
Combined field studies, optical and scanning electron microscopy, and electron microprobe studies of impactites from the Ries impact structure, Germany, have allowed a clearer picture of the hydrothermal system associated with the Ries impact event to be made. Hydrothermal alteration is concentrated within impact‐generated suevites in the interior of the crater (crater suevites) and around the periphery (surficial suevites), with minor alteration in the overlying sedimentary crater‐fill deposits. The major heat source for the Ries hydrothermal system was the suevite units themselves. Hydrothermal alteration of crater‐fill suevites is pervasive in nature and comprises several distinct alteration phases that vary with depth. An early phase of K‐metasomatism accompanied by minor albitization of crystalline basement clasts and minor chloritization, was followed by pervasive intermediate argillic alteration (predominantly montmorillonite, saponite, and illite) and zeolitization (predominantly analcite, erionite, and clinoptilolite). Hydrothermal fluids were typically weakly alkaline during the main stage of alteration. In contrast to the crater‐fill suevites, alteration within surficial suevites was typically restricted to montmorillonite and phillipsite deposition within cavities and fractures. The pervasive nature of the alteration within the crater‐fill suevites was likely due to the presence of an overlying crater lake; whereas alteration within surficial suevites typically occurred under undersaturated conditions with the main source of water being from precipitation. There are exceptional outcrops of more pervasively altered surficial suevites, which can be explained as locations where water pooled for longer periods of time. Hydrothermal fluids were likely a combination of meteoric waters that percolated down from the overlying crater lake and groundwaters that flowed in from the surrounding country rocks.  相似文献   
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