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131.
From Monad to Man: The Concept of Progress in Evolutionary Biology. By Michael Ruse (Harvard University Press, 1997), x + 628 pp., $49.95 cloth.  相似文献   
132.
133.
Traditional notions that family life among slaves during the pre-plantation period in the non-Hispanic Caribbean was necessarily unstable are fading in light of new research. Although marriage among this segment of the population in Caguas, Cayey, San Germán, and Yauco--rural parishes in Puerto Rico--involved only a fraction of the overall number of marriages in these communities, the marriage of slaves was much more frequent than previously assumed. Family life among the eighteenth-century Puerto Rican slave population appears to have been quite stable, as shown by the reconstruction of birth intervals for both married and unmarried mothers. Married and unmarried mothers exhibited similar reproductive behavior. These results strongly suggest that a majority of the unmarried slave mothers lived in unions that were not institutionally recognized, but that were nevertheless stable, as indicated by the high percentage of their children born at intervals comparable to those of married mothers. If unmarried mothers were living in stable consensual unions, then our understanding of these slave family units during the colonial period must be reassessed not only for Puerto Rico but possibly for the rest of the Caribbean and Latin America.  相似文献   
134.
Cities across America look for management strategies useful for accomplishing their responsibilities and programs. While some cities include privatization strategies in their management portfolios, others do not, and the underlying reasons are not readily apparent. This study seeks to gain some insight into this disparity through several questions: Why do some cities use more privatization than others? Are privatization levels higher in fiscally healthy or fiscally stressed cities? Where are the cities that use privatization located? This study attributes municipal privatization levels in medium-sized cities, in part, to degree of wealth, fiscal stress, and location. The findings suggest that privatization levels are higher in wealthy, fiscally healthy, suburban cities.  相似文献   
135.
In the last two decades, many states established rail promotion programs in an effort to limit the contraction of their railroad networks. Now federal funds for rail projects are nearly exhausted, and states must decide whether to expand considerably their levels of internal funding for short line investments. Such a decision requires a careful articulation of policy goals, combined with sound cost-benefit techniques. Research shows, however, that states often fail to evaluate the full range of costs and benefits when considering rail investments. Instead, the economic development benefits of local rail service frequently are overstated, while the potential for rail investments to meet broader transportation planning needs is neglected. This paper evaluates the rationale behind state intervention in the rail industry, discusses the tendency of states to focus on economic development to the exclusion of other benefit categories, and presents summary results from an analysis of an investment project in North Carolina. The paper suggests that state funding for rail projects is more likely to be justified based on intermodal substitution benefits generated by local rail service, rather than the railroads' potential to increase jobs.  相似文献   
136.
D. A. SCOTT 《Archaeometry》1996,38(2):305-311
Examination of a Sican ceremonial tumi, dated to the Middle Sican, c. AD 850–1050, showed that it was made in a silver-copper alloy of approximate composition 93% silver, 6% copper. Many separate pieces are used in the construction, joined together by both mechanical methods and by solder. The principal figure has been made from 18 separate silver sheets, with 169 separate parts identified in the head-dress, totalling 187 design elements. Metallographic examination of a fragment of repoussé decorated sheet from the figure surmounting the tumi surprisingly showed that the silver-copper alloy has a cast morphology; this demonstrates that Sican metalsmiths were pre-casting silver-copper sheet into the dimensions required for making the tumi, rather than carrying out the expected process of making the idol from hammered silver-copper sheet, shaped by extensive cycles of working and annealing, thus contradicting the usual assumptions about the manufacture of sheet-metalwork made in such cases.  相似文献   
137.
Non-destructive X-ray fluorescence analyses induced by white synchrotron radiation (SYXRF) have been performed on a page of the Gutenberg Bible and 21 other different single leaves printed in the years 1470 to 1500. Absolute elemental areal densities for the papers and the inks are reported. The known high Cu and Pb content in Gutenberg's ink is confirmed. The elemental compositions of the other inks, if measurable by XRF at all, are in general very low, governed only by a few additional elements and found to be not distinctive for a known printer. This will render an identification of the printer or printing offices by ink composition analysis in the period after 1470 difficult.  相似文献   
138.
After over a century of archaeological research in the American Southwest, questions focusing on population aggregation and abandonment continue to preoccupy much of Pueblo archaeology. This article presents a historical overview of the present range of explanatory approaches to these two processes, with a primary focus on population aggregation in those regions occupied by historic and prehistoric Pueblo peoples. We stress the necessarily complementary nature of most of these explanations of residential abandonment and aggregation. Case studies from the northern Southwest illustrate the continuous nature of these processes across time and space. We suggest that additional explanatory potential will be gained by the use of well-defined theoretical units to frame our current approaches. We extend the use of the local community concept as a theoretical unit of organization that, along with explicit archaeological correlates, should help advance our research into population aggregation and abandonment in this and other regions of the world.  相似文献   
139.
We review evidence from human biology—paleopathological and isotopic paleodietary studies on ancient Maya skeletons—to assess the validity of ecological models of the Classic Maya collapse, in which elevated disease and deteriorating diet are commonly assumed. To be upheld, the health arguments of ecological models require that the Maya disease burden (1) was greater than that for many other societies and (2) increased over the span of occupation. The dietary argument requires (1) consistent change in diet from Preclassic and Early Classic Periods to the Terminal Classic and (2) increasing social divergence in diet. A correlation between diet and disease is necessary to link these arguments. Neither pathology nor isotopic data consistently support these criteria. Instead, it appears that local environmental and political factors created diversity in both disease burden and diet. In view of the human biological data, we are skeptical of ecological models as generalized explanations for the abandonment of Classic Maya sites in the southern lowlands.  相似文献   
140.
The Tilligerry Peninsula on the central NSW coast supports a significant Koala population. By 1992 residential and mining developments had reduced the identified Koala habitat on this peninsula to less than half of what was apparent in 1954. A major part of the habitat loss was caused by mining for silica and heavy mineral sands in the corridors connecting the forests of the peninsula to other areas of Koala habitat. The degree of habitat loss in three types of land use over four periods between 1954 and 1992 is examined.  相似文献   
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