全文获取类型
收费全文 | 6340篇 |
免费 | 242篇 |
出版年
2020年 | 78篇 |
2019年 | 143篇 |
2018年 | 179篇 |
2017年 | 203篇 |
2016年 | 191篇 |
2015年 | 162篇 |
2014年 | 149篇 |
2013年 | 1817篇 |
2012年 | 193篇 |
2011年 | 183篇 |
2010年 | 206篇 |
2009年 | 198篇 |
2008年 | 144篇 |
2007年 | 161篇 |
2006年 | 148篇 |
2005年 | 94篇 |
2004年 | 88篇 |
2003年 | 87篇 |
2002年 | 103篇 |
2001年 | 105篇 |
2000年 | 85篇 |
1999年 | 86篇 |
1998年 | 90篇 |
1997年 | 77篇 |
1996年 | 80篇 |
1995年 | 61篇 |
1994年 | 62篇 |
1993年 | 57篇 |
1992年 | 55篇 |
1991年 | 46篇 |
1990年 | 35篇 |
1989年 | 57篇 |
1988年 | 45篇 |
1987年 | 59篇 |
1986年 | 48篇 |
1985年 | 54篇 |
1984年 | 70篇 |
1983年 | 65篇 |
1982年 | 54篇 |
1981年 | 55篇 |
1980年 | 70篇 |
1979年 | 60篇 |
1978年 | 42篇 |
1977年 | 60篇 |
1976年 | 49篇 |
1975年 | 48篇 |
1974年 | 30篇 |
1972年 | 30篇 |
1971年 | 28篇 |
1969年 | 27篇 |
排序方式: 共有6582条查询结果,搜索用时 15 毫秒
1.
Evidence from several disciplines supports the proposition that following the Wisconsinan and an initial but brief moist phase of the Holocene, there was a gradual drying trend in the mid-continent Prairie Peninsula that peaked about 7000 years ago, a pattern that was not reversed until about 4000 years ago. Except for minor perturbations, conditions during the past four millennia have essentially been similar to those of the present. Studies in palynology and geomorphology have shown that the climatic regimes of the early/mid Post-glacial had a marked influence on both the biota and landscape erosional patterns, especially along the margins of the Prairie Peninsula. Measurable changes in the landscape and attendant biota show a time-transgressive pattern of drought related phenomena recorded palaeo-ecologically from west to east.Few studies of archaeological sites in the Prairie Peninsula have examined the evidence in and around the sites themselves for data reflecting local environmental dynamics. In fact, earlier models proposed for explaining the evolution of food-procuring systems in eastern North America virtually ignored potential changes in the natural environment. This paper examines data from two archaeological sites along the prairie-forest border in Missouri that contain long cultural sequences. Evidence is presented that pronounced changes in the natural environment occurred and that these biophysical variables are indeed critical for understanding the evolution of food-procuring societies in the American Midwest. 相似文献
2.
We analyze the response of municipalities to the occurrence of natural disasters in terms of spending behavior, use of upper-tier transfers and recovery, using balance sheet data of about 8,000 Italian municipalities for the period 2000–2015, and the universe of earthquakes events. We find evidence of increasing expenditure for about 12 years after the shocks, with asymmetric responses between earthquake-related and unconditional grants, and heterogeneous flypaper effects across the country. While in northern municipalities expenditure tends to regress to pre-earthquake levels, southern municipalities stick to higher expenditure levels when grants drop. This evidence is coupled with a faster recovery of private income and housing prices in northern municipalities. 相似文献
3.
4.
5.
6.
7.
Michael J. Watts 《对极》2010,41(Z1):10-26
Abstract: Antipode was launched into the firmament of the 1970s. We might reflect upon how well the journal and its contributors fully appreciated the historical gravity and weight of what was surrounding the project to create “a radical journal of geography”. What sort of radicalism was on offer? The language was “social relevance” from “a radical (Left) political viewpoint”. In writing to celebrate Antipode's birthday, this time in another, and similar, firmament there is still the need to confront the challenge of radicalism and its meanings. Whether we agree with Perry Anderson that the last vestiges of the 1960s have been finally swept away, that the “fluent vision” of the Right has no equivalent on the Left and that embedded liberalism is now as remote as “Arian bishops”, where do radical alternatives stand in relation to the fractured hegemony of neoliberalism? At the very least the need for alternatives is more pressing than ever. David Harvey has proposed rethinking the idea of “the right to the city”. But what other rights might we rethink? I reflect upon this question by returning to the 1960s and 1970s and Marxist debates over the law, and by thinking about the possibilities offered by this Polanyian moment. 相似文献
8.
9.
Michael A. Penman Author vitae 《Journal of Medieval History》2011,37(3):295-303
This paper examines the comparatively patchy evidence for the pastoral provision and personal faith of late medieval Scottish combatants below the rank of knight. By examining such sources as papal supplications, royal financial accounts, parliamentary rolls, chronicles, poetry and the cartularies of Scottish monastic houses and burgh collegiate churches, it is possible to identify elite and parish provision of churchmen serving the needs of Scottish troops as they mustered, trained and prepared for battle. In addition, this evidence also highlights a number of cults and relics popular with the social ranks of the ordinary Scottish soldiery, including those of SS Ninian, Leonard, Thomas Becket, Columba, the Blessed Virgin Mary and — often cast as the nemesis of Scottish troops — Cuthbert. However, this survey also points to some tensions between the spiritual interests of Scottish servicemen and their ruling elites. 相似文献
10.
This study explores the spatial structure of retailing in Milwaukee, Wisconsin, in the era before the introduction of the electric streetcar in 1890. It uses city directory listings to chart changes in the numbers and types of retail outlets, their degree of nucleation and the functional complexity of such nucleations. The evidence suggests the early appearance of non-central retailing, the rapid dispersal of high as well as low order goods to non-central sites and the early emergence initially of a three-level and then, by 1870, a four-level hierarchy of shopping clusters. The pattern of retail clustering varied with the class and ethnic character of neighbourhoods, and clusters gravitated toward major arterial routes even in the pre-mass transit ear. Urban retailing in the second half of the nineteenth century was neither randomly dispersed nor over-whelmingly concentrated in a single central retail district, but developed a spatial hierarchy that clearly anticipated modern patterns. 相似文献