全文获取类型
收费全文 | 8688篇 |
免费 | 313篇 |
专业分类
9001篇 |
出版年
2020年 | 117篇 |
2019年 | 162篇 |
2018年 | 175篇 |
2017年 | 217篇 |
2016年 | 293篇 |
2015年 | 187篇 |
2014年 | 170篇 |
2013年 | 2228篇 |
2012年 | 214篇 |
2011年 | 262篇 |
2010年 | 240篇 |
2009年 | 209篇 |
2008年 | 198篇 |
2007年 | 172篇 |
2006年 | 164篇 |
2005年 | 114篇 |
2004年 | 114篇 |
2003年 | 105篇 |
2002年 | 114篇 |
2001年 | 126篇 |
2000年 | 137篇 |
1999年 | 172篇 |
1998年 | 114篇 |
1997年 | 77篇 |
1996年 | 87篇 |
1995年 | 94篇 |
1994年 | 91篇 |
1993年 | 94篇 |
1992年 | 96篇 |
1991年 | 75篇 |
1990年 | 75篇 |
1989年 | 78篇 |
1988年 | 85篇 |
1987年 | 93篇 |
1986年 | 86篇 |
1985年 | 124篇 |
1984年 | 121篇 |
1983年 | 129篇 |
1982年 | 100篇 |
1981年 | 104篇 |
1980年 | 109篇 |
1979年 | 102篇 |
1978年 | 95篇 |
1977年 | 108篇 |
1976年 | 86篇 |
1975年 | 96篇 |
1974年 | 83篇 |
1973年 | 79篇 |
1972年 | 62篇 |
1971年 | 65篇 |
排序方式: 共有9001条查询结果,搜索用时 15 毫秒
71.
ABSTRACT This paper develops a model of regional financial markets which can encompass different degrees of spatial financial integration. The behavior of the system is analyzed under alternative assumptions about the time frame of analysis and the extent of the flexibility of interest rates. It is argued that links may exist between regional real and financial sectors even in the short run and that such links must, through the regional balance of payments, exist in the long run, even where there is perfect financial spatial integration. It is observed that these relationships have generally been ignored by regional economic model builders. 相似文献
72.
73.
74.
75.
76.
77.
78.
79.
80.
G. DE G. SIEVEKING P. BUSH J. FERGUSON P. T. CRADDOCK M. J. HUGHES M. R. COWELL 《Archaeometry》1972,14(2):151-176
This paper is a statistical and geological study of the results of analysis of flint from British and West European flint mines, carried out by emission and atomic absorption spectroscopy. Groups of flint specimens were studied from each geographically separate flint mining area. Flints were analysed for a group of easily measured trace elements shown by previous work to be generally present. The ratios between the trace elements form a consistent pattern for each flint mine and statistically valid differences of pattern can be recognized between different flint mines. A geological investigation shows that the measured trace elements may be derived from clay minerals and explains geographical and statistical variation in the composition of flint in terms of its mode of origin in the chalk. An advanced statistical technique allows individual flint specimens of unknown origin to be attributed by their composition to one or other of the identified flint sources. The archaeological implications of this study are discussed. 相似文献