全文获取类型
收费全文 | 5461篇 |
免费 | 47篇 |
国内免费 | 1篇 |
出版年
2020年 | 21篇 |
2019年 | 20篇 |
2018年 | 133篇 |
2017年 | 116篇 |
2016年 | 218篇 |
2015年 | 117篇 |
2014年 | 59篇 |
2013年 | 152篇 |
2012年 | 299篇 |
2011年 | 293篇 |
2010年 | 44篇 |
2009年 | 62篇 |
2008年 | 82篇 |
2007年 | 89篇 |
2006年 | 90篇 |
2005年 | 1353篇 |
2004年 | 691篇 |
2003年 | 488篇 |
2002年 | 181篇 |
2001年 | 39篇 |
2000年 | 19篇 |
1999年 | 42篇 |
1998年 | 19篇 |
1996年 | 17篇 |
1995年 | 14篇 |
1994年 | 17篇 |
1992年 | 36篇 |
1991年 | 47篇 |
1990年 | 66篇 |
1989年 | 51篇 |
1988年 | 32篇 |
1987年 | 45篇 |
1986年 | 40篇 |
1985年 | 36篇 |
1984年 | 34篇 |
1983年 | 25篇 |
1982年 | 15篇 |
1979年 | 37篇 |
1978年 | 20篇 |
1976年 | 13篇 |
1975年 | 35篇 |
1974年 | 35篇 |
1973年 | 36篇 |
1972年 | 27篇 |
1971年 | 26篇 |
1970年 | 18篇 |
1969年 | 19篇 |
1968年 | 18篇 |
1967年 | 18篇 |
1966年 | 16篇 |
排序方式: 共有5509条查询结果,搜索用时 15 毫秒
51.
T Krause W P Pankau A Wagner J L?ssner 《Psychiatrie, Neurologie, und medizinische Psychologie》1984,36(9):545-550
By 48 patients with Wilson's disease the brainstem acoustic evoked potentials were stated. There were 35 pathological findings (73%), 13 were normal (27%). The waves, determined by the middle and upper brainstem (Pons and Mesencephalon) showed most of all pathological changes. Those patients with forms of Wilson's disease called Pseudoskelerose and Pseudoparkinson showed the most pathological findings. But one could watch these findings by about 30% of patients in preclinical stage. This method can possibly be used for early detection of disorders of brainstem functions and in the same way it can be used for control of treatment by patients in preclinical stage. 相似文献
52.
Neil Tennant 《Studia Logica》1984,43(1-2):181-200
This paper treats entailment as a subrelation of classical consequence and deducibility. Working with a Gentzen set-sequent system, we define an entailment as a substitution instance of a valid sequent all of whose premisses and conclusions are necessary for its classical validity. We also define a sequent Proof as one in which there are no applications of cut or dilution. The main result is that the entailments are exactly the Provable sequents. There are several important corollaries. Every unsatisfiable set is Provably inconsistent. Every logical consequence of a satisfiable set is Provable therefrom. Thus our system is adequate for ordinary mathematical practice. Moreover, transitivity of Proof fails upon accumulation of Proofs only when the newly combined premisses are inconsistent anyway, or the conclusion is a logical truth. In either case Proofs that show this can be effectively determined from the Proofs given. Thus transitivity fails where it least matters — arguably, where it ought to fail! We show also that entailments hold by virtue of logical form insufficient either to render the premisses inconsistent or to render the conclusion logically true. The Lewis paradoxes are not Provable. Our system is distinct from Anderson and Belnap's system of first degree entailments, and Johansson's minimal logic. Although the Curry set paradox is still Provable within naive set theory, our system offers the prospect of a more sensitive paraconsistent reconstruction of mathematics. It may also find applications within the logic of knowledge and belief. 相似文献
53.
54.
Neil H. Timm 《Psychometrika》1970,35(4):417-437
Employing simulated data, several methods for estimating correlation and variance-covariance matrices are studied for observations missing at random from data matrices. The effect of sample size, number of variables, percent of missing data and average intercorrelations of variables are examined for several proposed methods.The author is indebted to Professors Leonard A. Marascuilo, Gus W. Haggstrom, especially Henry F. Kaiser for their invaluable suggestions throughout this work. Appreciation is also extended to the Computer Center facility of the University of California at Berkeley for the use of computer time to complete the necessary computations. 相似文献
55.
56.
57.
58.
59.
60.
Tenacious goal pursuit and flexible goal adjustment: explication and age-related analysis of assimilative and accommodative strategies of coping 总被引:6,自引:0,他引:6
Crises and critical life transitions activate 2 distinct but complementary modes of coping, (a) transforming developmental circumstances in accordance with personal preferences (assimilative tendency) and (b) adjusting personal preferences to situational constraints (accommodative tendency). Assimilative and accommodative tendencies were measured by a questionnaire comprising 2 independent scales (Tenacious Goal Pursuit and Flexible Goal Adjustment). Both scales predict high life satisfaction and low depression and are positively related to generalized internal control beliefs. The scales evinced an opposite relation to age: Cross-sectional analyses on a sample of 890 Ss in the age range from 34 to 63 years revealed a gradual shift from an assimilative to an accommodative mode of coping. Implications for theories of depression and successful aging are discussed. 相似文献