全文获取类型
收费全文 | 40425篇 |
免费 | 1651篇 |
国内免费 | 9篇 |
专业分类
42085篇 |
出版年
2020年 | 426篇 |
2019年 | 547篇 |
2018年 | 696篇 |
2017年 | 784篇 |
2016年 | 797篇 |
2015年 | 567篇 |
2014年 | 724篇 |
2013年 | 3238篇 |
2012年 | 1263篇 |
2011年 | 1329篇 |
2010年 | 827篇 |
2009年 | 824篇 |
2008年 | 1184篇 |
2007年 | 1150篇 |
2006年 | 1085篇 |
2005年 | 974篇 |
2004年 | 976篇 |
2003年 | 871篇 |
2002年 | 943篇 |
2001年 | 1109篇 |
2000年 | 1018篇 |
1999年 | 830篇 |
1998年 | 501篇 |
1997年 | 430篇 |
1995年 | 412篇 |
1992年 | 650篇 |
1991年 | 637篇 |
1990年 | 616篇 |
1989年 | 620篇 |
1988年 | 592篇 |
1987年 | 563篇 |
1986年 | 587篇 |
1985年 | 647篇 |
1984年 | 542篇 |
1983年 | 546篇 |
1982年 | 453篇 |
1981年 | 459篇 |
1979年 | 635篇 |
1978年 | 494篇 |
1977年 | 420篇 |
1976年 | 448篇 |
1975年 | 516篇 |
1974年 | 568篇 |
1973年 | 565篇 |
1972年 | 458篇 |
1971年 | 418篇 |
1969年 | 459篇 |
1968年 | 532篇 |
1967年 | 453篇 |
1966年 | 457篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
151.
Scopolamine interactions with D1 and D2 antagonists on radial-arm maze performance in rats 总被引:1,自引:0,他引:1
E D Levin 《Behavioral and neural biology》1988,50(2):240-245
Recent evidence indicates that acetylcholine and dopamine play complementary roles in cognitive as well as motor functions. In our previous study, the dopamine receptor blocker, haloperidol, was found to attenuate the radial-arm maze choice accuracy deficit caused by the muscarinic acetylcholine receptor blocker, scopolamine. Haloperidol has activity in blocking both D1 and D2 dopamine receptor subtypes. The current study was conducted to determine whether this dopamine-acetylcholine interaction specifically involved D1 or D2 dopamine receptors. The D1 antagonist, SCH 23390, and the D2 antagonist, raclopride, were administered with a dose of scopolamine which caused choice accuracy deficits in the radial-arm maze. The scopolamine-induced deficit was reversed by SCH 23390, the D1 antagonist, indicating that D1 blockade alone is sufficient to reverse the amnestic effects of muscarinic blockade. There was no indication in this study that the D2 blocker, raclopride, had a similar effect. However, this does not mean that such an effect may not be present at other doses of raclopride or with other D2 antagonists. The present finding that D1 blockade counteracts scopolamine-induced cognitive dysfunction not only furthers the understanding of dopamine-acetylcholine relationships in cognitive function, it also suggests a promising direction for the development of treatments for cognitive dysfunction due to cholinergic loss. 相似文献
152.
Summary The interactive-activation model postulates (a) that activation at the letter level leads automatically to activation at the word level, (b) that the word-superiority effect reflects reactivation of letters by the word they spell, and (c) that subjects identify words on the basis of information obtained from separate letter-position channels. In the first two experiments, we showed words in upper, lower, or mixed case: the word-superiority effect was reduced when words were presented in mixed-case letters, presumably because extra-letter information is lost with mixed-case presentation; i.e., postulate (c) is wrong. The third experiment showed that when the letters of a word are rotated 180° subjects can identify the letters without producing a word-superiority effect; i.e., one of postulates (a) and (b) is wrong. In Experiments 4 and 5, we trained subjects to name words presented in inverted letters; training was more effective when subjects could exploit bigram information in addition to letter-channel information; i.e., reading inverted text is based on extra-letter-feature information, not on a general skill in rotating letters. Taken together, our data deny three of the interactive-activation model's major postulates. We offer some suggestions for future versions of the model.
Electronic mail: Userid: MEWHORTD; Nodeid: QUCDN; Domain: BITNET 相似文献
153.
154.
James B. Wade Ph.D. Robert P. Hart Ph.D. Donald F. Kirby M.D. Peter R. Mills M.D. 《Group》1988,12(3):172-178
This study evaluated the efficacy of the Garren-Edwards Behavior Modification Program, which uses the Garren-Edwards Gastric Bubble as an adjunct to treatment. Group therapy sessions were conducted with 23 morbidly obese subjects for 6 months on a biweekly basis. Each therapy session used a five-stage problem-solving sequence designed to facilitate adaptive behavioral alternatives. In evaluating weight change, a multivariate analysis of variance was conducted along with two preplanned orthogonal comparisons. Patients lost significant amounts of weight between initial to 3-month (p<.0001) and 3- to 6-month intervals (p<0001). A similar treatment effect was noted in an additional sample of 24 morbidly obese subjects following 3 months of treatment (p<0005). The findings support the value of longer goal-oriented programs in promoting continued weight loss. Implications for treatment process and therapist interventions prompted by this new format are discussed. 相似文献
155.
Multiattribute analysis depends on measurement of values and weights. Unless these measures reflect the decision maker's true values and weights, the multiattribute formula may put a less-preferred alternative in first place. To avoid such disordinality requires stringent measurement conditions: First, the values and weights must be on linear (equal interval) or ratio (known zero) scales. Second, these scales must satisfy a condition of common unit across disparate attribute dimensions. Most methods of range adjustment beg both of these measurement questions. Functional measurement theory can solve both problems and so can be useful in multiattribute analysis. Past work has established the operation of a general cognitive algebra as an empirical reality. The averaging model, in particular, makes possible the definition and estimation of weights and values as distinct psychological parameters. It can also solve the problem of common unit. Cognitive algebra thus provides a grounded theoretical foundation on which to develop self-estimation methodology, in which decision makers provide direct estimates of their values and weights. The logic is straightforward. Functional measurement can analyze global judgments to obtain validated psychological scales. These scales may then be used as validational criteria for the self-estimates. Procedures to eliminate biases in the self-estimates can thus be tested and refined in well-learned multiattribute tasks, such as judgments of meals, in which global judgments are trustworthy. Once developed, such self-estimation procedures may be used with some confidence for general multiattribute analysis. A number of studies from 20-odd years of work on the theory of information integration are summarized to show good, although not unmixed promise for self-estimation. 相似文献
156.
J L Gariépy K E Hood R B Cairns 《Journal of comparative psychology (Washington, D.C. : 1983)》1988,102(4):392-399
This research was designed to investigate development and behavioral mediation in lines of ICR mice that have been selectively bred for aggressive behavior. General behavioral reactivity and behavioral immobility have been implicated as potential mediators by prior analyses of preattack interactions. To evaluate the separate roles of these dispositions, the emergence of attacks in genetically selected lines was tracked for 11 years by three levels of analysis: over successive generations, over development, and over dyadic interactions. Convergent outcomes were observed in all three levels with respect to two findings: (a) Robust line differences were obtained in attack behaviors, and (b) strong associations were found between line differences in attacks and line differences in behavioral immobility. Conversely, all three levels of analysis indicated a weak and inconsistent association between line differences in attacks and measures of social and nonsocial reactivity. 相似文献
157.
U W Huck R D Lisk E J Parente 《Journal of comparative psychology (Washington, D.C. : 1983)》1988,102(4):388-391
After 12-15 ejaculatory series, each consisting of several short intromissions (2- to 3-s vaginal penetration) and an ejaculation, male golden hamsters adopt an altered copulatory pattern consisting of long intromissions (5- to 25-s penetration with intravaginal thrusting). Receptivity declines and the tendency for the female to attack the male increases at about the time of this shift in copulatory pattern. Because the mean interintromission interval (III) between short intromissions is about 8 s compared to 100 s between long intromissions, it is possible that females detect this difference and adjust their mating accordingly. When the III between short intromissions from a rested male was experimentally increased to 100 s by use of a halter and lead device, the duration of lordosis was significantly less than that displayed by females paired with control males (8-s III) and virtually the same as that displayed by females paired with males that produced only long intromissions. This suggests that the female uses the temporal patterning of intravaginal stimulation as one criterion for terminating mating with a particular male. 相似文献
158.
Marianne Kastrup MD Inge Kemp Genefke MD Inge Lunde MD JØrgen Ortmann MD 《Contemporary Family Therapy》1988,10(4):280-287
This paper describes approaches taken at the International Rehabilitation and Research Centre in Copenhagen to helping torture victims and their families cope with the exposure to and aftermath of torture. 相似文献
159.
The purpose of this special issue of theJournal of Business and Psychology is to provide a review and update of several key types of non-traditional employment tests. Non-traditional employment tests can be divided into two categories. One category consists ofbiological/physiological tests. The second category consists ofnarrow-based personality tests. A framework for thinking about non-traditional employment tests is provided. 相似文献
160.
James E. McClellan Jr. 《Studies in East European Thought》1988,35(1):39-56
A philosophical movement, correctly called logical pragmatism, is growing up around the philosophy of W. V. O. Quine, Soviet scholars follow this development with clear and well-grounded understanding of the origins and tenets of the system. This essay continues the dialogue between contemporary Marxism-Leninism and logical pragmatism recommended by Soviet scholars.A Russian translation of this article is being published inFilosofskie nauki (Moscow). 相似文献