全文获取类型
收费全文 | 9613篇 |
免费 | 368篇 |
国内免费 | 3篇 |
专业分类
9984篇 |
出版年
2022年 | 72篇 |
2021年 | 102篇 |
2020年 | 116篇 |
2019年 | 166篇 |
2018年 | 254篇 |
2017年 | 234篇 |
2016年 | 244篇 |
2015年 | 180篇 |
2014年 | 203篇 |
2013年 | 897篇 |
2012年 | 367篇 |
2011年 | 386篇 |
2010年 | 214篇 |
2009年 | 228篇 |
2008年 | 321篇 |
2007年 | 303篇 |
2006年 | 262篇 |
2005年 | 227篇 |
2004年 | 242篇 |
2003年 | 221篇 |
2002年 | 209篇 |
2001年 | 282篇 |
2000年 | 282篇 |
1999年 | 196篇 |
1998年 | 97篇 |
1997年 | 87篇 |
1996年 | 80篇 |
1995年 | 69篇 |
1992年 | 155篇 |
1991年 | 145篇 |
1990年 | 160篇 |
1989年 | 141篇 |
1988年 | 126篇 |
1987年 | 118篇 |
1986年 | 138篇 |
1985年 | 134篇 |
1984年 | 116篇 |
1983年 | 100篇 |
1979年 | 110篇 |
1978年 | 81篇 |
1975年 | 71篇 |
1974年 | 98篇 |
1973年 | 104篇 |
1972年 | 82篇 |
1971年 | 73篇 |
1970年 | 85篇 |
1969年 | 76篇 |
1968年 | 110篇 |
1967年 | 87篇 |
1966年 | 99篇 |
排序方式: 共有9984条查询结果,搜索用时 15 毫秒
201.
IVAN W. MILLER ROBERT I. KABACOFF NATHAN B. EPSTEIN DUANE S. BISHOP GABOR I. KEITNER LAWRENCE M. BALDWIN H.I.J. van der SPUY 《Family process》1994,33(1):53-69
This article describes the development and validation of the McMaster Clinical Rating Scale (MCRS). The MCRS is a 7-item scale designed to be completed by a trained rater after completion of an in-depth interview of the family. We present data from four new studies and review previously published articles concerning the reliability, validity, and clinical utility of the MCRS. Adequate interrater reliability and rater stability were obtained. The MCRS was found to correlate significantly with the self-report Family Assessment Device and to discriminate between families in different phases of a depressive disorder. 相似文献
202.
Two studies were conducted to investigate the potential effects on workrelated behavior of one environmental variable: pleasant fragrances. In Study 1, participants performed a word construction task under low or high stress while in the presence or absence of pleasant fragrances. Performance was significantly enhanced by fragrance in both stress conditions. In addition, exposure to pleasant fragrances significantly increased performance on an additional task (decoding written messages) completed by participants following exposure to stress. In Study 2, both exposure to pleasant fragrances and receipt of a small gift increased performance on the same word construction task used in Study 1. In addition, fragrance and a gift increased participants' willingness to engage in both immediate and delayed helping. Together, the results of these studies offer support for the view that pleasant fragrances can influence work-related behavior, and that such effects may be mediated, at least in part, by increments in positive affect. 相似文献
203.
Recent legislative and regulatory developments have focused attention on older adults' capacity for involvement in health care decision-making. The Omnibus Budget Reconciliation Act of 1987 (OBRA 87) focused attention on the rights of nursing home residents to be involved in health care decision-making to the fullest extent possible. This article uses data from the 1987 National Medical Expenditure Survey (NMES) to examine rates of incapacity for health care decision-making among nursing home residents. Elements of the Oklahoma statute were used to operationalize decision-making incapacity: disability or disorder, difficulty in decision-making or communicating decisions, and functional disability. Fifty-three percent of nursing home residents had a combination of either physical or mental impairment and an impairment in either self-care or money management. The discussion focuses on the policy and practice implications of significant rates of incapacity among nursing home residents. 相似文献
204.
Ren van Woudenberg 《Ratio》1995,8(2):170-188
This paper is a contribution to the debate on epistemic foundationalism. Section I expounds and criticises Hans Albert's critical rationalist antifoundationalism position. Section I1 discusses Karl-Otto Apel's ‘transcendental pragmatic’ argument for ultimate epistemic foundations. Section III suggests how the latter argument can be restated so as to avoid ambiguity and yield a plausible case for epistemic foundationalism. 相似文献
205.
Progressive supranuclear palsy (PSP) is the epitome of a subcortical dementia process. Due to its relative rarity, there is only a small literature on the neuropsychological consequences of PSP. The findings to date demonstrate that PSP patients have dramatically slowed information processing and motor execution, rapid forgetting, problems in orienting attentional resources, and difficulty in planning and shifting conceptual sets. The pattern and severity of these deficits are unique to PSP and suggest that the study of PSP patients can provide a special insight into brain-behavior relations. 相似文献
206.
A methodology for the quantitative evaluation of observed workload was proposed. The model was designed to provide point estimations of observed workload at any time during the performance of a set of tasks. The model was also designed to provide information about the task-scheduling strategies used to complete a set of tasks. The proposed model was then tested with data from a full mission flight simulation. The model predictions correlated significantly with expert ratings of workload management made during the flight simulation. The model was also able to distinguish between low- and high-performing aircrews when performance was based on the number of errors made during flight simulations. 相似文献
207.
We quantified the ability of human subjects to discriminate the relative distance of two points from a slanted plane when viewing the projected velocities of this scene (orthographic projection). The relative distance from a plane (called relief) is a 3-D property that is invariant under linear (affine) transformations. As such, relief canin principle be extracted from the instantaneous projected velocity field; a metric representation, which requires the extraction of visual acceleration, is not required. The stimulus consisted of a slanted planeP (specified by three points) and two pointsQ 1 andQ 2 that are non-coplanar withP. This configuration of points oscillated rigidly around the vertical axis. We have measured thesystematic error andaccuracy with which human subjects estimate the relative distance of pointsQ 1 andQ 2 from planeP as a function of the slant ofP. The systematic error varies with slant: it is low for small slant values, reaches a maximum for medium slant values, and drops again for high slant values. The accuracy covaries with the systematic error and is thus high for small and large slant values and low for medium slant values. These results are successfully modeled by a simple relief-from-motion computation based on local estimates of projected velocities. The data are well predicted by assuming (1) a measurement error in velocity estimation that varies proportionally to velocity (Weber’s law) and (2) an eccentricity-dependent underestimation of velocity. 相似文献
208.
The purpose of this study was to determine the extent to which lobectomy affects ability to discriminate facial identity or facial expression. Fifteen right temporal, 15 left temporal, 5 right frontal, and 4 left frontal lobectomy patients, pair-matched for age, sex, and education to normal control subjects, participated in this study. Tasks included a Facial Identity Matching Task and a Facial Affect Matching task. The lobectomized patients as a whole were significantly impaired on both tasks (22% decrement in performance). The patients made twice as many errors resulting from perseveration of response-set of the first condition (identity or emotion matching) into the second condition. The site of lobectomy did not influence general performance on any one task or selective performance on any subset of affective categories. It was concluded that all four brain regions play a significant and equal role in face processing, and that circuits more specifically dedicated to visual face processing, which are responsible for hemispheric dominance affects and affect/identity dissociations, are probably located more posteriorly in the brain. Finally, it was concluded that perseveration of acquired habit may, under specific conditions, characterize temporal lobe dysfunction just as much as frontal lobe dysfunction. 相似文献
209.
210.
Peter A. van der Helm 《Psychological research》1994,56(4):224-236
Summary There is quite wide-spread agreement about the relevance of pattern Pragnanz (Koffka, 1935) with respect to the human interpretation of visual patterns. There is less agreement about whether pattern Pragnanz is based solely on pattern information (static) or also on the history of the perceiver (dynamic). In Van Leeuwen and Van den Hof (1991), experimental data concerning serial patterns are presented within the framework of the dynamic-network approach initiated by Buffart (1986, 1987). These experimental data are claimed to give evidence against the static-coding approach initiated by Leeuwenberg (1969, 1971). In the present paper, however, I show first that Buffart's theoretical basis is incorrect, and that in fact Leeuwenberg's static-coding approach is the basis for the dynamic-network approach. Second, I show that those experimental data rather give evidence in favor of the static-coding approach, by using those same data for a test of the most recent static-coding model (Van der Helm & Leeuwenberg, 1991; Van der Helm, Van Lier, & Leeuwenberg, 1992). Finally, I propose a reconciliation between the two approaches, in the sense that the dynamic-network model could be shaped in such a way that it yields a simulation, and maybe even an enrichment, of the static-coding model. 相似文献