首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2807篇
  免费   156篇
  2963篇
  2023年   19篇
  2022年   13篇
  2021年   37篇
  2020年   73篇
  2019年   73篇
  2018年   94篇
  2017年   85篇
  2016年   99篇
  2015年   79篇
  2014年   84篇
  2013年   304篇
  2012年   152篇
  2011年   138篇
  2010年   86篇
  2009年   67篇
  2008年   126篇
  2007年   156篇
  2006年   119篇
  2005年   108篇
  2004年   102篇
  2003年   100篇
  2002年   88篇
  2001年   38篇
  2000年   41篇
  1999年   39篇
  1998年   34篇
  1997年   33篇
  1996年   32篇
  1995年   33篇
  1994年   33篇
  1993年   33篇
  1992年   31篇
  1991年   25篇
  1990年   26篇
  1989年   25篇
  1988年   22篇
  1987年   21篇
  1986年   24篇
  1985年   20篇
  1984年   18篇
  1983年   19篇
  1982年   34篇
  1981年   24篇
  1980年   15篇
  1979年   21篇
  1978年   16篇
  1977年   14篇
  1976年   19篇
  1975年   12篇
  1974年   18篇
排序方式: 共有2963条查询结果,搜索用时 0 毫秒
801.
802.
An item factor analysis of the 45 items of the Work Values Inventory (WVI) for 445 physically disabled clients produced six second-order dimensions: Stimulating Work, Interpersonal Satisfaction, Economic Security, Responsible Autonomy, Comfortable Existence, and Esthetic Concerns. These second-order factors provide a summary of clients' work motivation at a higher level of generality that is consistent with the WVI primary structure. The six factors are virtually independent of age, education, and intelligence and can be hand-scored by a simple procedure.  相似文献   
803.
The present study tested three assumptions often made by smoking prevention researchers and practitioners regarding the nature and causes of smoking prevalence estimates. Specifically, it is often assumed that (a) adolescent prevalence estimates of all levels of smoking are inflated, (b) youths at different stages of smoking onset all overestimate smoking prevalence, and (c) the predictors of these estimates are the same for youths at different stages of smoking onset. Measures of smoking behavior based on self-reports using a bogus pipeline procedure, estimates of cigarette smoking prevalence (trying behavior and weekly use), and reports of smoking in significant others were obtained by the same youths when they were in eighth and ninth grades. Results indicated that, taken over all youths, estimates of trying cigarettes were accurate, whereas estimates of weekly use were inflated. When responders were defined by their stage of smoking onset, either as a nonsmoker, trier, or regular smoker, analyses revealed that triers were accurate regarding prevalence estimates of trying, whereas non-smokers made gross underestimations and regular smokers made overestimations of trying. All groups of youths overestimated prevalence of weekly smoking. Analyses of variance revealed that both youths' smoking status and interpersonal smoking environment additively predicted prevalence estimates, and estimates of smoking prevalence were relatively higher in youths who began to smoke, or increased their levels of smoking, within the next year. Thus, previous assumptions were partially confirmed. Future research and prevention programming should focus more on regular smoking as the focus of normative smoking distortion effects and correction efforts.  相似文献   
804.
805.
Brian Ellis 《Ratio》2005,18(4):462-472
There are three outstanding issues raised by my critics in this volume. The first concerns the nature and status of universals (John Heil). The second is ‘the essential problem’, which is the issue of how to distinguish the essential properties of natural kinds from their accidental ones, and the related question of whether we really need to believe in the essences of natural kinds (Stephen Mumford). The third is that of strong versus weak dispositional essentialism (Alexander Bird), or equivalently, whether there is any place for categorical properties in an essentialist metaphysic (John Heil). This paper addresses these three issues.  相似文献   
806.
Musically tone-deaf individuals have psychophysical deficits in detecting pitch changes, yet their discrimination of intonation contours in speech appears to be normal. One hypothesis for this dissociation is that intonation contours use coarse pitch contrasts which exceed the pitch-change detection thresholds of tone-deaf individuals (). We test this idea by presenting intonation contours for discrimination, both in the context of the original sentences in which they occur and in a "pure" form dissociated from any phonetic context. The pure form consists of gliding-pitch analogs of the original intonation contours which exactly follow their pattern of pitch and timing. If the spared intonation perception of tone-deaf individuals is due to the coarse pitch contrasts of intonation, then such individuals should discriminate the original sentences and the gliding-pitch analogs equally well. In contrast, we find that discrimination of the gliding-pitch analogs is severely degraded. Thus it appears that the dissociation between spoken and musical pitch perception in tone-deaf individuals is due to a deficit at a higher level than simple pitch-change detection.  相似文献   
807.
Sexual conditioning investigations have primarily used rats and domestic quail as subjects. Although much has been learned from such experiments, the relative simplicity of rat and quail reproductive behavior prohibits investigation of certain experimental questions about sexual conditioning. In contrast, the reproductive behavior of male and female ring doves (Streptopelia risoria) is complex, involving courtship, bonding, and parental care. In the present experiment, male ring doves that were presented with a visual conditioned stimulus paired with access to their pair-bonded mate (the unconditioned stimulus) showed sexual conditioned responding in the presence of the conditioned stimulus. These results represent the first evidence of sexual conditioning in ring doves and illustrate the potential of ring doves as a useful model for future sexual conditioning investigations.  相似文献   
808.
809.
The emergence of competing modules in bilingualism   总被引:5,自引:0,他引:5  
How does the brain manage to store and process multiple languages without encountering massive interference and transfer? Unless we believe that bilinguals live in two totally unconnected cognitive worlds, we would expect far more transfer than actually occurs. However, imaging and lesion studies have not provided consistent evidence for the strict neuronal separation predicted by the theory of modularity. We suggest that emergentist theory offers a promising alternative. It emphasizes the competitive interplay between multiple languages during childhood and by focusing on the dual action of competition and entrenchment, avoids the need to invoke a critical period to account for age of acquisition effects in second-language learning. This view instantiates the motto formulated by Elizabeth Bates that 'modules are made, not born.'  相似文献   
810.
Coherent visual experience of dynamic scenes requires not only that the visual system segment scenes into component objects but that these object representations persist, so that an object can be identified as the same object from an earlier time. Object files (OFs) are visual representations thought to mediate such abilities: OFs lie between lower level sensory processing and higher level recognition, and they track salient objects over time and motion. OFs have traditionally been studied via object-specific preview benefits (OSPBs), in which discriminations of an object's features are speeded when an earlier preview of those features occurred on the same object, as opposed to on a different object, beyond general displaywide priming. Despite its popularity, many fundamental aspects of the OF framework remain unexplored. For example, although OFs are thought to be involved primarily in online visual processing, we do not know how long such representations persist; previous studies found OSPBs for up to 1500 msec but did not test for longer durations. We explored this issue using a modified object reviewing paradigm and found that robust OSPBs persist for more than five times longer than has previously been tested-for at least 8 sec, and possibly for much longer. Object files may be the "glue" that makes visual experience coherent not just in online moment-by-moment processing, but on the scale of seconds that characterizes our everyday perceptual experiences. These findings also bear on research in infant cognition, where OFs are thought to explain infants' abilities to track and enumerate small sets of objects over longer durations.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号