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   24557篇
  免费   900篇
  国内免费   9篇
  25466篇
  2018年   327篇
  2017年   347篇
  2016年   360篇
  2015年   257篇
  2014年   332篇
  2013年   1744篇
  2012年   579篇
  2011年   625篇
  2010年   427篇
  2009年   388篇
  2008年   611篇
  2007年   543篇
  2006年   523篇
  2005年   450篇
  2004年   455篇
  2003年   459篇
  2002年   471篇
  2001年   634篇
  2000年   638篇
  1999年   500篇
  1998年   254篇
  1997年   272篇
  1996年   270篇
  1995年   254篇
  1992年   486篇
  1991年   449篇
  1990年   445篇
  1989年   417篇
  1988年   436篇
  1987年   404篇
  1986年   447篇
  1985年   426篇
  1984年   374篇
  1983年   332篇
  1981年   264篇
  1979年   401篇
  1978年   322篇
  1977年   280篇
  1976年   292篇
  1975年   337篇
  1974年   428篇
  1973年   461篇
  1972年   341篇
  1971年   365篇
  1970年   333篇
  1969年   361篇
  1968年   434篇
  1967年   400篇
  1966年   415篇
  1958年   253篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
941.
Taste and odor have different properties in toxiphobic conditioning. When each is used alone, taste becomes aversive when followed by immediate or delayed poison, while odor becomes aversive only if followed by immediate poison. However, if odor and taste are presented as a compound and followed by delayed poison, then odor does become aversive when tested alone. It is as if taste has potentiated the odor signal. Several experiments assessed the role of the amygdala in this potentiation effect by anesthetizing the amygdala with 10% novocaine. Novocaine applied 30 min before presentation (Pre-CS) of an odor-taste compound disrupted the potentiated odor aversion but not the taste aversion. In contrast, novocaine applied 1 min after the compound odor-taste or 1 min prior to LiCl poison did not dissociate odor and taste aversions; both odor and taste aversions were facilitated. Novocaine applied 30 min before an odor alone also disrupted an odor aversion induced by immediate LiCl. But identical treatment did not disrupt odor avoidance conditioned by immediate foot-shock, suggesting that amygdala anesthesia does not simply produce anosmia. Pre-CS novocaine treatment also disrupted flavor neophobia prior to conditioning. The results suggest that novocaine applied to the amygdala disrupts the integration of odor with taste and illness during toxiphobic conditioning.  相似文献   
942.
Cognitive motivation and drug use: a 9-year longitudinal study.   总被引:2,自引:0,他引:2  
The predictive precedence of expectancy constructs, operationally defined as cognitive motivations, and drug use was investigated over a 9-year period from adolescence to adulthood. Alternative predictions from three different classes of theories of expectancy-behavior relations, including expectancy theory, a Skinnerian approach, and a reciprocal determinism perspective, were evaluated. The results are most consistent with the notion based in expectancy theory that cognitive motivations are nonspurious and possibly functionally autonomous influences on the use and abuse of drugs. More limited support is found for the view that drug use leads to cognitive motivations, as postulated in other theoretical perspectives. Other findings reveal the presence of expectancy generalization processes consistent with Rotter's (1954) expectancy theory, as well as the unique status of cognitive motivations for alcohol as an independent predictor of problem drug use.  相似文献   
943.
We administered scales of Perceptual Aberration (PERAB) and Physical Anhedonia (PHYSAN), traits that may be related to risk for schizophrenia, to 54 schizophrenics, 146 of their first-degree relatives (evaluated for schizophrenia-related disorders), and 178 normal subjects (screened for psychotic disorders in them or their relatives). For both scales, there was a significant effect of group membership. For the PERAB scale, the schizophrenics had higher scores than the normal subjects, who had higher scores than the relatives. For the PHYSAN scale, schizophrenics had higher scores than their relatives, who had higher scores than the normal subjects. Patterns of familial correlations also suggested that physical anhedonia, but not perceptual aberration, may be familial among schizophrenics and their relatives. The PHYSAN scale, but not the PERAB one, may be a useful indicator of liability for schizophrenia among the relatives of affected probands.  相似文献   
944.
945.
The consequences of maternal postpartum depression for mothers and children were investigated in a 4 1/2-year follow-up study, which included 70 of 99 women who had participated in an earlier study of postpartum depression. Information about maternal adjustment and depression during the follow-up period and child adjustment at age 4 1/2 years was obtained. Women who had experienced a postpartum depression were predicted to be at increased risk for subsequent depression and poor adjustment of their child. Postpartum depression was directly related to subsequent depression but not child problems. Later depression was related to child problems at 4 1/2 years. We concluded that postpartum depression may increase risk for later maternal depression and in turn increases risk for child behavior problems. Intervening with women who have experienced a postpartum depression may reduce likelihood of future depressions and child behavior problems.  相似文献   
946.
Emergent themes and roles in short-term loss groups   总被引:1,自引:0,他引:1  
Clinical observations regarding themes and roles that are characteristic of short-term, psychoanalytically oriented therapy groups for loss patients are presented. They reflect aspects of both the therapy and the patients. Themes refer to the content of a recurrent conflict in the group. They include trust, survivor guilt, mortality, and termination. Roles refer to a set of patient behaviors that represent a shared conflict. They include the apparition, monk, professor, professional nurturer, emotional conductor, and cruise director. Challenges that the themes and roles present to the therapist and clinical guidelines for addressing them are offered. Awareness of characteristic themes and roles and possible therapist responses are regarded as important parts of the preparation and training of therapists who plan to conduct short-term loss groups.  相似文献   
947.
W R Burr 《Family process》1991,30(4):435-452
This article is an attempt to improve the way we conceptualize "levels" in family systems. The first section reframes thinking about levels by identifying an array of different ways of thinking about levels. The next section suggests a parsimonious frame-work for thinking about levels of abstraction in systemic processes. The proposed framework integrates several earlier ways of conceptualizing levels, and helps eliminate some of the confusion, inconsistencies, fragmentation, and limitations of some earlier models. The new framework has three categories that are called Levels I, II, and III. The most abstract level (III) includes phenomena such as family paradigms and values. The intermediate level includes processes such as second-order change, regime, and "meta" processes such as metacommunication and meta-rules. The least abstract level refers to specific processes such as transformation processes and rules. The article concludes with an attempt to demonstrate the usefulness of the proposed framework by showing how it can be used to eliminate a number of conceptual problems in earlier models, improve conceptual clarity, help generate new theoretical insights, and help deal with several controversies in the field.  相似文献   
948.
Fibrositis (fibromyalgia) patients were compared with normal controls in terms of electrophysiology (EEG), self-report indicants of awakening, quality of sleep, behaviourally signalled awakenings, and Symptom Check List 90R (SCL-90R) scores. The results differentiated fibrositis patients from normal controls in terms of SCL-90R scores, with fibrositis patients showing significantly more psychopathology. Fibrositis patients had more alpha EEG sleep and less REM and Stage 1 sleep. They were better able to recall their behaviourally signalled awakenings the following morning and reported qualitatively less satisfying sleep than the normal controls. The alpha EEG sleep anomaly may reflect a vigilant arousal state during nocturnal sleep and result in the daytime experience of unrefreshing sleep, psychologic distress, that re-enforces the perpetuation of the sleep-related symptoms.  相似文献   
949.
Social influence processes affecting adolescent substance use   总被引:14,自引:0,他引:14  
Social influence is central to models of adolescent substance use. Nonetheless, researchers fail to delineate the various forms of social influence. A framework that distinguishes between active (explicit drug offers) and passive (social modeling and overestimation of friends' use) social pressure was tested. The effect of these processes on alcohol and cigarette use was examined with 526 seventh graders taking part in an alcohol prevention program. Hierarchical regression analyses demonstrated that pretest measures of alcohol use, offers, modeling, and overestimation each accounted for unique variance in posttest alcohol use. Similar results were obtained for cigarette smoking. The general model was not significantly different for boys and girls, or for prior users and prior nonusers, supporting the generalizability of the framework. Implications for intervention programs are discussed.  相似文献   
950.
Choking under pressure by persons low and high in self-consciousness was examined as a function of two sources of performance pressure: audience and performance feedback. Subjects competed with an alleged opponent on a psychomotor task while alone, before a supportive (same team) audience, or a nonsupportive (opposing team) audience. Before the critical trial, subjects learned that their team was either somewhat ahead of or somewhat behind the opposing team. Self-consciousness, audience, and feedback interacted to affect performance during the critical trial. When disappointing the audience was likely, subjects low in self-consciousness choked. Subjects high in self-consciousness tended to choke when they were told that their team had fallen behind. It is suggested that persons who are low and high in self-consciousness experience different types of performance pressure due to disparate self-presentational motives.  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