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   8843篇
  免费   334篇
  国内免费   1篇
  2020年   108篇
  2019年   142篇
  2018年   166篇
  2017年   196篇
  2016年   225篇
  2015年   167篇
  2014年   212篇
  2013年   975篇
  2012年   337篇
  2011年   333篇
  2010年   243篇
  2009年   222篇
  2008年   320篇
  2007年   301篇
  2006年   293篇
  2005年   269篇
  2004年   279篇
  2003年   260篇
  2002年   301篇
  2001年   122篇
  2000年   115篇
  1999年   137篇
  1998年   142篇
  1997年   131篇
  1996年   114篇
  1995年   137篇
  1994年   115篇
  1993年   106篇
  1992年   111篇
  1991年   106篇
  1990年   94篇
  1989年   89篇
  1988年   72篇
  1987年   72篇
  1986年   73篇
  1985年   90篇
  1984年   111篇
  1983年   124篇
  1982年   119篇
  1981年   151篇
  1980年   107篇
  1979年   128篇
  1978年   131篇
  1977年   117篇
  1976年   103篇
  1975年   109篇
  1974年   111篇
  1973年   71篇
  1972年   67篇
  1969年   61篇
排序方式: 共有9178条查询结果,搜索用时 15 毫秒
271.
Premise acceptability is conceptually connected to presumption. To say that a premise is acceptable just when there is a presumption in its favor is to give a first approximation to this connection. A number of popular principles of presumption suggest that whether there is a presumption for a premise, belief, or claim depends on the sources which vouch for it. Sources consist of internal belief-generating mechanisms and external testimony. Alvin Plantinga's notion of warrant lays down four conditions upon a source for the belief which it generates to be warranted. We argue that there is a presumption for a premise, belief, or claim if and only if there is a presumption of warrant for that premise,belief or claim. This amounts to the thesis that there is a presumption for a belief from a challenger's point of view if and only if there is a presumption from that person's point of view that her cognitive faculties which have generated the belief have been functioning properly, in an appropriate cognitive environment, in accord with a segment of her design plan aimed at the truth, and that these faculties are reliable. In light of our argument for this thesis, we may legitimately claim that one way to determine that there is a presumption for a belief is to determine that there is a presumption of warrant for that belief, and thus that in determining whether there is a presumption for a belief or premise, we may consider the source.  相似文献   
272.
Fourier analysis describes the amount of variation in a time series by partitioning it into sinusoids of different amplitudes and wavelengths and quantifying the extent to which these waves are synchronized. The importance of a given wave is represented by its contribution to the explained variance of the time series. To illustrate its potential application to the study of movement, Fourier analysis was used to quantify the movement patterns of 2 pigeons on a variable-interval (VI) and a variable-time (VT) schedule of reinforcement. For comparison, the movements of 2 pigeons that did not receive reinforcement were similarly analyzed. Characteristic frequencies were higher during VI than during VT, and relatively low during nonreinforcement. We concluded that Fourier analysis can be used to represent movement patterns compactly, study their periodicity, stereotypy, and resonance, and assist in computer simulations and models of movement.  相似文献   
273.
It is now relatively easy to implement pupillometry in social psychological research. We describe a system in which a Macintosh computer presents visual and auditory stimuli to subjects while monitoring an infrared pupillometer. The computer records information on subject, task, and pupil diameter into a data file for input into standard statistical analysis programs. Pupil diameter is measured continuously while subjects respond to stimuli that last for several seconds or minutes. A demonstration experiment verifies the usefulness of the system. The ability of the Macintosh computer to easily handle visual and auditory stimuli and to record responses lasting a considerable length of time makes the system well suited for studying pupil responses to complex social stimuli. This system is also well suited for the researcher initiating a research program using pupillometry. Ease of operation makes using a large number of subjects feasible.  相似文献   
274.
In this article a brief overview of the treatment of chronic psychosis for the last two centuries is covered, with particular emphasis on many scientifically demonstrated causes of chronic organic psychosis and their medically successful treatment, including recent neurotransmitter manipulations. With respect for the important contributions of Bleuler, the term “schizophrenic” is considered as an unscientific and unprovable nosological construct, which has hampered the successful resolution of chronic psychosis and has outlived its usefulness in the lexicon of modern psychiatry.  相似文献   
275.
The aim of these experiments was to determine whether impaired retention performance in aversively motivated tasks, induced by blockade of amygdala AMPA receptors, is due to influences on mechanisms underlying memory retrieval or to other influences on performance. Rats received either footshock escape training (1 or 10 trials), or no foot shock, in a two-compartment straight alley and bilateral intra-amygdala infusions of the AMPA receptor antagonist CNQX (0.5 μg) were subsequently administered prior to inhibitory avoidance retention testing 8 days later. The CNQX impaired, but did not block, inhibitory avoidance retention performance as indicated by the initial latencies to enter the shock compartment. The animals were then retained in the alley until they remained in the starting compartment for 100 consecutive s and entries into the shock compartment were recorded as errors. In both the controls and CNQX-treated groups, increases in amount of original training resulted in fewer errors, indicating memory for the escape training. Furthermore, regardless of the amount of original training (i.e., 0, 1, or 10 trials), CNQX-treated groups made more errors. Other experiments examined intra-amygdala CNQX effects on reactivity to footshock, locomotor activity, and anxiety. CNQX decreased reactivity to footshock, blocked shock-induced decreases in locomotor activity, and had an anxiolytic effect in an elevated plus maze comparable to that induced by midazolam (0.5 μg). These findings suggest that intra-amygdala infusions of CNQX prior to retention testing affect inhibitory avoidance retention performance following aversive training by altering locomotor activity, reducing sensitivity to footshock, and reducing anxiety. The implications of these findings for hypotheses concerning amygdala function in aversively motivated learning and memory is discussed.  相似文献   
276.
Some aspect of psychosocial criteria is commonly utilized by most transplant programs in assessing candidates' acceptability for transplantation. However, regardless of the assessment methodology, information obtained in pretransplant assessments may be limited given the evaluative nature of the assessment as well as the sensitive nature of the contents. Indeed, transplant candidates may present themselves in a favorable fashion, minimizing any negative traits or psychological dysfunction which they perceive might prevent transplantation. Unfortunately, there are limited data addressing the extent to which transplant candidates may present themselves in an overly positive light. This investigation surveys the prevalence of social desirability in lung transplant candidates as well as its association with self-reports of perceived stress. Further, the relationship between social desirability and interviewer ratings of transplant candidacy is examined. Subjects included 24 patients in end-stage organ failure being evaluated for lung transplant candidacy. Subjects completed the Perceived Stress Scale and a brief version of the Marlowe-Crowne Social Desirability Scale. Additionally, subjects were interviewer-rated on the Psychosocial Assessment of Candidates for Transplantation. Results indicate social desirability is a prevalent phenomenon in lung transplant candidates, with more than half of the sample scoring at or above the 84th percentile on the social desirability measure. Further, self-reports of perceived stress are moderately and inversely associated with social desirability (r=–.55,p .01). Social desirability was unrelated to interviewer-ratings of transplant candidates acceptability (r=.13,p .56). Future research might include larger samples of subjects, other organ transplant candidates, and more detailed assessments of symptom distress.  相似文献   
277.
Four experiments investigated observers’ judgments of rigidity for different types of optical motion. The depicted structural deformations were of two types: (1) those with nonparallel image trajectories that are detectable from the first-order spatiotemporal relations between pairs of views; and (2) those with parallel image trajectories that can only be detected from higher order relations among three or more views. Patterns were composed of smooth flow fields in Experiments 1 and 3, and of wire frame figures in Experiments 2 and 4. For both types of display, the nonrigidity detectable from the first-order spatiotemporal structure of the motion sequence was much more salient than the deformation detectable only from the higher order spatiotemporal structure. These results indicate that observers’ judgments of rigidity are based primarily on a two-view analysis, but that some useful information can be obtained under appropriate circumstances from higher order spatiotemporal relations among three or more views.  相似文献   
278.
279.
The concept of a curative fantasy includes patient's conscious and unconscious hopes and expectations of what is necessary for their relief of suffering. On entering group psychotherapy these elements emerge in the treatment matrix. This paper describes how patients with significant deficits in their intrapsychic organization express their curative fantasies through the development of selfobject transferences. The concept illuminates aspects of patients entering and forming a group as well as some elements in unanticipated terminations.  相似文献   
280.
Situational performance constraints, task interest, and pay contingencies were manipulated in a laboratory study in order to investigate the cognitive mechanisms associated with the previously observed detrimental effects of constraints on affective task reactions. It was hypothesized that feelings of task competence and self-determination would account for both the direct and the interactive effects of constraints on motivation and satisfaction. The results of the study indicated that despite the fact that participants' performance was being constrained and they were aware of these constraints, the mere presence of the constraints alone failed to result in lower levels of satisfaction or motivation on a proofreading task. Post hoc analyses suggested that the constraints, in fact, led to negative affective task reactions when they also reduced participants' feelings of competence and self-determination. Interestingly, participants' generalized locus of control was associated with such effects. Internals tended to maintain stronger feelings of competence and self-determination than externals in the presence of constraints, thereby also maintaining greater motivation and satisfaction.  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