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   9381篇
  免费   532篇
  国内免费   3篇
  2023年   67篇
  2022年   51篇
  2021年   110篇
  2020年   177篇
  2019年   236篇
  2018年   288篇
  2017年   342篇
  2016年   356篇
  2015年   264篇
  2014年   282篇
  2013年   1078篇
  2012年   487篇
  2011年   499篇
  2010年   299篇
  2009年   296篇
  2008年   392篇
  2007年   401篇
  2006年   324篇
  2005年   357篇
  2004年   339篇
  2003年   305篇
  2002年   288篇
  2001年   154篇
  2000年   167篇
  1999年   145篇
  1998年   119篇
  1997年   104篇
  1996年   116篇
  1995年   105篇
  1994年   84篇
  1993年   80篇
  1992年   102篇
  1991年   87篇
  1990年   84篇
  1989年   68篇
  1988年   72篇
  1987年   62篇
  1986年   71篇
  1985年   81篇
  1984年   82篇
  1983年   69篇
  1982年   82篇
  1981年   75篇
  1980年   58篇
  1979年   64篇
  1978年   55篇
  1977年   79篇
  1976年   47篇
  1975年   50篇
  1973年   50篇
排序方式: 共有9916条查询结果,搜索用时 15 毫秒
131.
In November 1990 the National Institute of Mental Health (NIMH) convened a special conference of over 100 scientists and leaders to outline specific strategies and research initiatives that should be developed to implement the recently released National Plan for Research on Child and Adolescent Mental Disorders.Participants included journal editors, educators from psychology and psychiatry, representatives from private foundations, and leaders of research program areas in public funding agencies. Critical knowledge gaps were identified in five areas of child and adolescent psychopathology, including depression, attention deficit hyperactivity disorder, conduct disorder, the anxiety disorders, and the developmental disorders. For each of these areas, special emphasis was placed on developing new ideas and obtaining critical input from other areas of investigation. This report summarizes the identified research gaps and recommends research initiatives to implement the National Plan, as outlined by the conference participants.  相似文献   
132.
Job Satisfaction Among Ethnic Minorities in The Netherlands   总被引:1,自引:0,他引:1  
  相似文献   
133.
Three cases from a larger review of child abuse inquiry reports are discussed. The abuse the children suffered is termed 'not-existing' because they had been shut away until they perished. Interaction between the children's caretakers and the child protection professionals is examined within a revised framework of the double-bind.  相似文献   
134.
Escape and avoidance that are disproportional to the danger of the pertinent stimulus are important clinical problems that are often related to inaccurate (catastrophic) expectations. One possible source of such expectations is a prior, underestimated aversive experience. In the present experiment the hypotheses that underestimated pain leads to escape and that it leads to avoidance were tested. In order to control for the effect of the intensity of the pain stimulus, a control group that received 20 pain stimuli of high intensity was formed. Subjects in the experimental condition received 17 pain stimuli of low intensity and 3 of (unexpectedly) high intensity (experimentally induced underprediction). Underprediction of the high intensity stimulus was significantly related to escape, but not to avoidance. The results suggest that the way in which avoidance was operationalized accounts for this. The strong support of the hypothesized relationship between underpredicted pain and escape is an important finding, however.  相似文献   
135.
Conceptual complexity is a personality characteristic that involves the individual's ability to differentiate and integrate aspects of information. It is usu ally measured with the Paragraph Completion Test (PCT), which requires the completion of six paragraphs, in response to standard stems, often with a time limit of 100-120 sec each. In order to eliminate time pressure, which may reduce complexity, the current study evaluated a revised format that used only two stems but allowed 8 minutes per response. As expected, this procedure resulted in higher scores and produced enough written output to allow analysis of particular test components. Complexity scores from 277 university students were related to total number of words written, sentence length, and number of words with more than three syllables, but not to standard formulae designed to measure readability, such as the Flesch, SMOG and FOG indices. The modest size of the obtained correlations suggests that the scoring of conceptual complexity on the basis of semantic content cannot be replaced by indices based on linguistic and textual components.  相似文献   
136.
Recently several philosophers of science have proposed what has come to be known as the semantic account of scientific theories. It is presented as an improvement on the positivist account, which is now called the syntactic account of scientific theories. Bas van Fraassen claims that the syntactic account does not give a satisfactory definition of empirical adequacy and empirical equivalence. He contends that his own semantic account does define these notations acceptably, through the concept of embeddability, a concept which he claims cannot be defined syntactically. Here, I define a syntactic relation which corresponds to the semantic relation of embeddability. I suggest that the critical differences between the positivist account and van Fraassen's account have nothing to do with the distinction between semantics and syntax.  相似文献   
137.
138.
This case study concerns an 18-year-old bilingual girl who suffered a radiation lesion in the left (dominant) thalamic and temporal region when she was 4 years old. Language and memory assessment revealed deficits in auditory short-term memory, auditory word comprehension, nonword repetition, syntactic processing, word fluency, and confrontation naming tasks. Both languages (English and Dutch) were found to be affected in a similar manner, despite the fact that one language (English) was acquired before and the other (Dutch) after the period of lesion onset. Most of the deficits appear to be related to verbal (short-term) memory dysfunction. Several hypotheses of subcortical involvement in memory processes are discussed with reference to existing theories in this area.  相似文献   
139.
Rate variables and automatized naming in developmental dyslexia   总被引:2,自引:0,他引:2  
The rate variable in rapid automatized naming (RAN) was investigated in 50 adolescent and 40 adult students with developmental dyslexia, in matched normal controls, and in learning-disabled students without reading difficulties. Visual stimuli depicting familiar colors and common objects were presented in isolation at three film speeds and three exposure times. Film speed and exposure time contributed as independent variables to error rate; and dyslexic subjects of both age groups made significantly more naming errors than controls. Dyslexic subjects also responded with longer naming latencies than controls when the same RAN stimuli were presented in a continuous sequential mode as a matrix of rows and columns. Naming latencies in the sequential presentation were highly correlated with naming errors in the film version. The implications of reduced naming rates for nongraphological stimuli in developmental dyslexia are discussed.  相似文献   
140.
Transparent layer constancy   总被引:1,自引:0,他引:1  
Perceived transparency was studied as a constancy problem. In the episcotister (E-) model of scission, luminances are partitioned into layer and background components; four luminances determine values of two layer parameters that specify constancy of a transparent layer on different backgrounds. The E-model was tested in an experiment in which 12 Ss matched 24 pairs of four-luminance patterns by adjusting two luminances of the comparison pattern. Both the standard and the comparison were perceived as a transparent layer on a checkerboard. The E-model predicts matches when layer values are identical in the two patterns. One parameter was constant, constraining the adjustment along the second dimension. Obtained values corresponded well with E-predictions. Alternative models based on local luminance or average contrast ratios accounted for less variability. Results indicate that transparency models should utilize luminance, not reflectance, as the independent variable.  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