全文获取类型
收费全文 | 59029篇 |
免费 | 2382篇 |
国内免费 | 18篇 |
专业分类
61429篇 |
出版年
2020年 | 547篇 |
2019年 | 734篇 |
2018年 | 978篇 |
2017年 | 1006篇 |
2016年 | 1070篇 |
2015年 | 781篇 |
2014年 | 919篇 |
2013年 | 4300篇 |
2012年 | 1724篇 |
2011年 | 1886篇 |
2010年 | 1165篇 |
2009年 | 1155篇 |
2008年 | 1671篇 |
2007年 | 1687篇 |
2006年 | 1541篇 |
2005年 | 1358篇 |
2004年 | 1254篇 |
2003年 | 1178篇 |
2002年 | 1290篇 |
2001年 | 1959篇 |
2000年 | 1936篇 |
1999年 | 1463篇 |
1998年 | 681篇 |
1997年 | 605篇 |
1996年 | 605篇 |
1993年 | 546篇 |
1992年 | 1236篇 |
1991年 | 1136篇 |
1990年 | 1123篇 |
1989年 | 1024篇 |
1988年 | 1008篇 |
1987年 | 963篇 |
1986年 | 1039篇 |
1985年 | 1046篇 |
1984年 | 875篇 |
1983年 | 797篇 |
1982年 | 559篇 |
1981年 | 557篇 |
1979年 | 933篇 |
1978年 | 665篇 |
1975年 | 760篇 |
1974年 | 814篇 |
1973年 | 907篇 |
1972年 | 766篇 |
1971年 | 722篇 |
1970年 | 642篇 |
1969年 | 668篇 |
1968年 | 855篇 |
1967年 | 775篇 |
1966年 | 651篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
241.
Dinsmoor JA Dougan JD Pfister J Thiels E 《Journal of the experimental analysis of behavior》1992,58(2):265-276
In the first experiment, 4 pigeons were each presented with a recurring sequence of four key colors followed by the delivery of grain (block clock). Once the rate of pecking had stabilized, three of the colors were replaced, during different series of sessions, by a darkening of the key. The rate of pecking was reduced within those segments of the interval between deliveries of food during which the key was dark; when the key was dark during the final portion of the interval, rates were reduced throughout the entire interval. In the second experiment, 3 new pigeons were exposed to a different sequence of colors, and the final stimulus was replaced in successive conditions by a novel color, a darkened key, and a restoration of the original color. The data indicated that darkening the key had a more severe, more extensive, and more persistent effect than did a mere change in color. These results suggest that it may be fruitful to conceptualize the autoshaping procedure as a special version of the block clock in which pecking is suppressed throughout the greater part of the interval by darkening the key. In the final condition, the same stimulus appeared in each of the last three portions of the interval. The rate of pecking was lower during the last two portions than when distinctive colors were presented, with the peak rate now appearing in the fifth of seven equal temporal components. 相似文献
242.
J Panksepp 《Psychological review》1992,99(3):554-560
Ortony and Turner (1990) asked "What's Basic About Basic Emotions," and they concluded "very little." They proceeded to advocate a "componential" or "mosaic" view of how emotional systems should be analyzed. Their thesis was flawed by their failure to consider the available neurobehavioral data. Genetically dictated brain systems that mediate affective-emotional processes do exist, even though there are bound to be semantic ambiguities in how we speak about these systems. This commentary summarizes key lines of evidence for coherently operating emotional systems in the brain and advocates the position that the issue of basic emotions can no longer be credibly discussed without adequate consideration of the relevant brain research in the area. The type of conceptual, logical analysis pursued by Ortony and Turner, in the absence of a thorough analysis of the available neurological data, is not an adequate basis for resolving what is basic about basic emotions. 相似文献
243.
ALCOVE: an exemplar-based connectionist model of category learning. 总被引:16,自引:0,他引:16
J K Kruschke 《Psychological review》1992,99(1):22-44
ALCOVE (attention learning covering map) is a connectionist model of category learning that incorporates an exemplar-based representation (Medin & Schaffer, 1978; Nosofsky, 1986) with error-driven learning (Gluck & Bower, 1988; Rumelhart, Hinton, & Williams, 1986). Alcove selectively attends to relevant stimulus dimensions, is sensitive to correlated dimensions, can account for a form of base-rate neglect, does not suffer catastrophic forgetting, and can exhibit 3-stage (U-shaped) learning of high-frequency exceptions to rules, whereas such effects are not easily accounted for by models using other combinations of representation and learning method. 相似文献
244.
Disorder as harmful dysfunction: a conceptual critique of DSM-III-R's definition of mental disorder.
J C Wakefield 《Psychological review》1992,99(2):232-247
The Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; DSM-III-R) operationally defines disorder essentially as "statistically unexpectable distress or disability." This definition is an attempt to operationalize 2 basic principles: that a disorder is harmful and that a disorder is a dysfunction (i.e., an inability of some internal mechanism to perform its natural function). However, the definition fails to capture the idea of "dysfunction" and so fails to validly distinguish disorders from nondisorders, leading to invalidities in many of DSM-III-R's specific diagnostic criteria. These problems with validity are traced to DSM-III-R's strategies for increasing reliability. 相似文献
245.
246.
104 women, between the ages of 18 and 45 years, were surveyed to investigate the relationship between premenstrual symptomatology, as measured by the Modified Menstrual Distress Questionnaire, and irrational thinking, as measured by the General Attitude and Belief Scale. The women who reported greater premenstrual symptomatology also reported significantly higher scores in the "need for comfort" irrationality subscale. This indicated that these women had particular difficulty dealing with hassles and the resulting feelings of tension and irritability in the premenstruum. It was suggested that the absence of significant effects for other rationality-irrationality subscales could be associated with testing at different times during the menstrual cycle. Irrationality, like other conditions (such as anxiety and depression) prevalent in the premenstruum, could change in intensity across phases of the menstrual cycle. 相似文献
247.
106 high school students from a small rural high school completed the Children of Alcoholics Scale, Zaks and Walters' Aggression Scale, Beck Depression Scale, and a modified version of the Beck Scale of Suicide Ideation. Analyses of variance showed boys were not experiencing suicide ideation any more than girls; suicide ideation was similar across the four grades, but on aggression alcohol-dependent boys scored significantly higher than girls, and in Grade 9 boys' scores were significantly higher than those in Grade 10. The sophomores' scores on alcohol dependency were significantly lower than the freshmen's scores. Boys and children from divorced homes had higher scores on aggression than girls and children from nondivorced homes. Children from homes in which alcohol was used had higher depression scores than children from nonalcoholic homes. Freshman girls and sophomore boys had higher depression scores than senior boys and girls. A Pearson r of 0.28 between scores on alcohol dependency and suicide ideation was significant, but research is needed to understand better the associations of thoughts of suicide and drug-alcohol dependency among these high school students so strategies for prevention and intervention can be focused. 相似文献
248.
The scores of 15 adolescents who had a primary diagnosis of Posttraumatic Stress Disorder, 21 of Conduct Disorder, and 23 control subjects on the Beck and Reynolds depression scales were correlated .58 over-all, .73 for the Posttraumatic group, .48 for the Conduct Disordered group, but .37 for controls. The Reynolds scale did not identify depression in these adolescents as effectively as did the Beck scale. 相似文献
249.
250.
Analyses of responses from a clinical sample of 120 patients (primarily schizophrenics) and from 158 college students to the Cognitive Slippage Scale, a scale designed by Miers and Raulin to identify speech deficits and confused thinking in schizophrenic and schizotypal personality disorders showed high internal reliability; Cronbach's coefficients alpha were .89 and .86 in the clinical and college student samples, respectively. The mean scale scores significantly differentiated the two samples. Also, change scores over 4 wk. showed adequate stability for both samples. Item analysis indicated Items 11, 20, 21, and 28 may not reliably discriminate between schizophrenic and college student samples. Over-all, these preliminary results are consistent with the reliability and validity of the scale. 相似文献