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   82216篇
  免费   3386篇
  国内免费   37篇
  85639篇
  2020年   929篇
  2019年   1126篇
  2018年   1602篇
  2017年   1675篇
  2016年   1699篇
  2015年   1233篇
  2014年   1441篇
  2013年   6986篇
  2012年   2662篇
  2011年   2754篇
  2010年   1704篇
  2009年   1715篇
  2008年   2427篇
  2007年   2336篇
  2006年   2164篇
  2005年   1825篇
  2004年   1795篇
  2003年   1779篇
  2002年   1667篇
  2001年   2763篇
  2000年   2651篇
  1999年   1955篇
  1998年   954篇
  1997年   793篇
  1996年   863篇
  1995年   775篇
  1994年   778篇
  1993年   762篇
  1992年   1640篇
  1991年   1533篇
  1990年   1498篇
  1989年   1421篇
  1988年   1387篇
  1987年   1317篇
  1986年   1271篇
  1985年   1384篇
  1984年   1105篇
  1983年   929篇
  1979年   1135篇
  1978年   858篇
  1977年   742篇
  1975年   961篇
  1974年   1052篇
  1973年   1116篇
  1972年   927篇
  1971年   828篇
  1969年   752篇
  1968年   942篇
  1967年   811篇
  1966年   840篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
111.
112.
113.
A square-wave grating from which the fundamental harmonic has been subtracted (missing fundamental grating) when viewed from a suitable distance appears similar to another grating of periodicity three times higher. The neurons of the visual cortex of the cat, in a given range of spatial frequencies characteristic of each cell, give similar responses to the two gratings.  相似文献   
114.
115.
116.
A Black feminist model was used to investigate rape myth acceptance between African American antirape activists and a comparison group of nonactivists using Cross's (1991) racial identity model and Downing and Roush's (1985) feminist identity model. As predicted, activists rejected rape myths more than nonactivists; the earlier stages of both models were associated with rape myth acceptance; the later stages were associated with rape myth rejection; and activists evidenced more sociopolitical maturity (race and gender consciousness) than nonactivists. The findings suggest that researchers may need to investigate to what degree rape myth acceptance serves an overarching system of social domination where racism and sexism overlap.  相似文献   
117.
Native Hawaiian high school students, N = 1779, were surveyed for symptoms of psycho-pathology and suicide attempts in the previous 6 months. Seventy-seven (4.3%) of the students reported making a suicide attempt. There were no significant differences in prevalence rates for males and females. Depression, anxiety, aggression, substance abuse symptoms, and low family support, but not peer support, were significantly correlated with suicide attempts. On logistic regression, depression, substance abuse, and family support independently predicted attempts. The lack of gender difference may indicate a cultural characteristic of the Hawaiian population that differentiates it from mainstream American populations but likens it to the Native American population.  相似文献   
118.
Previous research has revealed that individuals have expectations for the development of romance based on personal experience and cultural images. A series of research questions and hypotheses was generated and a sequence of hierarchical log-linear analysis models axis developed to test (a) the effect of gender and knowledge of relational stage and relationship type on prediction of next-occurring actions in the development of a romance, (b) the use of compliance-gaining strategies intended to advance a relationship to the next stage, and (c) justification of secondary goals in which participants reported why they chose the strategies they did as opposed to other alternatives. The data revealed effects for relational stage progression on prediction of ensuing actions. Ingratiation, explanation, and direct requests were popular strategies for developing intimacy. Gender differences in terms of secondary goals were reported. Results are discussed in terms of relational memory structures for the development of intimacy.  相似文献   
119.
The purpose of this meta-analysis of randomized controlled trials was to evaluate the efficacy of psychological interventions for adults with noncancerous chronic low back pain (CLBP). The authors updated and expanded upon prior meta-analyses by using broad definitions of CLBP and psychological intervention, a broad data search strategy, and state-of-the-art data analysis techniques. All relevant controlled clinical trials meeting the inclusion criteria were identified primarily through a computer-aided literature search. Two independent reviewers screened abstracts and articles for inclusion criteria and extracted relevant data. Cohen's d effect sizes were calculated by using a random effects model. Outcomes included pain intensity, emotional functioning, physical functioning (pain interference or pain-specific disability, health-related quality of life), participant ratings of global improvement, health care utilization, health care provider visits, pain medications, and employment/disability compensation status. A total of 205 effect sizes from 22 studies were pooled in 34 analyses. Positive effects of psychological interventions, contrasted with various control groups, were noted for pain intensity, pain-related interference, health-related quality of life, and depression. Cognitive-behavioral and self-regulatory treatments were specifically found to be efficacious. Multidisciplinary approaches that included a psychological component, when compared with active control conditions, were also noted to have positive short-term effects on pain interference and positive long-term effects on return to work. The results demonstrated positive effects of psychological interventions for CLBP. The rigor of the methods used, as well as the results that reflect mild to moderate heterogeneity and minimal publication bias, suggest confidence in the conclusions of this review.  相似文献   
120.
A theoretical structure for multiattribute decision making is presented, based on a dynamical system for interactions in a neural network incorporating affective and rational variables. This enables modeling of problems that elude two prevailing economic decision theories: subjective expected utility theory and prospect theory. The network is unlike some that fit economic data by choosing optimal weights or coefficients within a predetermined mathematical framework. Rather, the framework itself is based on principles used elsewhere to model many other cognitive and behavioral data, in a manner approximating how humans perform behavioral functions. Different, interconnected modules within the network encode (a) attributes of objects among which choices are made, (b) object categories, (c) and goals of the decision maker. An example is utilized to simulate the actual consumer choice between old and new versions of Coca-Cola. Potential applications are also discussed to market decisions involving negotiations between participants, such as international petroleum traders.  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