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   50555篇
  免费   2080篇
  国内免费   34篇
  2020年   524篇
  2019年   665篇
  2018年   928篇
  2017年   932篇
  2016年   1038篇
  2015年   724篇
  2014年   856篇
  2013年   4004篇
  2012年   1554篇
  2011年   1578篇
  2010年   932篇
  2009年   984篇
  2008年   1287篇
  2007年   1374篇
  2006年   1185篇
  2005年   1061篇
  2004年   1029篇
  2003年   957篇
  2002年   998篇
  2001年   1677篇
  2000年   1634篇
  1999年   1227篇
  1998年   517篇
  1996年   494篇
  1995年   484篇
  1992年   1007篇
  1991年   952篇
  1990年   944篇
  1989年   884篇
  1988年   887篇
  1987年   812篇
  1986年   823篇
  1985年   863篇
  1984年   700篇
  1983年   628篇
  1982年   495篇
  1979年   787篇
  1978年   558篇
  1977年   494篇
  1976年   492篇
  1975年   612篇
  1974年   751篇
  1973年   787篇
  1972年   655篇
  1971年   598篇
  1970年   577篇
  1969年   562篇
  1968年   716篇
  1967年   628篇
  1966年   596篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
We evaluated the effects of adding a social support component to a worksite controlled smoking treatment program. Twenty-four participants were randomly assigned to either a controlled smoking or a controlled smoking plus partner support condition. Within a multiple baseline across behaviors design, smokers in both conditions made efforts to achieve sequential 50% reductions in: (a) nicotine content of brand smoked, (b) number of cigarettes smoked per day, and (c) percentage of each cigarette smoked. Self-monitoring records, laboratory analyses of spent cigarette butts, and carbon monoxide determinations indicated that both conditions were effective in producing significant reductions in each of the three target behaviors and in carbon monoxide levels. All participants who quit smoking during the program maintained their abstinence at a 6-month follow-up, and those who did not quit were smoking less at follow-up than they had at pretest on all dependent variables. However, few differences were observed between controlled smoking and controlled smoking plus partner support conditions either during treatment or at the 6-month follow-up. Results are discussed with regard to previous worksite studies, future directions for research on social support, and variables that may have mediated treatment outcome.  相似文献   
993.
994.
Five-year-old children were tested for perceptual trading relations between a temporal cue (silence duration) and a spectral cue (F1 onset frequency) for the “say-stay” distinction. Identification functions were obtained for two synthetic “say-stay” continua, each containing systematic variations in the amount of silence following the /s/ noise. In one continuum, the vocalic portion had a lower F1 onset than in the other continuum. Children showed a smaller trading relation than has been found with adults. They did not differ from adults, however, in their perception of an “ay-day” continuum formed by varying F1 onset frequency only. The results of a discrimination task in which the two acoustic cues were made to “cooperate” or “conflict” phonetically supported the notion of perceptual equivalence of the temporal and spectral cues along a single phonetic dimension. The results indicate that young children, like adults, perceptually integrate multiple cues to a speech contrast in a phonetically relevant manner, but that they may not give the same perceptual weights to the various cues as do adults.  相似文献   
995.
Five experiments are reported on the symbolic distance effect (SDE) and related phenomena with 6- and 9-year-old children. In the first of these, children were asked to judge the relative sizes of animals in verbal and pictorial tests featuring the comparatives "bigger" and "smaller." A perceptual condition with actual objects was included by way of comparison. A Symbolic Distance Effect was obtained for both lexical and pictorial input. Mode differences were also observed. Pictures produced faster responses than words, and congruity effects occurred only in the pictorial condition. Although performance was similar in tests with either comparative, our subsequent experiments on both 6- and 9-year-olds reveal a significant asymmetry in the child's capacity to verify statements of relation as a function of the direction along the (size) continuum implied by the question. However, important differences between age groups also apparent in the data lead us to conclude that the older subjects develop strategies to overcome this asymmetry by translating certain statements of relation into a form more congruent with their natural modes of encoding.  相似文献   
996.
In three experiments, the effect of additional "contextual" elements on the discrimination of the orientation of linear and curvilinear segments was investigated with 4-month-old infants. In Experiment 1, paired visual matrices (one which contained some irregularity in orientation of internal elements, vs one which contained no irregularities) were presented. Infants detected irregular matrices significantly better than chance, but such detection was not aided by contextual elements. Discrimination of orientation in Experiment 2 was assessed with a paired-comparison familiarization-novelty paradigm. It was found that the addition of elements here significantly aided discrimination of linear segment orientation, but not curvilinear segment orientation. Experiment 3 investigated why this effect was not found for curvilinear segments; after equating the curvilinear stimuli to linear ones used in Experiment 2 with respect to the closedness of figure, discrimination of curvilinear orientation was observed.  相似文献   
997.
This study investigated the effect of television-mediated aggression and real-life aggression on the behavior of Lebanese children. The sample consisted of 48 boys and 48 girls of Lebanese origin who were students in an elementary school in Beirut, Lebanon. After controlling for pre-experimental aggression, the subjects were randomly assigned to one of the following treatment conditions: human-film aggression, cartoon-film aggression, neutral film, or real-life (act of war) aggression. The results indicated that boys as a group were more aggressive than girls and exhibited more imitative aggression after viewing both violent film and real-life violence. Girls were not more violent after viewing filmed aggression but were affected by the real-life violence. Comparisons of Bandura's work within the Lebanese culture are made.  相似文献   
998.
Figure drawings obtained from 758 white male medical students were scored using three different methods. Method I involved 16 different physical size measurements; Method II involved six separate sophistication of body concept ratings; and Method III involved 42 separate aspects of the drawings weighted in direct proportion to their relative frequency of occurrence in the sample studied (conventionality scoring). Separate factor analyses of the scores derived from each method revealed that Methods I and II each reflect only a single underlying factor, and that these factors are uncorrelated in the population studied. Method III yielded eight meaningful factors, each of which may be construed as an independent area of conventionality/deviancy. An overall conventionality/deviancy score was also derived. It is believed that these three methods of scoring capture most of the variance inherent in existing figure drawing scoring systems, but that use of all three is necessary for a comprehensive analysis.  相似文献   
999.
The purpose of the present study was to investigate the influence of race (black, white) on the MMPI performance of alcoholic and nonalcoholic inpatients. Subjects were 73 (27 black, 46 white) male alcoholic inpatients and 73 (27 black, 46 white) male nonalcoholic psychiatric inpatients. While black and white alcoholics failed to differ on the MMPI, white alcoholics presented as less disturbed and black alcoholics as less defensive and distressed, compared to their respective nonalcoholic counterparts. Furthermore, only white alcoholics were accurately identified by the MMPI 2-4/4-2 high-point pair combination and only white alcoholics achieved more high-point pairs containing Scale 4 relative to nonalcoholic controls.  相似文献   
1000.
Research on the color-shading response on the Rorschach has been limited previously to its use as a predictor of suicide. The theoretical understanding of this response was addressed by some of the major Rorschach authors. Adult cystic fibrosis patients were administered a battery of psychological tests, including the Rorschach. While these patients face a premature death, none of these patients were suicidal. A higher than usual incidence of color-shading responses occurred. Rapaport's hypothesis that the color-shading response is an expression of a simultaneously conflicting emotion, or similar to "sweet sorrow," was suggested as a possible hypothesis.  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