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   66989篇
  免费   2710篇
  国内免费   36篇
  69735篇
  2020年   748篇
  2019年   928篇
  2018年   1357篇
  2017年   1348篇
  2016年   1433篇
  2015年   988篇
  2014年   1162篇
  2013年   5792篇
  2012年   2126篇
  2011年   2306篇
  2010年   1370篇
  2009年   1380篇
  2008年   2085篇
  2007年   2074篇
  2006年   1847篇
  2005年   1659篇
  2004年   1601篇
  2003年   1530篇
  2002年   1543篇
  2001年   2143篇
  2000年   2026篇
  1999年   1579篇
  1998年   824篇
  1997年   728篇
  1996年   680篇
  1995年   681篇
  1994年   627篇
  1993年   669篇
  1992年   1243篇
  1991年   1185篇
  1990年   1175篇
  1989年   1059篇
  1988年   1043篇
  1987年   1025篇
  1986年   1006篇
  1985年   1062篇
  1984年   888篇
  1983年   768篇
  1982年   637篇
  1979年   869篇
  1978年   663篇
  1976年   624篇
  1975年   776篇
  1974年   832篇
  1973年   834篇
  1972年   719篇
  1971年   630篇
  1968年   728篇
  1967年   677篇
  1966年   609篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
Prior surgical implantation of a venous catheter sensitized rats to coldimmobilization stress. Three of six catheterized females succumbed during the stress. The remaining rats fell into two groups in terms of their core temperature at the end of the stress period: Male uncatheterized rats had higher temperatures than rats in the other three groups. No relation was found between catheter patency and magnitude of hypothermia. Degree of gastric disease paralleled the core temperature findings in that the male uncatheterized rats had significantly fewer gastric erosions than the rats in the other three groups. Additionally, a robust effect of gender was found with uncatheterized females showing more hypothermia and more gastric disease than uncatheterized males. A subsequent experiment was conducted to evaluate whether anesthesia or wearing the protective spring was responsible in part for the sensitization seen. Here, the gender difference was less although females consistently averaged lower core temperatures after stress than did males. Despite similar core temperatures after stress, females that were prepared with the protective spring apparatus developed more gastric disease than female controls or similarly treated males. Thus, the additional sensitization exhibited by females in the first experiment may relate to the fact that both catheterization and the taping procedure were sensitizers while only catheterization was a sensitizer for males.  相似文献   
994.
Experiments 1 and 2 established children’s (mean age 3 years, 7 months) subject-relative and object-relative motion thresholds at 1°31.37′/sec and 1°9.33′/sec, respectively, speeds well above those found for adults. Experiment 3 established that preschoolers, like adults, attribute object-relative motion to the smaller of two objects, with the inducing properties of the larger stimulus greatest when it is surrounding rather than adjacent to a smaller stimulus. The inducing advantage of surroundedness was equivalent for a single-element square frame and a multielement six-dot frame.  相似文献   
995.
996.
A sample of delinquent and nondelinquent male adolescents was assessed with respect to locus of control and intellectual achievement responsibility. Data were also gathered concerning age, family size, birth order, socioeconomic status, race, and school grade. Results were subjected to a multivariate analysis and showed support for a multidimensional model of locus of control. There was no difference in expectancy of control for negative academic events between delinquents and nondelinquents. In general, birth order and delinquency were the two most important determinants of locus of control. Results are discussed in terms of previous literature on locus of control with particular consideration paid to expectations of control.  相似文献   
997.
This study assessed the role of adaptive versus maladaptive coping behaviors and personal characteristics in influencing the affective reactions of managers to four role stressors. Maladaptive coping was found to moderate the relationships of several role stressors with felt stress and job satisfaction. Maladaptive coping and trait anxiety also demonstrated independent additive effects on felt stress and job satisfaction over and above that of all four stressors.  相似文献   
998.
Three measures of chronic self-esteem, plus four measures developed to assess situational components of self-esteem (task-specific self-esteem and social self-esteem), were administered to 238 undergraduates at a large, urban university and a community college in the southeastern United States. Evidence for a composite construct of self-esteem was found. Results also indicate task-specific self-esteem correlates as high as .42 (p < .01) with chronic self-esteem and as high as .76 (p < .01) with social self-esteem. Task-specific self-esteem was found to be a better predictor of grade point average than chronic or social self-esteem. Suggestions are made for further research on the situational components of self-esteem to extend current findings.  相似文献   
999.
The authors recently proposed that adverse effects of material rewards on Wechsler subscale performance may be the result of a reward-produced developmental regression. The present study further explores that idea through an attempt to replicate earlier findings with adults and to extend the inquiry to children. Selected Wechsler subscales were administered to 32 subjects at each of three ages (5, 10, and 18 years) under either reward or nonreward conditions. Subscales were chosen to represent both algorithmic and heuristic types of tasks. Reward and nonreward groups (8 males and 8 females per group at each age) were matched initially on age and ability. For adults, consistent with earlier findings, reward had an adverse effect on performance on the heuristic subscales and tended to facilitate performance on the algorithmic subscales. However, rewards generally had no effect at the fourth-grade level and had a reverse effect at the nursery school level, i.e., rewards facilitated heuristic and hampered algorithmic performance. These findings appear to be more consistent with an explanation based on developmental regression than on any available alternative mechanism.  相似文献   
1000.
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