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   18682篇
  免费   878篇
  国内免费   717篇
  2021年   184篇
  2020年   221篇
  2019年   292篇
  2018年   359篇
  2017年   335篇
  2016年   333篇
  2015年   247篇
  2014年   333篇
  2013年   1489篇
  2012年   595篇
  2011年   705篇
  2010年   472篇
  2009年   502篇
  2008年   618篇
  2007年   734篇
  2006年   696篇
  2005年   586篇
  2004年   532篇
  2003年   452篇
  2002年   399篇
  2001年   505篇
  2000年   550篇
  1999年   404篇
  1998年   239篇
  1997年   186篇
  1996年   192篇
  1995年   190篇
  1994年   166篇
  1992年   285篇
  1991年   292篇
  1990年   305篇
  1989年   285篇
  1988年   276篇
  1987年   238篇
  1986年   256篇
  1985年   268篇
  1984年   201篇
  1983年   214篇
  1982年   164篇
  1979年   251篇
  1978年   216篇
  1975年   215篇
  1974年   242篇
  1973年   268篇
  1972年   225篇
  1971年   210篇
  1969年   195篇
  1968年   248篇
  1967年   239篇
  1966年   209篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Sun  Juan  Zhang  Qiang 《Cognitive processing》2021,22(2):171-181
Cognitive Processing - Mandarin speakers, similar to speakers of most other languages around the world, tend to conceptualize time in terms of space. However, it has been supposed that Mandarin...  相似文献   
992.
993.
基于付出回报失衡模型,考察了高校青年教师的付出回报失衡与焦虑的关系。对336名高校青年教师进行了多时间点调查。结果显示:(1)付出回报失衡对高校青年教师的焦虑有显著正向预测作用;(2)付出回报失衡通过心理契约破裂间接影响高校青年教师的焦虑;(3)相较于低过度承诺教师,高过度承诺教师的付出回报失衡经由心理契约破裂对焦虑的影响更为突出。研究结果揭示了付出回报失衡对焦虑影响的过程机制和边界条件,对高校青年教师工作焦虑的改善有一定启示。  相似文献   
994.
995.
人类的生存繁衍依赖于人们之间的相互合作,合作与冲突行为的研究近年来成为心理学的研究热点。本研究通过实验程序操纵Chicken Game中博弈同伴的特点,考察个体在社会困境中面对不同特点同伴时的合作行为。结果发现:(1)同伴道义论组和功利论组总和解率没有显著差异,同伴竞争组和合作组的总和解率也没有显著差异。(2)在与道义论以及合作型的同伴互动时,个体的行为没有明显受到上次博弈反馈的影响。(3)当同伴为功利论时,相比于上次博弈个体选择和解而同伴选择进攻,双方都选择和解时个体在当前博弈中更倾向于和解;(4)在同伴竞争组中,相比于上次博弈个体选择进攻而同伴选择和解,双方都选择和解时被试在当前博弈中会更倾向于和解。实验结果表明个体在博弈任务中会受到同伴特点的影响,并且同伴在博弈中的行为特点的影响更为显著。本研究从同伴特点来考察个体的合作行为,揭示了影响个体博弈行为的一种因素。  相似文献   
996.
997.
Background/Objective: This study explored the association between active school travel (AST) and suicide attempts among adolescents in low- and middle-income countries (LMICs). Method: We used the data from the Global School-based Health Survey, including 127,097 adolescents aged 13-17 years from 34 LMICs. A self-reported survey was used to collect data on AST and suicide attempts as well as some variables. Multivariable logistic regression was performed to assess the association between AST and suicide attempts. A meta-analysis with random effects was undertaken to identify the difference in the association between AST and suicide attempts. Results: Across all the adolescents, the prevalence of AST was 37% and the prevalence of suicide attempts was 11.60%. Adolescents who engaged in AST were less likely to have suicide attempts irrespective of gender. The country-wise analysis indicated a large inconsistency in the association between AST and suicide attempt across the countries. Conclusions: AST would appear to be a protective factor for reducing suicide attempts among adolescents. However, the association between AST and suicide attempts varied greatly across the countries. Future studies should confirm the association between AST and suicide attempts.  相似文献   
998.
Aggressive and sexual behavior was studied in 5-minute paired encounters between testosterone-treated castrated boars and estrogen-treated ovariectomized gilts. The boars were either 15 kg heavier (N = 6), or lighter (N = 6), than the gilts (N = 8). Tests were carried out over a 4-week period, during which time each boar was paired once with each gilt; the procedure was replicated over a further 4 weeks. Gilts usually initiated the aggression, especially in the first 4-week period; however, the degree of aggression was positively correlated with body size, irrespective of sex. Aggression was reduced in the second 4-week period in both sexes in tests with large, but not with small, boars. Large boars were more sexually active than small boars, and their sexual performance improved markedly with time, unlike that of the small boars. Champing was positively correlated with aggression duration in pigs of both sexes, and salivation was seen more often in boars than gilts.  相似文献   
999.
Female rats, chronically treated with Testosterone Propionate (TP), were injected with Fluprazine (DU 27716) or saline and tested for social aggression, masculine and feminine sexual behavior. Fluprazine-treated females were less aggressive than saline-treated females, as indicated by a shift from offensive to less offensive parameters of aggression. At the same time, mounting in Fluprazine-treated females was almost totally abolished, both in aggression tests and in tests for sexual behavior. Feminine sexual responses increased during aggressive encounters but were slightly inhibited when females were confronted with sexually active males. Females treated with Fluprazine and tested for mounting with a receptive female showed a substantial increase of offensive aggression directed at the receptive stimulus female. It is concluded that Fluprazine does not selectively inhibit offensive aggression in TP-treated female rats.  相似文献   
1000.
Aggressive and sexual behaviour was studied in 5-min paired encounters between castrated prepubertal boars (N = 14) and normal (N = 2) or bulbectomized (N = 2) oestrogen-treated ovariectomized gilts. The boars were made sexually active by treatment with 17β-oestradiol + 5α-dihydrotestosterone. Half of the boars were sprayed on the snout with a solution containing a mixture of the boar pheromones 3α-androstenol and 5α-androstenone immediately before testing, and the remainder were treated with the vehicle solution. Aggression was almost always initiated by the gilts, and neither bulbectomy nor pheromone treatment of the boars reduced its occurrence. The results suggest that the display of aggression by gilts towards boars of similar body size is unlikely to be suppressed by the steroidal pheromones present in boar saliva.  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