首页 | 官方网站   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   126094篇
  免费   1640篇
  国内免费   257篇
文化教育   127991篇
  2021年   989篇
  2020年   1698篇
  2019年   2610篇
  2018年   3163篇
  2017年   3418篇
  2016年   3444篇
  2015年   2361篇
  2014年   3232篇
  2013年   27342篇
  2012年   2473篇
  2011年   2851篇
  2010年   2417篇
  2009年   2667篇
  2008年   2493篇
  2007年   2245篇
  2006年   2472篇
  2005年   2416篇
  2004年   3104篇
  2003年   2379篇
  2002年   2217篇
  2001年   2157篇
  2000年   1820篇
  1999年   1675篇
  1998年   1482篇
  1997年   1536篇
  1996年   1700篇
  1995年   1471篇
  1994年   1482篇
  1993年   1476篇
  1992年   1578篇
  1991年   1483篇
  1990年   1465篇
  1989年   1399篇
  1988年   1259篇
  1987年   1195篇
  1986年   1214篇
  1985年   1487篇
  1984年   1328篇
  1983年   1328篇
  1982年   1270篇
  1981年   1197篇
  1980年   1186篇
  1979年   1311篇
  1978年   1229篇
  1977年   1141篇
  1976年   1028篇
  1975年   833篇
  1974年   832篇
  1973年   805篇
  1971年   666篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
This study investigated the basic cognitive skills soldiers must possess before entering the Army, skills that are needed for successful completion of entry-level training. Judgments of 126 instructors from 25 military occupational specialties were obtained on 129 candidate skills, which resulted in the identification of 55 basic skills. Factor analysis of these 55 skill items resulted in 11 interpretable factors. Mean scores on the factors were compared across factors and across Army training schools. The results of the study suggest that, for all occupational specialties studied, skills related to the learning process are as crucial as traditional academic skills for successful training course completion. These results have important implications for training for the Army as well as for industry.  相似文献   
102.
从语源上看,汉英相去甚远,两种语言最大的差异是汉字英词。汉语和英语分属汉藏和印欧语系。但汉英又同属曲折变化较少的分析性语言,也都不是典型的综合型语言。它们之间既有不同之处,也有共通的东西。本文研究的主要是差异性。  相似文献   
103.
Financing universities in times of increasing demands in all fields of public expenditure is a problem of nearly all European counnies not least because of the ongoing process of European integration. Comparing the different national systems of financing universities may be a means to foster cooperation and competition in a step by step growing network of universities in the European Community. This paper tries to give some insights into the German system; special considerotion is given to its federal structure and its implications for the universities' financthg system, because these problems may be of interest to other countries also. Of course this survey cannot be complete; details must be left to detailed information. The first part of the paper gives a survey of the higher education system in the Federal Republic of Gennany. The second part deals with the sources of funds, including the structure of mong streams to the universities. The third part refffs to the restrictions in using state money in the universities and the problems resulting; the fourth and final part concentrates on problems of the future, especially getring third party finds, and the diversifiation. of financing.  相似文献   
104.
105.
106.
目的探讨尿素酶型纤溶酶原激活物(urokinase-type plasminigen activator,uPA)、乙酰肝素酶(heparanase,HPA)在卵巢上皮癌和淋巴结转移癌中表达及其与肿瘤侵袭的关系。方法应用免疫组化SABC法,对65例卵巢上皮肿瘤手术标本进行uPA和HPA蛋白表达的测定。结果uPA、HPA在卵巢上皮癌中阳性表达率分别为66.7%、51.1%,其明显高于良性肿瘤及正常组织,有淋巴结转移的肿瘤的阳性表达率分别为78.1%、62.5%,无淋巴结转移的肿瘤阳性表达率分别为38.1%、23.1%,uPA和HPA高表达与卵巢癌侵袭和淋巴结转移关系密切(P<0.05)。uPA和HPA在卵巢癌中的表达无显著性差异(P>0.05)表达成正相关(r=0.724)。结论uPA和HPA蛋白的表达与卵巢癌的侵袭和转移有显著的相关性。  相似文献   
107.
    
There is an increasing interest in linking character education programs with social and academic outcomes. The Child Development Project (CDP) is a character education program that promotes academic and social growth in teachers and students. This theory-driven evaluation employed a quasi-experimental design with matched control schools. School personnel participated in an intensive professional development process to learn the CDP model. Performance measures included state-mandated achievement measures, teacher self-assessment reports, and student attitudes and outcomes. Results yielded support for the CDP model as a strategy to improve social and, if properly implemented, cognitive outcomes in students; the model also improved teacher self-assessment and provided information that may facilitate professional growth about school collegiality. Implications for policy and practice will be discussed.  相似文献   
108.
What legal issues may arise in setting content or performance standards? What precedents are relevant? What practices are defensible?  相似文献   
109.
Conclusion Computer-based career systems should be the focal point of popular, and effective career development initiatives which are of tremendous benefit to individuals. Such initiatives also have the potential to significantly reduce public expenditures and enhance the nation's competitive position internationally. The key lies in helping people understand that we can no longer afford to neglect the career development needs of Americans.I am most grateful for this opportunity to share my thoughts with you. I encourage you to promote the use of computer-based career systems by defining their benefits in economic terms. However, be sure you can prove your system does more than simply entertain its users, or leave them with extensive computer printouts.Phillip S. Jarvis is Manager, Careerware Research and Product Design, STM Systems Corp., Ottawa, Ontario, Canada and the author of CHOICES. This is the text of a paper presented to the Annual Conference of the Association of Computer-Based Systems for Career Information ((ACSCI) in St. Louis, Missouri on December 2, 1988.  相似文献   
110.
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-23

京公网安备 11010802026262号