全文获取类型
收费全文 | 23747篇 |
免费 | 336篇 |
国内免费 | 14篇 |
专业分类
教育 | 16914篇 |
科学研究 | 1934篇 |
各国文化 | 256篇 |
体育 | 2310篇 |
综合类 | 7篇 |
文化理论 | 218篇 |
信息传播 | 2458篇 |
出版年
2021年 | 238篇 |
2020年 | 367篇 |
2019年 | 542篇 |
2018年 | 746篇 |
2017年 | 678篇 |
2016年 | 676篇 |
2015年 | 407篇 |
2014年 | 538篇 |
2013年 | 4321篇 |
2012年 | 487篇 |
2011年 | 540篇 |
2010年 | 408篇 |
2009年 | 438篇 |
2008年 | 479篇 |
2007年 | 445篇 |
2006年 | 416篇 |
2005年 | 366篇 |
2004年 | 396篇 |
2003年 | 308篇 |
2002年 | 329篇 |
2001年 | 460篇 |
2000年 | 511篇 |
1999年 | 435篇 |
1998年 | 259篇 |
1997年 | 250篇 |
1996年 | 311篇 |
1995年 | 244篇 |
1994年 | 261篇 |
1993年 | 221篇 |
1992年 | 351篇 |
1991年 | 366篇 |
1990年 | 340篇 |
1989年 | 364篇 |
1988年 | 340篇 |
1987年 | 330篇 |
1986年 | 330篇 |
1985年 | 373篇 |
1984年 | 294篇 |
1983年 | 304篇 |
1982年 | 243篇 |
1981年 | 248篇 |
1980年 | 259篇 |
1979年 | 350篇 |
1978年 | 259篇 |
1977年 | 240篇 |
1976年 | 199篇 |
1975年 | 185篇 |
1974年 | 183篇 |
1973年 | 176篇 |
1971年 | 175篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
Textbook vetting and evaluation process intends to ensure that the materials provided are relevant, of the required quality, suitable ad would enhance learning efficiency and effectiveness. The paper investigates the role of publishers and Tanzania Institute of Education (TIE) in the textbooks vetting and evaluation process; examines factors used to vet, evaluate and approve primary and secondary school textbooks in Tanzania and proposes Strategies that would enhance the textbook vetting, evaluation and process. The study used a mixed method research design. Respondents were selected educational publishers; MoEVT, Baraza la Kiswahili Tanzania, TIE, and Publishers Association of Tanzania. Questionnaire and semi- structured interview were used to collect data which were analysed qualitatively and quantitatively. Major findings of the study were; textbooks vetting and evaluation process is not professionally conducted although standard criteria have been established; there is not well established roles among key players involved in the vetting and evaluation process leading to conflict of interest between TIE and the publishers. The study recommends establishing an independent professional evaluation board and a well-defined timetable and effective communication among various players; enacting a book policy and adopting a limited multiple-textbook publishing system. 相似文献
132.
This study replicated a previous research project addressing connections between family-of-origin communication and organizational dissent expression. We predicted that family communication patterns (FCPs), specifically conversation and conformity orientations, would predict upward, lateral, and displaced dissent. As in the original study, significant findings emerged for upward dissent and conformity orientation. This replication study indicated family type as an inconsistent predictor of expressed dissent. Contrary to the original study, we found no evidence to support a connection between pluralistic family types and upward dissent. Finally, as an extension of the original study we analyzed effects of FCPs on displaced dissent, finding an inverse association with conversation orientation. Implications for future research are discussed. 相似文献
133.
134.
Raymond J. Pingree Elizabeth Stoycheff Mingxiao Sui Jason T. Peifer 《Mass Communication and Society》2018,21(5):555-584
The mere perception that news has given certain problems more coverage can lead the audience to assume that those problems are more important. Given that the news media, at times, obsesses over relatively trivial matters, and given that the audience is increasingly able to filter media exposure, it is worth asking what happens when audience members perceive that recent media coverage has not emphasized any very important problems. In such cases, audience members might assume that any problems facing the nation must not be particularly important. We explicate this attitude of political complacency, test whether perceived media agendas lacking important problems can influence it, and explore whether complacency helps explain political disengagement. We also explore whether these effects generalize beyond news, to new media gatekeepers such as Twitter. Two experiments tested effects of a perceived absence of important problems in recent news or Twitter content. In the case of news, but not Twitter, this increased complacency in both studies. Study 2 added a no-exposure control and found that effects on complacency were driven by the cueing of nonproblem stories, not by the absence of problem story cues. Both studies validated complacency as a predictor of political disengagement. 相似文献
135.
136.
137.
138.
139.
Zhi Chen Jingfeng Li Tianzhong Li Taojian Fan Changle Meng Chaozhou Li Jianlong Kang Luxiao Chai Yabin Hao Yuxuan Tang Omar A Al-Hartomy Swelm Wageh Abdullah G Al-Sehemi Zhiguang Luo Jiangtian Yu Yonghong Shao Defa Li Shuai Feng William J Liu Yaqing He Xiaopeng Ma Zhongjian Xie Han Zhang 《国家科学评论(英文版)》2022,9(8)
The outbreak of the COVID-19 pandemic was partially due to the challenge of identifying asymptomatic and presymptomatic carriers of the virus, and thus highlights a strong motivation for diagnostics with high sensitivity that can be rapidly deployed. On the other hand, several concerning SARS-CoV-2 variants, including Omicron, are required to be identified as soon as the samples are identified as ‘positive’. Unfortunately, a traditional PCR test does not allow their specific identification. Herein, for the first time, we have developed MOPCS (Methodologies of Photonic CRISPR Sensing), which combines an optical sensing technology-surface plasmon resonance (SPR) with the ‘gene scissors’ clustered regularly interspaced short palindromic repeat (CRISPR) technique to achieve both high sensitivity and specificity when it comes to measurement of viral variants. MOPCS is a low-cost, CRISPR/Cas12a-system-empowered SPR gene-detecting platform that can analyze viral RNA, without the need for amplification, within 38 min from sample input to results output, and achieve a limit of detection of 15 fM. MOPCS achieves a highly sensitive analysis of SARS-CoV-2, and mutations appear in variants B.1.617.2 (Delta), B.1.1.529 (Omicron) and BA.1 (a subtype of Omicron). This platform was also used to analyze some recently collected patient samples from a local outbreak in China, identified by the Centers for Disease Control and Prevention. This innovative CRISPR-empowered SPR platform will further contribute to the fast, sensitive and accurate detection of target nucleic acid sequences with single-base mutations. 相似文献
140.