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   780篇
  免费   3篇
  国内免费   5篇
教育   383篇
科学研究   109篇
各国文化   3篇
体育   220篇
综合类   5篇
文化理论   1篇
信息传播   67篇
  2024年   2篇
  2022年   2篇
  2021年   4篇
  2018年   2篇
  2016年   3篇
  2015年   2篇
  2014年   6篇
  2013年   5篇
  2012年   57篇
  2011年   109篇
  2010年   28篇
  2009年   5篇
  2008年   56篇
  2007年   77篇
  2006年   58篇
  2005年   36篇
  2004年   34篇
  2003年   49篇
  2002年   28篇
  2001年   30篇
  2000年   32篇
  1999年   19篇
  1998年   5篇
  1997年   4篇
  1996年   5篇
  1995年   3篇
  1994年   6篇
  1993年   5篇
  1992年   10篇
  1991年   9篇
  1990年   10篇
  1989年   11篇
  1988年   9篇
  1987年   6篇
  1986年   8篇
  1985年   6篇
  1984年   6篇
  1983年   10篇
  1982年   5篇
  1981年   5篇
  1980年   3篇
  1978年   2篇
  1975年   2篇
  1959年   2篇
  1958年   2篇
  1954年   1篇
  1950年   1篇
  1947年   1篇
  1942年   1篇
  1926年   1篇
排序方式: 共有788条查询结果,搜索用时 15 毫秒
11.
Archaeologists announce discovery of tools and spear points in South Africa that may be 70, 000 years old.  相似文献   
12.
13.
北太平洋巨型章鱼是170余种巨型章鱼中的一种。人们曾经误把它们看成为海怪,实际上,它们性格平和,并不像古老传说描述的那样会攻击船只。  相似文献   
14.
Hearing loss during the critical period for language acquisition restricts spoken language input. This input limitation, in turn, may hamper syntactic development. This study examined the comprehension, production, and repetition of Wh-questions in deaf or hard-of-hearing (DHH) children. The participants were 11 orally trained Hebrew-speaking children aged 9.1-12.4 with moderate-to-profound hearing loss from birth, who consistently used hearing aids or cochlear implants and who had difficulties understanding relative clauses. Experiment 1 tested the comprehension of Wh-questions using a picture selection task, comparing subject with object questions and who- with which-questions; Experiment 2 tested the production of subject and object who-questions using an elicitation task; and Experiment 3 tested the repetition of Wh-questions and other structures derived by Wh-movement. All the DHH participants showed difficulty in the comprehension, production, and repetition of object questions, and their performance was significantly below that of hearing children. In contrast, they repeated embedded sentences without movement well, indicating that their deficit is in syntactic movement rather than embedding or the CP node in the syntactic tree. The results provide additional evidence that DHH children have difficulties with Wh-movement and emphasize that Wh-questions, which are crucial for communication, can be severely impaired in these children.  相似文献   
15.
OBJECTIVE: The aim of this study was to examine preschoolers' perceptions of maternal discipline's unfairness. The participants' gender, age, SES, family intactness and sibship size were examined for their possible relevance to such perceptions. METHOD: Five vignettes, describing forms of discipline the literature suggests constitute psychological maltreatment, were presented to 57 preschoolers (27 boys and 30 girls). They included excessive withdrawal of privileges, withdrawal of entertainment, differential treatment of siblings, threatening power assertion, and public humiliation. The children had to decide on the fairness or unfairness of each vignette in which a child was disciplined in each of these ways by his/her mother. They were then asked to offer an explanation for each of their choices. RESULTS: Of the five forms of discipline employed in the vignettes, children judged differential treatment of siblings as more unfair than either power assertion (threatening spanking), or public humiliation. No differences were found for withdrawal of privileges or entertainment. Of the various predictor variables employed, preschoolers from smaller families were more likely to judge threatening to spank as unfair. As well, compared to boys, girls and children from larger families were more likely to judge differential treatment as unfair. Age, SES, and family intactness had no effect on discipline judgements likely because of their limited range. CONCLUSIONS: The findings suggest that preschoolers can offer views on the fairness or unfairness of parental disciplinary practices, and can differentiate among them. Further, not all forms of parental discipline were viewed by preschoolers as unfair. Yet it has to be appreciated that the vignettes employed here were adapted for younger children, hence they may not have appeared as negative as in studies involving older children and adults.  相似文献   
16.
In the Netherlands, as in most other European countries, closed captions for the deaf summarize texts rather than render them verbatim. Caption editors argue that in this way television viewers have enough time to both read the text and watch the program. They also claim that the meaning of the original message is properly conveyed. However, many deaf people demand verbatim subtitles so that they have full access to all original information. They claim that vital information is withheld from them as a result of the summarizing process. Linguistic research was conducted in order (a) to identify the type of information that is left out of captioned texts and (b) to determine the effects of nonverbatim captioning on the meaning of the text. The differences between spoken and captioned texts were analyzed on the basis of on a model of coherence relations in discourse. One prominent finding is that summarizing affects coherence relations, making them less explicit and altering the implied meaning.  相似文献   
17.
Relations between self-reported parental reactions to children's negative emotions (PNRs) and children's socially appropriate/problem behavior and negative emotionality were examined longitudinally. Evidence was consistent with the conclusion that relations between children's externalizing (but not internalizing) emotion and parental punitive reactions to children's negative emotions are bidirectional. Reports of PNRs generally were correlated with low quality of social functioning. In structural models, mother-reported problem behavior at ages 10-12 was at least marginally predicted from mother-reported problem behavior, children's regulation, and parental punitive or distress reactions. Moreover, parental distress and punitive reactions at ages 6-8 predicted reports of children's regulation at ages 8-10, and regulation predicted parental punitive reactions at ages 10-12. Father reports of problem behavior at ages 10-12 were predicted by earlier problem behavior and parental distress or punitive reactions; some of the relations between regulation and parental reactions were similar to those in the models for mother-reported problem behavior. Parental perceptions of their reactions were substantially correlated over 6 years. Some nonsupportive reactions declined in the early to mid-school years, but all increased into late childhood/early adolescence.  相似文献   
18.
The present paper is divided into eight sections:introduction,the global diffusion of English,perceptions of the new varieties,the issue of intelligibility,features that cause unintelligibility,need for a broader pragmatics,and pedagogical impli- cations,and conclusion,followed by the references.Not surprisingly,the global spread of English has generated varying perspec- tives on the nature and functions of its acculturated varieties.Broadly speaking,the debate has divided scholars into two camps holding diametrically opposing views on the multiple versions of English.On the one hand,some scholars view variations as symp- toms of linguistic degeneration and deterioration;on the other hand,some scholars legitimize them as inevitable manifestations ne- cessitated by the demands of the new cultural contexts.The normative view of the former camp stems,at least partly,from the problems the new forms of English pose in terms of international intelligibility.It is in this context that the paper examines the traditional,one-sided,native speaker-centred idea of intelligibility and the recent two-sided view of intelligibility that places the onus on both the native speaker and the non-native speaker.The argument of the latter camp is based on the premise that the new varieties require a broader pragmatic framework,because universal pragmatics is inadequate to describe them satisfactorily. Thus,the camp advocates a need for a language specific pragmatics,and a comparative pragmatics,in addition to the traditional universal pragmatics.Logically,the debate on phonological,lexical,grammatical,and discourse structure variations,and their le- gitimacy has prompted English language teaching specialists to have a fresh look at the goals and objectives of teaching English in the countries of the outer and expanding circles,and accordingly prioritize the teaching of national and regional varieties over that of the so-called native varieties.Thus,the paradigms of independence and centrality of the new varieties are replacing the paradigms of their dependence and marginality.  相似文献   
19.
生命科学史     
恩培多克勒、希波克拉底、盖仑,与今天科学家能够在分子水平上探索生命的奥秘相比,他们显得有点笨拙.然而,他们却毫无疑问的应该被称作科学的先驱.对于大多数学习生物的人来说,1953年可以算作生物学的一个里程碑,这一年,沃森和克里克首次揭示出了DNA的分子结构,这是对于生命最核心问题的发现.  相似文献   
20.
Lipids changes in liver cancer   总被引:9,自引:1,他引:8  
Liver is one of the most important organs in energy metabolism. Most plasma apolipoproteins and endogenous lipids and lipoproteins are synthesized in the liver. It depends on the integrity of liver cellular function, which ensures homeostasis of lipid and lipoprotein metabolism. When liver cancer occurs, these processes are impaired and the plasma lipid and lipoprotein patterns may be changed. Liver cancer is the fifth common malignant tumor worldwide, and is closely related to the infections of hepatitis B virus (HBV) and hepatitis C virus (HCV). HBV and HCV infections are quite common in China and other Southeast Asian countries. In addition, liver cancer is often followed by a procession of chronic hepatitis or cirrhosis, so that hepatic function is damaged obviously on these bases, which may significantly influence lipid and lipoprotein metabolism in vivo. In this review we summarize the clinical significance of lipid and lipoprotein metabolism under liver cancer.  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