全文获取类型
收费全文 | 254篇 |
免费 | 0篇 |
专业分类
教育 | 155篇 |
科学研究 | 21篇 |
各国文化 | 4篇 |
体育 | 48篇 |
文化理论 | 8篇 |
信息传播 | 18篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2021年 | 8篇 |
2020年 | 8篇 |
2019年 | 17篇 |
2018年 | 16篇 |
2017年 | 17篇 |
2016年 | 17篇 |
2015年 | 8篇 |
2014年 | 12篇 |
2013年 | 52篇 |
2012年 | 9篇 |
2011年 | 7篇 |
2010年 | 9篇 |
2009年 | 7篇 |
2008年 | 6篇 |
2007年 | 7篇 |
2006年 | 7篇 |
2005年 | 6篇 |
2004年 | 7篇 |
2003年 | 5篇 |
2001年 | 2篇 |
1999年 | 6篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1982年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有254条查询结果,搜索用时 15 毫秒
211.
Mohamed Oujja Esther Rebollar Marta Castillejo Concepcin Domingo Concepcin Cirujano Fernando Guerra-Librero 《Journal of Cultural Heritage》2005,6(4):321-327
Laser cleaning has been used to restore the soiled terracotta statues and decorations of the tympanum of the portal of Palos of the Cathedral of Seville in Spain. A simultaneous laboratory study performed on a representative sample helped to identify the optimum laser conditions to remove the dark soiling layer produced by air pollution. It was found that irradiation at 1064 nm with a Q-switched Nd:YAG laser was more effective than the harmonic wavelengths of 532 or 266 nm. LIBS and Raman microscopy gave information on the composition of terracotta and identified the presence of a protective layer made of gypsum and calcite. As detected by Raman spectroscopy, laser irradiation caused the elimination of the carbon component of the soiling layer and the appearance of an anhydrite component in the laser irradiated gypsum layer applied over the terracotta substrate for protective purposes. Local heating of the surface caused by laser irradiation at 1064 nm, the laser wavelength used for restoration of the portal, might be responsible for a process of partial dehydration of gypsum into anhydrite. 相似文献
212.
213.
214.
Joaquin Sanchis-Moysi Cecilia Dorado Fernando Idoate Juan J. González-Henríquez Jose A. Serrano-Sanchez Jose A. L. Calbet 《European Journal of Sport Science》2016,16(7):780-786
It is generally accepted that preadolescents have a limited capacity to develop muscle hypertrophy in response to exercise compared with older populations; however, studies are scarce and conflicting. The main aim of the present study was to assess if playing tennis is associated with the hypertrophy of dominant pectoralis muscles (PM) in professional (PRO) and in prepubescent tennis players (PRE). A secondary aim was to assess if the degree of asymmetry of PM is greater in PRO than PRE. The volume of PM of both sides was determined using magnetic resonance imaging in 8 male PRO (21.9 years), 6 male PRE (11 years, Tanner 1–2) and 12 male non-active controls (6 adults: 23.5 years; and 6 prepubescents: 10.7 years, Tanner 1–2). PRO and PRE had 15 and 30% greater volume, respectively, in the dominant than in the contralateral PM (P?.01). No significant side-to-side differences in PM volume were observed in the non-active controls (3%, P?=?.34 in adults and 5%, P?=?.17 in children). The degree of side-to-side asymmetry in PM volume was greater in PRE than in PRO (P?.05). In conclusion, tennis practice is associated with marked hypertrophy of dominant PM in tennis players, even at prepubertal age, whilst non-active age-matched control subjects display similar volumes in both sides. The larger asymmetry observed in PRE than in PRO may indicate a greater relative loading in the children or increased contralateral hypertrophy in the professionals. This study demonstrates that prepubertal children respond with marked hypertrophy to loading by tennis. 相似文献
215.
Fernando Rodriguez Emilio Duran Juan P. Vargas Blas Torres Cosme Salas 《Learning & behavior》1994,22(4):409-420
Goldfish were trained to obtain food in a four-arm maze placed in a room with relevant spatial cues. Four experimental conditions were run: allocentric, egocentric, egocentric + allocentric, and control. Relative to controls, all groups were able to solve the different tasks with high accuracy after 1 week of training. Subsequent transfer tests revealed place and response strategies for allocentric and egocentric groups, respectively, and both types of strategies for the ego-allocentric group. Moreover, the allocentric group showed the capacity to choose the appropriate trajectory toward the goal, even from novel starting points, presumably by using the distal cues as a whole. The results suggest that, in addition to using egocentric strategies, goldfish are able to solve spatial tasks on the basis of allocentric frames of reference and to build complex spatial cognitive representations of their environment. 相似文献
216.
Although well-renowned universities attempt to differentiate themselves from other universities, little research has been undertaken on the principal themes involved in the concept of the world-class university (WCU) as presented in speeches by members of WCUs. These discourses are a key tool in universities’ attempt to shape the competitive framework of higher education through legitimacy. We study the presidents’ discourses from 100 leading universities to identify the themes and emergent discourse of these universities’ communities. Applying topic modeling methodology to the speeches’ corpus, we find seven communities (Worldwide-the four regions, American-from different states, Flagship, Education concerned, Some Chinese universities, Central European universities and Challengers) and four main themes arising from WCUs’ discourses (Research universities within international rankings, Stakeholders and leadership, Mission and values, and Education). Our preliminary findings suggest that leading universities are working to adopt the WCU label based on their salient characteristics. 相似文献
217.
Fernando Flores-Camacho Leticia Gallegos-Cázares Andoni Garritz Alejandra García-Franco 《Science & Education》2007,16(7-8):775-800
The notion of incommensurability has provided a rationality criterion for the development of scientific theories, as well
as some insight into theories developed by students while learning science. However, the relationship between the multiple
models held by students and incommensurability requires further discussion. We present the results of empirical work that
investigated the multiple models of the structure of the matter held by university students and we analyze these results using
the notion of incommensurability. We also point out implications in the construction of students’ scientific models as they
move forward in their careers. 相似文献
218.
Luis Fernando Macías Bruce Anthony Collet 《Diaspora, Indigenous, and Minority Education》2016,10(3):169-181
This research examines the impact of parental deportation on Latino/a adolescents’ postsecondary aspirations. Based on interviews with students, their families, and site observations, the study finds that for some adolescents who held college aspirations prior to the deportation, this type of abrupt parental removal negatively affects their perception of safety and stability in their home and school environments (i.e., microsystem) (Bronfenbrenner, 2005). Where this vulnerability is not countered with emotional, economic, and institutional support, it can hinder their development of the social capital (Coleman, 1988; Stanton-Salazar, 2001) that would be conducive to their higher educational aspirations. 相似文献
219.
The main aim of our study was to find out the effect of several lexical and sublexical variables (lexical category, lexical frequency, syllabic structure, and word length) in the acquisition of reading in a transparent language such as Spanish. The second goal of our study was the comparison of the effect of these variables in normal and poor Spanish readers. One hundred and forty children (aged between 6 and 12), twenty of whom were poor readers, were tested using a reading test of 306 items in which we balanced all the variables. The dependent variable was the percentage of correct responses in a decontextualized word reading test. Our results showed that all the above mentioned variables produced a significant effect on the number of errors made by the children. This pattern of results suggests no difference between the processes involved in the reading acquisition of Spanish and those implicated in deep orthographies such as English. Our results also showed no qualitative differences between normal and poor readers. The four variables studied showed the same behaviour in their effect on reading performance for both normal and poor readers, indicating that poor readers also use both the lexical and the phonological route. Our data suggest the universality of the dual route model, independent of the transparency or opaqueness of the different alphabetical languages. 相似文献
220.
This study contributes empirical evidence regarding communicative functions in the pre-grammatical period. The aim was to explore these functions in child-adult dyadic interactions during what in language acquisition research has been called the two-word period. The study draws from the data corpus of a child 19–29 months old and the system of sign categories (gestures, non-verbal vocalizations, verbal vocalizations, uni- and bimodal compositions) developed by Rodríguez & Español. In order to study the communicative functions in this period, an observational code was developed in accordance with Strauss and Corbin’s Constant Comparative Method, which is suitable for encompassing the entire repertoire of a child’s sign use. The study in general allowed some functions absent in adult communication to be identified, and the qualitative analysis in particular revealed a use of semiotic resources that supports the idea of a cognitive processing structure common to gesture and word. 相似文献