全文获取类型
收费全文 | 4200篇 |
免费 | 58篇 |
国内免费 | 1篇 |
专业分类
教育 | 3302篇 |
科学研究 | 152篇 |
各国文化 | 44篇 |
体育 | 425篇 |
综合类 | 2篇 |
文化理论 | 34篇 |
信息传播 | 300篇 |
出版年
2022年 | 18篇 |
2021年 | 22篇 |
2020年 | 38篇 |
2019年 | 79篇 |
2018年 | 87篇 |
2017年 | 110篇 |
2016年 | 86篇 |
2015年 | 70篇 |
2014年 | 140篇 |
2013年 | 1031篇 |
2012年 | 125篇 |
2011年 | 129篇 |
2010年 | 123篇 |
2009年 | 135篇 |
2008年 | 96篇 |
2007年 | 94篇 |
2006年 | 96篇 |
2005年 | 59篇 |
2004年 | 44篇 |
2003年 | 49篇 |
2002年 | 54篇 |
2001年 | 45篇 |
2000年 | 73篇 |
1999年 | 55篇 |
1998年 | 42篇 |
1997年 | 34篇 |
1996年 | 62篇 |
1995年 | 115篇 |
1994年 | 65篇 |
1993年 | 81篇 |
1992年 | 96篇 |
1991年 | 89篇 |
1990年 | 67篇 |
1989年 | 38篇 |
1988年 | 30篇 |
1987年 | 31篇 |
1986年 | 24篇 |
1985年 | 30篇 |
1984年 | 26篇 |
1983年 | 18篇 |
1982年 | 30篇 |
1981年 | 32篇 |
1980年 | 34篇 |
1979年 | 74篇 |
1978年 | 59篇 |
1977年 | 53篇 |
1976年 | 37篇 |
1975年 | 28篇 |
1974年 | 28篇 |
1972年 | 14篇 |
排序方式: 共有4259条查询结果,搜索用时 15 毫秒
91.
Because access to new technologies is unequally distributed, there has been considerable debate about the growing gap between the so‐called information‐rich and information‐poor. Such concerns have led to high‐profile information technology policy initiatives in many countries. In Australia, in an attempt to ‘redress the balance between the information rich and poor’ by providing ‘equal access to the World Wide Web’ (Virtual Communities, 2002), the Australian Council of Trade Unions, Virtual Communities (a computer/software distributor) and Primus (an Internet provider) in late 1999 formed an alliance to offer relatively inexpensive computer and Internet access to union members in order to make ‘technology affordable for all Australians’ (Virtual Communities, 2002). In this paper, we examine four families, one of which had long‐term Information and Communication Technologies (ICT) access, and three of which took advantage of the Virtual Communities offer to get home computer and Internet access for the first time. We examine their engagement with ICT and suggest that previously disadvantaged family members are not particularly advantaged by their access to ICT. 相似文献
92.
93.
Fourteen behavioral measures were ranked according to their ability to differentiate performances of a wild population of mice from three domestic inbred strains. These “wildness” rankings were then analyzed for their ability to predict genetic and Genotype by Environment interactions. Genetic parameters were derived from analysis of three inbred domestic strains and their three hybrid crosses via the diallel technique of genetic analysis. Genotype by Environment interactions were assessed both as mean differences in stock performances resulting from rearing in a laboratory vs naturalistic environment and as differences in environmental variability within stock genotypes. Behavioral characters ranking high on “wildness” failed to demonstrate any unitary pattern of Genotype by Environment interactions. The diallel genetic analysis revealed many examples of additive variation but relatively few examples of dominant variation. An extremely wide range of interactions occurred between genotype and rearing environments, with “wildness” and “developmental homeostasis” concepts both failing to account for all the observed interactions. 相似文献
94.
Expanding and diversifying the STEM (science, technology, engineering, and mathematics) workforce is a national priority. The National Science Foundation is investing efforts at post secondary education institutions to engage individuals who have been historically underrepresented in STEM. This paper investigated the use of strategies to broaden participation in STEM by grantees of NSF’s Advanced Technological Education (ATE), who are primarily located at 2-year colleges. The ATE program focuses on developing and improving technician training programs to prepare students for employment in fields that rely on advanced technologiessuch as nanotechnology, photonics, and mechatronics. A survey, conducted annually by the authors of this study, was used to collect data from ATE grantees on their use and perceptions of strategies to broaden participation in STEM. The findings showed that strategies related to motivation and access to enhance recruitment are more widely used then strategies that improve retention. Respondents identified strategies related to providing financial assistance, mentoring, and conducting outreach activities as the most effective for reaching and engaging underrepresented minority students in academic programs. Despite these perceptions, these strategies seem to be underutilized among this group. 相似文献
95.
The goals of this research were to explore the current literature regarding associations between psychological stress and adverse fetal outcome, associations between aerobic exercise and psychological stress reduction, and associations between aerobic exercise and fetal outcome. The published studies that were located provide evidence of the following: 1) Stress reactivity increases physiologically during pregnancy, 2) pregnant women may experience additional stressors that are usually not experienced in a nonpregnant state, 3) psychological stress in pregnancy is associated with adverse fetal outcome, 4) exercise can be a method of stress reduction, 5) exercise in pregnancy is not associated with adverse fetal outcome, and 6) exercise in pregnancy may provide benefit to the fetus. Data were analyzed from an original study and associations were reported between psychological stress-management activities and participation in aquatic aerobic exercise classes. No reports were available investigating an exercise-induced reduction in psychological stress with fetal outcome. 相似文献
96.
The primary purpose of this research was to examine the construct validity of the Child Abuse Potential Inventory by comparing maltreating and high-risk parents' CAP Inventory abuse scores to their behavior during interactions with their children. A second purpose was to determine the degree to which CAP Inventory scores and parenting behavior were related to several known correlates of abuse, as measured by parent and teacher reports. Participants (n = 41) included abusive and high-risk parents and their children referred to a treatment group. Correlational analyses revealed that CAP Inventory scores and observed parenting style yielded highly related findings, supporting construct validity of the CAP Inventory. However, the CAP Inventory and observed behavior index showed a different pattern of relationships to the risk correlates. Implications for assessment of risk status are discussed and recommendations are provided for continued research. 相似文献
97.
Prof. Dr. Andreas Hartinger Thilo Kleickmann Dr. Birgit Hawelka 《Zeitschrift für Erziehungswissenschaft》2006,9(1):110-126
Es gibt einige Hinweise darauf, dass Vorstellungen vom Lehren und Lernen sowohl für das Handeln der Lehrkr?fte im Unterricht
als auch für Zielkriterien auf der Ebene der Schüler eine Rolle spielen. Dabei gelten konstruktivistisch orientierte Sichtweisen
als besonders günstig. Empirische Untersuchungen dazu gibt es jedoch bislang nur auf einzelne fachdidaktische Inhaltsbereiche
bezogen. In der vorliegenden Studie werden konstruktivistisch orientierte Lehrereinstellungen mit Merkmalen des Unterrichts
(?ffnung des Unterrichts im Hinblick auf Entscheidungsm?glichkeiten für Schüler/-innen und Strukturierung des Unterrichts)
sowie mit Einsch?tzungen der Schüler/-innen (Selbstbestimmungsempfinden und Interessantheit des Unterrichts) in Beziehung
gesetzt. Die Ergebnisse best?tigen die Theorie: In den Klassen der Lehrer/-innen mit überwiegend konstruktivistischen Vorstellungen
von Lernen und Lehren gibt es mehr Freir?ume, ohne dass der Unterricht weniger strukturiert abl?uft. Zudem empfinden sich
die Schüler/-innen als selbstbestimmter und sch?tzen den Unterricht als interes-santer ein. 相似文献
98.
Prof. Dr. Michael Dowling 《科研管理》2004,25(Z1):106-111
通过对美国及德国的十多年研究表明,对于创新及合作网络的投资有利于促进高技术行业企业不断进步和发展.这些高技术行业包括电信、电脑设备及生物工艺的行业.研究表明政府政策在促进竞争及支持地区合作网络发展中起到了极其重要的作用. 相似文献
99.
This paper examines the meaning of context in relation to ontology based query expansion and contains a review of query expansion approaches. The various query expansion approaches include relevance feedback, corpus dependent knowledge models and corpus independent knowledge models. Case studies detailing query expansion using domain-specific and domain-independent ontologies are also included. The penultimate section attempts to synthesise the information obtained from the review and provide success factors in using an ontology for query expansion. Finally the area of further research in applying context from an ontology to query expansion within a newswire domain is described. 相似文献
100.
Jackson R Baird W Davis-Reynolds L Smith C Blackburn S Allsebrook J 《Health information and libraries journal》2007,24(2):95-102
OBJECTIVES: The objectives of this work were to identify the sources of information currently received, information-seeking behaviours, information requirements and preferences for future information provision amongst health and social care professionals providing care to children with health care needs. METHODS: Data were collected using a cross-sectional postal questionnaire survey. RESULTS: A wide range of information resources was reported as being available to professionals. However, a large proportion of respondents found it necessary to perform additional searches for information, suggesting that current resources were not satisfying their needs. The majority of professionals reported a preference for electronic formats, whilst a smaller proportion preferred hard copy materials. Participants promoted the use of informal networks as a means of support and exchange of information. CONCLUSION: Supplementing the information that is provided in electronic and hard copy formats, by enhancing informal networks, may be the most effective way of meeting the information needs of this group of professionals. 相似文献