全文获取类型
收费全文 | 864篇 |
免费 | 21篇 |
专业分类
教育 | 586篇 |
科学研究 | 85篇 |
各国文化 | 12篇 |
体育 | 114篇 |
文化理论 | 22篇 |
信息传播 | 66篇 |
出版年
2023年 | 7篇 |
2022年 | 11篇 |
2021年 | 14篇 |
2020年 | 20篇 |
2019年 | 36篇 |
2018年 | 35篇 |
2017年 | 56篇 |
2016年 | 51篇 |
2015年 | 32篇 |
2014年 | 39篇 |
2013年 | 163篇 |
2012年 | 30篇 |
2011年 | 26篇 |
2010年 | 37篇 |
2009年 | 27篇 |
2008年 | 41篇 |
2007年 | 19篇 |
2006年 | 22篇 |
2005年 | 21篇 |
2004年 | 23篇 |
2003年 | 16篇 |
2002年 | 21篇 |
2001年 | 10篇 |
2000年 | 9篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1997年 | 6篇 |
1996年 | 7篇 |
1995年 | 5篇 |
1994年 | 6篇 |
1993年 | 6篇 |
1992年 | 9篇 |
1991年 | 7篇 |
1989年 | 8篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1982年 | 4篇 |
1980年 | 2篇 |
1978年 | 4篇 |
1974年 | 3篇 |
1973年 | 2篇 |
1969年 | 2篇 |
1965年 | 2篇 |
1957年 | 3篇 |
1944年 | 3篇 |
1866年 | 1篇 |
1860年 | 1篇 |
排序方式: 共有885条查询结果,搜索用时 31 毫秒
21.
Rajiah Simon 《Resonance》2002,7(2):20-25
K S Krishnan discovered in 1948 that the sum over samples of a band-limited function gives the value of the integral of the function exactly, provided the sampling interval does not exceed a threshold value. This result of Krishnan is shown to be equivalent to the Shannon sampling theorem. 相似文献
22.
23.
24.
25.
Increasing numbers of children are being born through egg donation and thus do not share a genetic relationship with their mother. Parent–infant relationship quality was examined in 85 egg donation families and a comparison group of 65 in vitro fertilization families (infant M = 11 months). Standardized interview and observational measures were used to assess mother–infant and father–infant relationship quality at the representational and behavioral levels. Few differences were found between family types in parents’ representations of the parent–infant relationship. Differences were found between family types in the observational assessment of mother–infant relationship quality, indicating less optimal interactions in egg donation families. Findings suggest that egg donation families function well in infancy overall, but there may be subtle yet meaningful differences in mother–infant interaction quality. 相似文献
26.
We describe an activity that introduces students to population modelling, enables them to use estimates obtained from a sample to infer back to the population, and understands how the findings are translatable via penguins and their poo! 相似文献
27.
In this study, we examined the anthropometric dimensions of powerlifters across various body mass (competitive bodyweight) categories. Fifty-four male Oceania competitive powerlifters (9 lightweight, 30 middleweight, and 15 heavyweight) were recruited from one international and two national powerlifting competitions held in New Zealand. Powerlifters were assessed for 37 anthropometric dimensions by ISAK (International Society for the Advancement of Kinanthropometry) level II and III accredited anthropometrists. The powerlifters were highly mesomorphic and had large girths and bony breadths, both in absolute units and when expressed as Z(p)-scores compared through the Phantom (Ross & Wilson, 1974). These anthropometric characteristics were more pronounced in heavyweights, who were significantly heavier, had greater muscle and fat mass, were more endo-mesomorphic, and had larger girths and bony breadths than the lighter lifters. Although middleweight and heavyweight lifters typically had longer segment lengths than the lightweights, all three groups had similar Zp-scores for the segment lengths, indicating similar segment length proportions. While population comparisons would be required to identify any connection between specific anthropometric dimensions that confer a competitive advantage to the expression of maximal strength, anthropometric profiling may prove useful for talent identification and for the assessment of training progression in powerlifting. 相似文献
28.
Intake interviews were analyzed from 365 adults molested as children (AMACs). The AMACs were entering treatment at the Child Sexual Abuse Treatment Program (San Jose, CA). This study presents data on the relationship of the perpetrator to the victim, and whether most molestations include intercourse. The majority of the perpetrators (62%) were either biological fathers or father-surrogates. Ninety-nine percent of the perpetrators were known to the victim; 97% were male. As in past studies, fondling from the waist down was the most common type of molestation, occurring in 92% of the cases. Forty-four percent of cases included intercourse. The present findings are compared with past research and are discussed in the context of common misconceptions associated with child sexual abuse. 相似文献
29.
30.
Interdisciplinary research is frequently viewed as an important component of the research landscape through its innovative ability to integrate knowledge from different areas. However, support for interdisciplinary research is often strategic rhetoric, with policy-makers and universities frequently adopting practices that favour disciplinary performance. We argue that disciplinary and interdisciplinary research are complementary, and we develop a simple framework that demonstrates this for a semi-permanent interdisciplinary research field. We argue that the presence of communicating infrastructures fosters communication and integration between disciplines and the interdisciplinary research field to generate innovative knowledge. We apply this to the experience of economic history in Australia in the second half of the twentieth century to demonstrate the life cycle of a semi-permanent interdisciplinary research field. 相似文献