全文获取类型
收费全文 | 286篇 |
免费 | 1篇 |
国内免费 | 1篇 |
专业分类
系统科学 | 8篇 |
理论与方法论 | 2篇 |
现状及发展 | 63篇 |
研究方法 | 88篇 |
综合类 | 117篇 |
自然研究 | 10篇 |
出版年
2022年 | 2篇 |
2021年 | 1篇 |
2019年 | 1篇 |
2018年 | 4篇 |
2017年 | 6篇 |
2016年 | 11篇 |
2015年 | 1篇 |
2014年 | 8篇 |
2013年 | 5篇 |
2012年 | 27篇 |
2011年 | 40篇 |
2010年 | 15篇 |
2009年 | 3篇 |
2008年 | 22篇 |
2007年 | 24篇 |
2006年 | 21篇 |
2005年 | 20篇 |
2004年 | 19篇 |
2003年 | 19篇 |
2002年 | 20篇 |
2001年 | 1篇 |
1998年 | 2篇 |
1996年 | 1篇 |
1982年 | 1篇 |
1980年 | 3篇 |
1975年 | 2篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1968年 | 1篇 |
1967年 | 2篇 |
1965年 | 2篇 |
1964年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有288条查询结果,搜索用时 218 毫秒
101.
Ubiquitination-dependent cofactor exchange on LIM homeodomain transcription factors 总被引:14,自引:0,他引:14
Ostendorff HP Peirano RI Peters MA Schlüter A Bossenz M Scheffner M Bach I 《Nature》2002,416(6876):99-103
102.
Constância M Hemberger M Hughes J Dean W Ferguson-Smith A Fundele R Stewart F Kelsey G Fowden A Sibley C Reik W 《Nature》2002,417(6892):945-948
103.
104.
Kévin Baranger Yannick Marchalant Amandine E. Bonnet Nadine Crouzin Alex Carrete Jean-Michel Paumier Nathalie A. Py Anne Bernard Charlotte Bauer Eliane Charrat Katrin Moschke Mothoharu Seiki Michel Vignes Stefan F. Lichtenthaler Frédéric Checler Michel Khrestchatisky Santiago Rivera 《Cellular and molecular life sciences : CMLS》2016,73(1):217-236
105.
Anne Stephens 《Systemic Practice and Action Research》2012,25(1):1-14
Feminist Systems Theory (FST) is an emerging theory grounded in cultural ecofeminism and critical systems theory. FST’s contribution
is in a set of principles that contain implications for community development and social research. FST brings to the fore
the importance of valuing and considering the voices of people at the margins of social research and community development
projects and is an effort towards a new ontology and language of person and nature to adequately address environmental marginalization.
The ‘systems’ theory contribution to FST enriches our repertoires of methods and tools with an emphasis on systems thinking
characterised by the use of boundary analysis. FST is ideally situated to enhance systemic intervention practice, an application
of action research and participatory research practices. This paper will examine ‘process philosophy’ necessary to understand
the nature of boundary analysis and the implications for FST and praxis with relevant examples drawn from case studies of
current applications of FST in action research settings; (1) economic analysis and transition pathways; (2) policy analysis
of the Close the Gap strategy for Indigenous equality and equity in Australia; (3) a community food distribution system; and, (4) a community
health and diabetes prevention program. 相似文献
106.
107.
108.
Ferrón SR Charalambous M Radford E McEwen K Wildner H Hind E Morante-Redolat JM Laborda J Guillemot F Bauer SR Fariñas I Ferguson-Smith AC 《Nature》2011,475(7356):381-385
The gene for the atypical NOTCH ligand delta-like homologue 1 (Dlk1) encodes membrane-bound and secreted isoforms that function in several developmental processes in vitro and in vivo. Dlk1, a member of a cluster of imprinted genes, is expressed from the paternally inherited chromosome. Here we show that mice that are deficient in Dlk1 have defects in postnatal neurogenesis in the subventricular zone: a developmental continuum that results in depletion of mature neurons in the olfactory bulb. We show that DLK1 is secreted by niche astrocytes, whereas its membrane-bound isoform is present in neural stem cells (NSCs) and is required for the inductive effect of secreted DLK1 on self-renewal. Notably, we find that there is a requirement for Dlk1 to be expressed from both maternally and paternally inherited chromosomes. Selective absence of Dlk1 imprinting in both NSCs and niche astrocytes is associated with postnatal acquisition of DNA methylation at the germ-line-derived imprinting control region. The results emphasize molecular relationships between NSCs and the niche astrocyte cells of the microenvironment, identifying a signalling system encoded by a single gene that functions coordinately in both cell types. The modulation of genomic imprinting in a stem-cell environment adds a new level of epigenetic regulation to the establishment and maintenance of the niche, raising wider questions about the adaptability, function and evolution of imprinting in specific developmental contexts. 相似文献
109.
Gupta GP Nguyen DX Chiang AC Bos PD Kim JY Nadal C Gomis RR Manova-Todorova K Massagué J 《Nature》2007,446(7137):765-770
Metastasis entails numerous biological functions that collectively enable cancerous cells from a primary site to disseminate and overtake distant organs. Using genetic and pharmacological approaches, we show that the epidermal growth factor receptor ligand epiregulin, the cyclooxygenase COX2, and the matrix metalloproteinases 1 and 2, when expressed in human breast cancer cells, collectively facilitate the assembly of new tumour blood vessels, the release of tumour cells into the circulation, and the breaching of lung capillaries by circulating tumour cells to seed pulmonary metastasis. These findings reveal how aggressive primary tumorigenic functions can be mechanistically coupled to greater lung metastatic potential, and how such biological activities may be therapeutically targeted with specific drug combinations. 相似文献
110.
Hakim O Resch W Yamane A Klein I Kieffer-Kwon KR Jankovic M Oliveira T Bothmer A Voss TC Ansarah-Sobrinho C Mathe E Liang G Cobell J Nakahashi H Robbiani DF Nussenzweig A Hager GL Nussenzweig MC Casellas R 《Nature》2012,484(7392):69-74
Recurrent chromosomal translocations underlie both haematopoietic and solid tumours. Their origin has been ascribed to selection of random rearrangements, targeted DNA damage, or frequent nuclear interactions between translocation partners; however, the relative contribution of each of these elements has not been measured directly or on a large scale. Here we examine the role of nuclear architecture and frequency of DNA damage in the genesis of chromosomal translocations by measuring these parameters simultaneously in cultured mouse B lymphocytes. In the absence of recurrent DNA damage, translocations between Igh or Myc and all other genes are directly related to their contact frequency. Conversely, translocations associated with recurrent site-directed DNA damage are proportional to the rate of DNA break formation, as measured by replication protein A accumulation at the site of damage. Thus, non-targeted rearrangements reflect nuclear organization whereas DNA break formation governs the location and frequency of recurrent translocations, including those driving B-cell malignancies. 相似文献