全文获取类型
收费全文 | 766篇 |
免费 | 52篇 |
出版年
2021年 | 12篇 |
2020年 | 11篇 |
2019年 | 15篇 |
2018年 | 8篇 |
2017年 | 16篇 |
2016年 | 12篇 |
2015年 | 37篇 |
2014年 | 26篇 |
2013年 | 39篇 |
2012年 | 55篇 |
2011年 | 49篇 |
2010年 | 40篇 |
2009年 | 31篇 |
2008年 | 46篇 |
2007年 | 38篇 |
2006年 | 35篇 |
2005年 | 34篇 |
2004年 | 38篇 |
2003年 | 32篇 |
2002年 | 23篇 |
2001年 | 8篇 |
2000年 | 6篇 |
1999年 | 6篇 |
1998年 | 9篇 |
1996年 | 8篇 |
1994年 | 13篇 |
1993年 | 8篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 7篇 |
1988年 | 4篇 |
1987年 | 7篇 |
1986年 | 4篇 |
1985年 | 8篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1980年 | 5篇 |
1979年 | 7篇 |
1978年 | 4篇 |
1975年 | 5篇 |
1974年 | 4篇 |
1970年 | 4篇 |
1958年 | 5篇 |
1957年 | 5篇 |
1955年 | 11篇 |
1954年 | 4篇 |
1953年 | 3篇 |
1952年 | 7篇 |
1950年 | 5篇 |
1949年 | 3篇 |
排序方式: 共有818条查询结果,搜索用时 31 毫秒
21.
Yavno Stan Gobin Jenilee Wilson Chris C. Vila-Gispert Anna Copp Gordon H. Fox Michael G. 《Hydrobiologia》2020,847(2):345-364
Hydrobiologia - To determine the origin of introduced European populations of pumpkinseed Lepomis gibbosus (Linnaeus, 1758)—a freshwater sunfish, native to eastern North America that has... 相似文献
22.
23.
Marzia Scortegagna Chelsea Ruller Surya K. De Elisa Barile Stan Krajewski Pedro Aza‐Blanc Roy Williams Anthony B. Pinkerton Michael Jackson Lynda Chin Maurizio Pellecchia Marcus Bosenberg Ze'ev A. Ronai 《Pigment cell & melanoma research》2013,26(1):136-142
To date, there are no effective therapies for tumors bearing NRAS mutations, which are present in 15–20% of human melanomas. Here we extend our earlier studies where we demonstrated that the small molecule BI‐69A11 inhibits the growth of melanoma cell lines. Gene expression analysis revealed the induction of interferon‐ and cell death‐related genes that were associated with responsiveness of melanoma cell lines to BI‐69A11. Strikingly, the administration of BI‐69A11 inhibited melanoma development in genetically modified mice bearing an inducible form of activated Nras and a deletion of the Ink4a gene (Nras(Q61K)::Ink4a?/?). Biweekly administration of BI‐69A11 starting at 10 weeks or as late as 24 weeks after the induction of mutant Nras expression inhibited melanoma development (100 and 36%, respectively). BI‐69A11 treatment did not inhibit the development of histiocytic sarcomas, which constitute about 50% of the tumors in this model. BI‐69A11‐resistant Nras(Q61K)::Ink4a?/? tumors exhibited increased CD45 expression, reflective of immune cell infiltration and upregulation of gene networks associated with the cytoskeleton, DNA damage response, and small molecule transport. The ability to attenuate the development of NRAS mutant melanomas supports further development of BI‐69A11 for clinical assessment. 相似文献
24.
Niels J. H. M. Gerrits Anita C. van Loenhoud Stan F. van den Berg Henk W. Berendse Elisabeth M. J. Foncke Martin Klein Diederick Stoffers Ysbrand D. van der Werf Odile A. van den Heuvel 《PloS one》2016,11(2)
Parkinson’s disease (PD) is often associated with cognitive deficits, although their severity varies considerably between patients. Recently, we used voxel-based morphometry (VBM) to show that individual differences in gray matter (GM) volume relate to cognitive heterogeneity in PD. VBM does, however, not differentiate between cortical thickness (CTh) and surface area (SA), which might be independently affected in PD. We therefore re-analyzed our cohort using the surface-based method FreeSurfer, and investigated (i) CTh, SA, and (sub)cortical GM volume differences between 93 PD patients and 45 matched controls, and (ii) the relation between these structural measures and cognitive performance on six neuropsychological tasks within the PD group. We found cortical thinning in PD patients in the left pericalcarine gyrus, extending to cuneus, precuneus and lingual areas and left inferior parietal cortex, bilateral rostral middle frontal cortex, and right cuneus, and increased cortical surface area in the left pars triangularis. Within the PD group, we found negative correlations between (i) CTh of occipital areas and performance on a verbal memory task, (ii) SA and volume of the frontal cortex and visuospatial memory performance, and, (iii) volume of the right thalamus and scores on two verbal fluency tasks. Our primary findings illustrate that i) CTh and SA are differentially affected in PD, and ii) VBM and FreeSurfer yield non-overlapping results in an identical dataset. We argue that this discrepancy is due to technical differences and the subtlety of the PD-related structural changes. 相似文献
25.
26.
Christopher B. Cooper Edward J. Beard lvaro Vzquez‐Mayagoitia Liliana Stan Gavin B. G. Stenning Daniel W. Nye Julian A. Vigil Tina Tomar Jingwen Jia Govardhana B. Bodedla Song Chen Lucía Gallego Santiago Franco Antonio Carella K. R. Justin Thomas Song Xue Xunjin Zhu Jacqueline M. Cole 《Liver Transplantation》2019,9(5)
Data‐driven materials discovery has become increasingly important in identifying materials that exhibit specific, desirable properties from a vast chemical search space. Synergic prediction and experimental validation are needed to accelerate scientific advances related to critical societal applications. A design‐to‐device study that uses high‐throughput screens with algorithmic encodings of structure–property relationships is reported to identify new materials with panchromatic optical absorption, whose photovoltaic device applications are then experimentally verified. The data‐mining methods source 9431 dye candidates, which are auto‐generated from the literature using a custom text‐mining tool. These candidates are sifted via a data‐mining workflow that is tailored to identify optimal combinations of organic dyes that have complementary optical absorption properties such that they can harvest all available sunlight when acting as co‐sensitizers for dye‐sensitized solar cells (DSSCs). Six promising dye combinations are shortlisted for device testing, whereupon one dye combination yields co‐sensitized DSSCs with power conversion efficiencies comparable to those of the high‐performance, organometallic dye, N719. These results demonstrate how data‐driven molecular engineering can accelerate materials discovery for panchromatic photovoltaic or other applications. 相似文献
27.
Christopher B. Cooper Edward J. Beard lvaro Vzquez‐Mayagoitia Liliana Stan Gavin B. G. Stenning Daniel W. Nye Julian A. Vigil Tina Tomar Jingwen Jia Govardhana B. Bodedla Song Chen Lucía Gallego Santiago Franco Antonio Carella K. R. Justin Thomas Song Xue Xunjin Zhu Jacqueline M. Cole 《Liver Transplantation》2019,9(5)
28.
29.
Ctia Bandeiras Joaquim M. S. Cabral Robert A. Gabbay Stan N. Finkelstein Frederico Castelo Ferreira 《Biotechnology journal》2019,14(8)
Differentiation of pluripotent stem cells (PSCs) into β cells could provide insulin independence for type 1 diabetes (T1D) patients. This approach would reduce the clinical complications that most patients managed on intensive insulin therapy (IIT) face. However, bottlenecks of PSC manufacturing and limited engraftment of encapsulated cells hinder the long‐term effectiveness of these therapies. A bioprocess decision‐support tool is combined with a disease state‐transition model to evaluate the cost‐effectiveness of the stem cell‐based therapy against IIT. Clinical effectiveness is assessed in quality‐adjusted life years (QALYs). Manufacturing costs per patient reduce from $430 000 to $160 000 with optimization of batch size and annual demand. For 96% of the patients, cell therapy improves the quality of life compared to IIT. Cost savings are achieved for 2% of the population through prevention of renal disease. The therapy is cost‐effective for 3.4% of patients when a willingness to pay (WTP) of up to $150 000 per QALY is considered. A 75% cost reduction in the cell therapy price increases cost‐effectiveness likelihood to 51% at $100 000 per QALY. This study highlights the need for scalable manufacturing platforms for stem cell therapies, as well as to prioritizing access to the therapy to patients with an increased likelihood of costly complications. 相似文献
30.
Murata T Lin MI Stan RV Bauer PM Yu J Sessa WC 《The Journal of biological chemistry》2007,282(22):16631-16643
Various cellular signals initiate calcium entry into cells, and there is evidence that lipid rafts and caveolae may concentrate proteins that regulate transmembrane calcium fluxes. Here, using mice deficient in caveolin-1 (Cav-1) and Cav-1 knock-out reconstituted with endothelium-specific Cav-1, we show that Cav-1 is essential for calcium entry in endothelial cells and governs the localization and protein-protein interactions between transient receptor channels C4 and C1. Thus, Cav-1 is required for calcium entry in vascular endothelial cells and perhaps other specialized cell types containing caveolae. 相似文献