全文获取类型
收费全文 | 14323篇 |
免费 | 797篇 |
国内免费 | 12篇 |
专业分类
15132篇 |
出版年
2024年 | 53篇 |
2023年 | 87篇 |
2022年 | 204篇 |
2021年 | 380篇 |
2020年 | 208篇 |
2019年 | 251篇 |
2018年 | 315篇 |
2017年 | 242篇 |
2016年 | 419篇 |
2015年 | 617篇 |
2014年 | 696篇 |
2013年 | 827篇 |
2012年 | 1153篇 |
2011年 | 1143篇 |
2010年 | 713篇 |
2009年 | 655篇 |
2008年 | 908篇 |
2007年 | 889篇 |
2006年 | 879篇 |
2005年 | 769篇 |
2004年 | 735篇 |
2003年 | 703篇 |
2002年 | 622篇 |
2001年 | 166篇 |
2000年 | 106篇 |
1999年 | 170篇 |
1998年 | 166篇 |
1997年 | 115篇 |
1996年 | 114篇 |
1995年 | 73篇 |
1994年 | 80篇 |
1993年 | 81篇 |
1992年 | 47篇 |
1991年 | 54篇 |
1990年 | 40篇 |
1989年 | 48篇 |
1988年 | 32篇 |
1987年 | 30篇 |
1986年 | 22篇 |
1985年 | 50篇 |
1984年 | 44篇 |
1983年 | 32篇 |
1982年 | 23篇 |
1981年 | 31篇 |
1980年 | 27篇 |
1979年 | 14篇 |
1978年 | 11篇 |
1977年 | 13篇 |
1976年 | 11篇 |
1975年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Ryan A. Flynn Julia A. Belk Yanyan Qi Yuki Yasumoto Jin Wei Mia Madel Alfajaro Quanming Shi Maxwell R. Mumbach Aditi Limaye Peter C. DeWeirdt Cameron O. Schmitz Kevin R. Parker Elizabeth Woo Howard Y. Chang Tamas L. Horvath Jan E. Carette Carolyn R. Bertozzi Craig B. Wilen Ansuman T. Satpathy 《Cell》2021,184(9):2394-2411.e16
- Download : Download high-res image (195KB)
- Download : Download full-size image
2.
Simone S. Riedel Congcong Lu Hongbo M. Xie Kevin Nestler Marit W. Vermunt Alexandra Lenard Laura Bennett Nancy A. Speck Ichiro Hanamura Julie A. Lessard Gerd A. Blobel Benjamin A. Garcia Kathrin M. Bernt 《Molecular cell》2021,81(11):2332-2348.e9
- Download : Download high-res image (137KB)
- Download : Download full-size image
3.
Historical Ecology on Sandoy, Faroe Islands: Palaeoenvironmental and Archaeological Perspectives 总被引:1,自引:1,他引:0
Ian T. Lawson Mike J. Church Tom H. McGovern Símun V. Arge James Woollet Kevin J. Edwards Freddy J. Gathorne-Hardy Andrew J. Dugmore Gordon Cook Kerry-Anne Mairs Amanda M. Thomson Guðrún Sveinbjarnardótti 《Human ecology: an interdisciplinary journal》2005,33(5):651-684
We present palaeoenvironmental, geomorphological, archaeological, and place-name data which allow a holistic assessment of
the history of landscape change on Sandoy, Faroe Islands, especially in terms of the changes that occurred in response to
the colonization of the island by humans. In contrast to other situations in the North Atlantic region, there is considerable
continuity in the patterns and processes of landscape evolution across the initial settlement horizon. Many of the characteristic
features of post-settlement North Atlantic landscapes—absence of trees, widespread blanket mires, high rates of soil erosion—were
already in place when the first people arrived. Although human impact on Sandoy appears to have been light, conversely, the
unusual environment forced major alterations of the subsistence economy imported by the colonists. Settlement-era archaeological
records suggest that, from the start, patterns of resource use differed substantially from the regional norm, and these differences
became amplified over time as the Faroese economy created a locally sustainable cultural landscape. 相似文献
4.
Niche construction is the process whereby organisms modify selective environments, thereby affecting evolution. The niche‐construction perspective is particularly relevant to researchers using evolutionary methods to interpret human behavior and society. On the basis of niche‐construction theory, we argue against the hypothesis that modern humans experience an atypically large adaptive lag. We stress that humans construct their world largely to suit themselves and frequently buffer adaptive lag through cultural niche construction. Where they are unable to do that, natural selection of genes rapidly ensues. Our argument has implications for evolutionary psychology and human behavioral ecology, and suggests that the methods of the latter are potentially applicable to all human societies, even postindustrial ones. 相似文献
5.
6.
7.
Suman Kundu Talat Roome Ashish Bhattacharjee Kevin A. Carnevale Valentin P. Yakubenko Renliang Zhang Sung Hee Hwang Bruce D. Hammock Martha K. Cathcart 《Journal of lipid research》2013,54(2):436-447
Monocyte chemoattractant protein-1 (MCP-1)-induced monocyte chemotaxis is a major event in inflammatory disease. Our prior studies have demonstrated that MCP-1-dependent chemotaxis requires release of arachidonic acid (AA) by activated cytosolic phospholipase A2 (cPLA2). Here we investigated the involvement of AA metabolites in chemotaxis. Neither cyclooxygenase nor lipoxygenase pathways were required, whereas pharmacologic inhibitors of both the cytochrome-P450 (CYP) and the soluble epoxide hydrolase (sEH) pathways blocked monocyte chemotaxis to MCP-1. To verify specificity, we demonstrated that the CYP and sEH products epoxyeiscosatrienoic acids (EETs) and dihydroxyeicosatrienoic acids (DHETs), respectively, restored chemotaxis in the presence of the inhibitors, indicating that sEH-derived products are essential for MCP-1-driven chemotaxis. Importantly, DHETs also rescued chemotaxis in cPLA2-deficient monocytes and monocytes with blocked Erk1/2 activity, because Erk controls cPLA2 activation. The in vitro findings regarding the involvement of CYP/sEH pathways were further validated in vivo using two complementary approaches measuring MCP-1-dependent chemotaxis in mice. These observations reveal the importance of sEH in MCP-1-regulated monocyte chemotaxis and may explain the observed therapeutic value of sEH inhibitors in treatment of inflammatory diseases, cardiovascular diseases, pain, and even carcinogenesis. Their effectiveness, often attributed to increasing EET levels, is probably influenced by the impairment of DHET formation and inhibition of chemotaxis. 相似文献
8.
9.
Benjamin D. Stevens John Litchfield Jeffrey A. Pfefferkorn Karen Atkinson Christian Perreault Paul Amor Kevin Bahnck Martin A. Berliner Jessica Calloway Anthony Carlo David R. Derksen Kevin J. Filipski Mike Gumkowski Charanjeet Jassal Margit MacDougall Brendan Murphy Paul Nkansah John Pettersen Yan Zhang 《Bioorganic & medicinal chemistry letters》2013,23(24):6588-6592
Glucokinase (hexokinase IV) continues to be a compelling target for the treatment of type 2 diabetes given the wealth of supporting human genetics data and numerous reports of robust clinical glucose lowering in patients treated with small molecule allosteric activators. Recent work has demonstrated the ability of hepatoselective activators to deliver glucose lowering efficacy with minimal risk of hypoglycemia. While orally administered agents require a considerable degree of passive permeability to promote suitable exposures, there is no such restriction on intravenously delivered drugs. Therefore, minimization of membrane diffusion in the context of an intravenously agent should ensure optimal hepatic targeting and therapeutic index. This work details the identification a hepatoselective GKA exhibiting the aforementioned properties. 相似文献
10.