全文获取类型
收费全文 | 414篇 |
免费 | 36篇 |
国内免费 | 1篇 |
专业分类
451篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 9篇 |
2020年 | 18篇 |
2019年 | 41篇 |
2018年 | 29篇 |
2017年 | 5篇 |
2016年 | 9篇 |
2015年 | 8篇 |
2014年 | 8篇 |
2013年 | 24篇 |
2012年 | 6篇 |
2010年 | 10篇 |
2009年 | 8篇 |
2008年 | 13篇 |
2007年 | 19篇 |
2006年 | 21篇 |
2005年 | 16篇 |
2004年 | 5篇 |
2003年 | 7篇 |
2002年 | 12篇 |
2001年 | 15篇 |
2000年 | 6篇 |
1999年 | 13篇 |
1998年 | 16篇 |
1997年 | 7篇 |
1996年 | 19篇 |
1995年 | 15篇 |
1994年 | 4篇 |
1993年 | 11篇 |
1992年 | 10篇 |
1991年 | 4篇 |
1990年 | 5篇 |
1989年 | 12篇 |
1988年 | 2篇 |
1987年 | 5篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1984年 | 6篇 |
1983年 | 2篇 |
1981年 | 2篇 |
1980年 | 4篇 |
1979年 | 1篇 |
1978年 | 4篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1973年 | 3篇 |
1938年 | 1篇 |
1931年 | 1篇 |
1926年 | 1篇 |
排序方式: 共有451条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
Fluorescent chemosensors of protein kinase activity provide a continuous, high-throughput sensing format for the study of the roles of these enzymes, which are crucial for regulating cellular function. Specifically, chemosensors using the nonnatural amino acid, Sox, and physiological Mg(2+) levels report phosphorylation with dramatic fluorescence changes that are amenable to real-time and high-throughput analysis. In this article, we report 15 probes for a total of six distinct serine/threonine kinases with large fluorescence increases and good reactivity toward the target kinase. The sensing mechanism is detailed, and the optimal sensing motif is determined. These versatile and powerful sensors provide tools for researchers studying the roles of the targeted kinases in signal transduction, and the design principles provide guidelines for the generation of future fluorescent chemosensors for any serine/threonine kinase. 相似文献
95.
Peizhong Zheng MD Ali Babar Seshasai Parthasarathy Ryan Gibson Kelly Parliament Josh Flook Thomas Patterson Peter Friedemann Siva Kumpatla Steve Thompson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(7):1537-1547
Key message
We identified a G-nucleotide insertion in a maize FatB responsible for reducing saturated fatty acids through QTL mapping and map-based cloning and developed an allele-specific DNA marker for molecular breeding.Abstract
Vegetable oils with reduced saturated fatty acids have signficant health benefits. SRS72NE, a Dow AgroSciences proprietory maize inbred line, was found to contain signficantly reduced levels of palmitic acid and total saturated fatty acids in seed oil when compared to other common inbreds. Using F2 and F3 populations derived from a cross between SRS72NE and a normal inbred SLN74, we have demonstrated that the reduced saturated fatty acid phenotype in SRS72NE is controlled by a single QTL on chromosome 9 that explains 79.1 % of palmitic acid and 79.6 % total saturated fatty acid variations. The QTL was mapped to an interval of 105 kb that contains one single gene, a type B fatty acyl-ACP thioesterase (ZmFatB; GRMZM5G829544). ZmFatB alleles from SRS72NE and common inbreds were cloned and sequenced. SRS72NE fatb allele contains a single nucleotide (G) insertion in the 6th exon, which creates a premature stop codon 22 base pairs down stream. As a result, ZmFatB protein from SRS72NE is predicted to contain eight altered and 90 deleted amino acids at its C-terminus. Because the affected region is part of the conserved acyl-ACP thioesterase catalytic domain, the truncated ZmFatB in SRS72NE is likely non-functional. We also show that fatb RNA level in SRS72NE is reduced by 4.4-fold when compared to the normal allele SNL74. A high throughput DNA assay capable of differentiating the normal and reduced saturate fatty acid alleles has been developed and can be used for accelerated molecular breeding. 相似文献96.
97.
98.
The Stomach, Helicobacter pylori, and Acid Secretion 总被引:1,自引:0,他引:1
99.
Qichen Yang MSc Vishal Jhanji MD Sze Qin Tan BSc Kwok Ping Chan BSc Di Cao PhD Wai Kit Chu DPhil Mingzhi Zhang MD Chi Pui Pang DPhil Tsz Kin Ng PhD 《Journal of cellular biochemistry》2019,120(3):4203-4213
Pterygium is a triangular-shaped hyperplastic growth, characterized by conjunctivalization, inflammation, and connective tissue remodeling. Our previous meta-analysis found that cigarette smoking is associated with a reduced risk of pterygium. Yet, the biological effect of cigarette smoke components on pterygium has not been studied. Here we reported the proliferation and migration properties of human primary pterygium cells with continuous exposure to nicotine and cotinine. Human primary pterygium cells predominantly expressed the α5, β1, and γ subunits of the nicotinic acetylcholine receptor. Continuous exposure to the mixture of 0.15 μM nicotine and 2 μM cotinine retarded pterygium cell proliferation by 16.04% (P = 0.009) and hindered their migration by 11.93% ( P = 0.039), without affecting cell apoptosis. SNAIL and α-smooth muscle actin protein expression was significantly downregulated in pterygium cells treated with 0.15 μM nicotine-2 μM cotinine mixture by 1.33- ( P = 0.036) and 1.31-fold ( P = 0.001), respectively. Besides, the 0.15 μM nicotine-2 μM cotinine mixture also reduced matrix metalloproteinase (MMP)-1 and MMP-9 expressions in pterygium cells by 1.56- ( P = 0.043) and 1.27-fold ( P = 0.012), respectively. In summary, this study revealed that continuous exposure of nicotine and cotinine inhibited human primary pterygium cell proliferation and migration in vitro by reducing epithelial-to-mesenchymal transition and MMP protein expression, partially explaining the lower incidence of pterygium in cigarette smokers. 相似文献
100.