全文获取类型
收费全文 | 2242篇 |
免费 | 182篇 |
国内免费 | 1篇 |
出版年
2022年 | 9篇 |
2021年 | 40篇 |
2020年 | 20篇 |
2019年 | 34篇 |
2018年 | 49篇 |
2017年 | 30篇 |
2016年 | 68篇 |
2015年 | 113篇 |
2014年 | 98篇 |
2013年 | 129篇 |
2012年 | 223篇 |
2011年 | 161篇 |
2010年 | 119篇 |
2009年 | 119篇 |
2008年 | 149篇 |
2007年 | 140篇 |
2006年 | 121篇 |
2005年 | 106篇 |
2004年 | 109篇 |
2003年 | 110篇 |
2002年 | 97篇 |
2001年 | 20篇 |
2000年 | 15篇 |
1999年 | 24篇 |
1998年 | 25篇 |
1997年 | 19篇 |
1996年 | 12篇 |
1995年 | 16篇 |
1994年 | 18篇 |
1993年 | 14篇 |
1992年 | 17篇 |
1991年 | 16篇 |
1990年 | 18篇 |
1989年 | 9篇 |
1988年 | 10篇 |
1987年 | 17篇 |
1985年 | 10篇 |
1984年 | 7篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1981年 | 9篇 |
1979年 | 6篇 |
1976年 | 6篇 |
1975年 | 6篇 |
1973年 | 7篇 |
1972年 | 6篇 |
1971年 | 6篇 |
1968年 | 6篇 |
1967年 | 6篇 |
1966年 | 7篇 |
排序方式: 共有2425条查询结果,搜索用时 15 毫秒
181.
Colin J. Yates David J. Coates Carole Elliott Margaret Byrne 《Biodiversity and Conservation》2007,16(5):1379-1395
In this study we investigate the composition of the potential honeyeater pollinator community, patterns of honeyeater visitation,
pollination and the mating system in a range of population fragments for the bird-pollinated mixed mating system shrub Calothamnus quadrifidus R.Br. Specifically, we aimed to answer the following questions. For smaller and more isolated population fragments are honeyeater
species lost from the pollinator community, patterns of visitation different, levels of pollination lower and rates of selfing,
biparental inbreeding and correlated paternity higher. The composition of the honeyeater community was similar across population
fragments and there was no relationship between the abundance of birds and population fragment size. Honeyeaters were most
commonly observed visiting numerous inflorescences within single plants in all populations, but as population fragments became
larger movements between plants were more commonly observed. Our observations of honeyeater visitation were generally consistent
with our measurements of pollination and patterns in the mating system across population fragments. We found no significant
relationship between population fragment size and levels of pollination. Mating system studies showed outcrossing rates (t
m) comparable to those found in other bird-pollinated Myrtaceae, and ranged from 0.54 to 0.90 across populations. Outcrossing
rates were not significantly correlated with log population size, but correlations of outcrossed paternity indicate a clear
trend from low correlated paternity in larger populations to significantly higher correlated paternities in smaller populations.
As a consequence mating in small populations will occur between much smaller groups of plants, and this may affect population
fitness in subsequent generations. 相似文献
182.
183.
184.
185.
This article offers a briefing in one of the knowledge management issues of in silico experimentation in bioinformatics. Recording of the provenance of an experiment-what was done; where, how and why, etc. is an important aspect of scientific best practice that should be extended to in silico experimentation. We will do this in the context of eScience which has been part of the move of bioinformatics towards an industrial setting. Despite the computational nature of bioinformatics, these analyses are scientific and thus necessitate their own versions of typical scientific rigour. Just as recording who, what, why, when, where and how of an experiment is central to the scientific process in laboratory science, so it should be in silico science. The generation and recording of these aspects, or provenance, of an experiment are necessary knowledge management goals if we are to introduce scientific rigour into routine bioinformatics. In Silico experimental protocols should themselves be a form of managing the knowledge of how to perform bioinformatics analyses. Several systems now exist that offer support for the generation and collection of provenance information about how a particular in silico experiment was run, what results were generated, how they were generated, etc. In reviewing provenance support, we will review one of the important knowledge management issues in bioinformatics. 相似文献
186.
Ricardo Saban Michael R D'Andrea Patricia Andrade-Gordon Claudia K Derian Igor Dozmorov Michael A Ihnat Robert E Hurst Carole A Davis Cindy Simpson Marcia R Saban 《BMC physiology》2007,7(1):4
Background
In general, inflammation plays a role in most bladder pathologies and represents a defense reaction to injury that often times is two edged. In particular, bladder neurogenic inflammation involves the participation of mast cells and sensory nerves. Increased mast cell numbers and tryptase release represent one of the prevalent etiologic theories for interstitial cystitis and other urinary bladder inflammatory conditions. The activity of mast cell-derived tryptase as well as thrombin is significantly increased during inflammation. Those enzymes activate specific G-protein coupled proteinase-activated receptors (PAR)s. 相似文献187.
188.
189.
190.
Characterization of Helicobacter pylori HP0231 (DsbK): role in disulfide bond formation,redox homeostasis and production of Helicobacter cystein‐rich protein HcpE
下载免费PDF全文
![点击此处可从《Molecular microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Brandon Oickle Spencer Fairweather Alexander Oberc Jaspreet Chahal Dinath Ratnayake Carole Creuzenet 《Molecular microbiology》2015,96(1):110-133
Helicobacter pylori is a human gastric pathogen that colonizes ~ 50% of the world's population. It can cause gastritis, gastric or duodenal ulcers and also gastric cancer. The numerous side effects of available treatments and the emergence of antibiotic resistant strains are severe concerns that justify further research into H. pylori's pathogenic mechanisms. H. pylori produces secreted proteins that may play a role in virulence, including the Helicobacter cysteine‐rich protein HcpE (aka HP0235). We demonstrate herein that HcpE is secreted in the culture supernatant both as a soluble protein and in association with outer membrane vesicles. We show that the structure of HcpE comprises an organized array of disulfide bonds. We identify DsbK (aka HP0231) as a folding factor necessary for HcpE production and secretion in H. pylori and show that recombinant DsbK can interact with and refold unprocessed, reduced HcpE in vitro. These experiments highlight the first biologically relevant substrate for DsbK. Furthermore, we show that DsbK has disulfide bond (Dsb) forming activity on reduced lysozyme and demonstrate a DsbA‐type of activity for DsbK upon expression in E. coli, despite its similarity with DsbG. Finally, we show a role of DsbK in maintaining redox homeostasis in H. pylori. 相似文献