全文获取类型
收费全文 | 860篇 |
免费 | 45篇 |
国内免费 | 1篇 |
出版年
2023年 | 4篇 |
2022年 | 6篇 |
2021年 | 22篇 |
2020年 | 22篇 |
2019年 | 17篇 |
2018年 | 20篇 |
2017年 | 32篇 |
2016年 | 43篇 |
2015年 | 54篇 |
2014年 | 54篇 |
2013年 | 63篇 |
2012年 | 68篇 |
2011年 | 83篇 |
2010年 | 51篇 |
2009年 | 38篇 |
2008年 | 55篇 |
2007年 | 58篇 |
2006年 | 38篇 |
2005年 | 44篇 |
2004年 | 33篇 |
2003年 | 21篇 |
2002年 | 25篇 |
2001年 | 5篇 |
2000年 | 4篇 |
1999年 | 1篇 |
1998年 | 5篇 |
1997年 | 1篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 5篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1975年 | 2篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1971年 | 3篇 |
1970年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有906条查询结果,搜索用时 846 毫秒
51.
52.
53.
54.
55.
Monica Y. Burgos Zepeda Kevin Alessandri Dorothée Murat Chahrazade El Amri Elie Dassa 《Biochimica et Biophysica Acta - Proteins and Proteomics》2010,1804(4):755-761
The Uup protein belongs to a subfamily of soluble ATP-binding cassette (ABC) ATPases that have been implicated in several processes different from transmembrane transport of molecules, such as transposon precise excision. We have demonstrated previously that Escherichia coli Uup is able to bind DNA. DNA binding capacity is lowered in a truncated Uup protein lacking its C-terminal domain (CTD), suggesting a contribution of CTD to DNA binding. In the present study, we characterize the role of CTD in the function of Uup, on its overall stability and in DNA binding. To this end, we expressed and purified isolated CTD and we investigated the structural and functional role of this domain. The results underline that CTD is essential for the function of Uup, is stable and able to fold up autonomously. We compared the DNA binding activities of three versions of the protein (Uup, UupΔCTD and CTD) by an electrophoretic mobility shift assay. CTD is able to bind DNA although less efficiently than intact Uup and UupΔCTD. These observations suggest that CTD is an essential domain that contributes directly to the DNA binding ability of Uup. 相似文献
56.
In this study, mainly biological treatment of prawn waste for chitin production was investigated. Lactic acid and protease
fermentations were applied to extract chitin from prawn waste in the presence of various glucose concentrations. The results
obtained were also compared with those of chemical method which was consisted of first mineral removal and then protein removal
sequence. Different strategies were applied using lactic acid producing bacterium, Lactococcus lactis, and a protease producer, marine bacterium Teredinobacter turnirae. Both bacteria were first cultivated individually and then cofermented. In their individual cultivation, L. lactis removed the inorganic materials efficiently, while T. turnirae performed better in deproteinization process. Cofermentation of both bacteria was also conducted using three different protocols.
The highest process yield (95.5%) was obtained when T. turnirae was first inoculated. Although the extraction of chitin by biological treatment was incomplete compared to the chemical method,
the biological treatment employed here could still be considered as an alternative method in a more environmentally benign
approach. 相似文献
57.
Imed Sbissi Mohamed Neffati Abdellatif Boudabous Claude Murat Maher Gtari 《Antonie van Leeuwenhoek》2010,98(4):429-436
The molecular phylogeny and comparative morphological studies reported here provide evidence for the recognition of the genus
Picoa, an hypogeous desert truffle, in the family Pyronemataceae (Ascomycota, Pezizales). Picoa juniperi and Picoa lefebvrei were reassigned to the genus Picoa based on large subunit (LSU) sequence (28S) rDNA and internal transcribed spacer (ITS) rDNA (including the partial 18S, ITS1,
ITS2, 5.8S gene, and partial 28S of the nuclear rDNA) data. Morphological studies of spores, asci, perida, and gleba revealed
high similarities between P. lefebvrei and P. juniperi, thereby confirming the membership of both species in the genus Picoa. These two species were primarily distinguishable based on ascospore ornamentation. 相似文献
58.
Fahriye Ceyda Dudak Esra Acar Soykut Murat Erman Oğuz Fatih Yaşar İsmail Hakkı Boyacı 《Journal of molecular recognition : JMR》2010,23(4):369-378
Staphylococcal enterotoxin B (SEB) is an exotoxin produced by Staphylococcus aureus and commonly associated with food poisoning. In this study, SEB‐binding peptides were identified by screening a phage displayed peptide library. The binding of peptides to SEB was tested with isothermal titration calorimetry (ITC) and of the five selected peptides, three showed affinity to SEB, with one measured to have the highest affinity constant (105 M?1). ITC revealed that the interaction of peptide ligands with SEB was driven entropically and the binding was dominated by hydrophobic interactions. Circular dichroism (CD) measurements and molecular dynamics (MD) simulations, together, give a structural insight into the interaction of peptides with SEB. While SEB binding peptides showed random coil structure before binding, after complex formation they had more ordered structures. The peptide with highest affinity to SEB showed stable conformation during MD simulation. Taken together, our approach about thermodynamic and structural characterization of peptide ligands can be used to develop aptamers, with high affinity and selectivity, for biosensor applications. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
59.
Murat Ayaz Nizamettin Dalkilic Hulagu Bariskaner Seckin Tuncer Ilhami Demirel 《Biological trace element research》2007,116(3):301-309
Gender differences are related to the manner in which the heart responds to chronic and acute stress conditions of physiological
and pathological nature. Depending on dose, sodium selenite acts as an antioxidant proven to have beneficial effects in several
pathological conditions G. Drasch, J. Schopfer, and G. N. Schrauzer, Selenium/cadmium ratios in human prostates: indicators
of prostate cancer risk of smokers and non-smokers, and relevance to the cancer protective effects of selenium,Biol. Trace Element Res.
103(2), 103–107 (2005); R. G. Kasseroller and G. N. Schrauzer, Treatment of secondary lymphedema of the arm with physical decongestive
therapy and sodium selenite: a review,Am. J. Ther.
7(4), 273–279 (2000); G. N. Schrauzer, Anticarcinogenic effects of selenium,Cell. Mol. Life Sci.
57(13–14), 1864–1873 (2000); I. S. Palmer and O. E. Olson, Relative toxicities of selenite and selenate in the drinking water of rats,J. Nutr.
104(3), 306–314 (1974). To date, little is known about the gender-dependent direct effects of toxic doses of selenite on electrophysiology
of the cardiovascular system H. A. Schroeder and M. Mitchener, Selenium and tellurium in rats: effect on growth, survival
and tumors,J. Nutr.
101(11), 1531–1540 (1971); G. N. Schrauzer, The nutritional significance, metabolism and toxicology of selenomethionine,Adv. Food Nutr. Res.
47, 73–112 (2003). In the present study, the effects of in vitro toxic concentrations of sodium selenite ranging from 10-6 M to 10-3 M were tested on both male and female rat heart preparations. The toxic effects seen in an electrocardiogram and left ventricular
pressure were dose and sex dependent at most of the tested concentrations. The present study clearly shows that at toxic doses,
stress conditions are induced by selenite, resulting in gender-dependent modifications of the heart function. This modification
is more pronounced in the contraction cascade of female rats. Males, on the other hand, had been much more affected in excitation-related
parameters. 相似文献
60.