全文获取类型
收费全文 | 2778篇 |
免费 | 405篇 |
出版年
2022年 | 14篇 |
2021年 | 52篇 |
2020年 | 18篇 |
2019年 | 29篇 |
2018年 | 40篇 |
2017年 | 29篇 |
2016年 | 59篇 |
2015年 | 115篇 |
2014年 | 145篇 |
2013年 | 136篇 |
2012年 | 196篇 |
2011年 | 197篇 |
2010年 | 123篇 |
2009年 | 100篇 |
2008年 | 130篇 |
2007年 | 121篇 |
2006年 | 119篇 |
2005年 | 110篇 |
2004年 | 125篇 |
2003年 | 121篇 |
2002年 | 112篇 |
2001年 | 86篇 |
2000年 | 74篇 |
1999年 | 57篇 |
1998年 | 38篇 |
1997年 | 27篇 |
1996年 | 16篇 |
1995年 | 17篇 |
1994年 | 34篇 |
1993年 | 31篇 |
1992年 | 61篇 |
1991年 | 52篇 |
1990年 | 36篇 |
1989年 | 51篇 |
1988年 | 45篇 |
1987年 | 41篇 |
1986年 | 23篇 |
1985年 | 25篇 |
1984年 | 23篇 |
1983年 | 27篇 |
1982年 | 20篇 |
1980年 | 17篇 |
1979年 | 21篇 |
1978年 | 21篇 |
1977年 | 21篇 |
1976年 | 15篇 |
1974年 | 21篇 |
1973年 | 18篇 |
1972年 | 17篇 |
1970年 | 21篇 |
排序方式: 共有3183条查询结果,搜索用时 15 毫秒
61.
Multiple copies of genes coding for electron transport proteins in the bacterium Nitrosomonas europaea. 总被引:6,自引:4,他引:2
下载免费PDF全文
![点击此处可从《Journal of bacteriology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
H McTavish F LaQuier D Arciero M Logan G Mundfrom J A Fuchs A B Hooper 《Journal of bacteriology》1993,175(8):2445-2447
The genome of Nitrosomonas europaea contains at least three copies each of the genes coding for hydroxylamine oxidoreductase (HAO) and cytochrome c554. A copy of an HAO gene is always located within 2.7 kb of a copy of a cytochrome c554 gene. Cytochrome P-460, a protein that shares very unusual spectral features with HAO, was found to be encoded by a gene separate from the HAO genes. 相似文献
62.
Werner Sieghart Chike Item rea Buchstaller Karoline Fuchs Harald Höger Dieter Adamiker 《Journal of neurochemistry》1993,60(1):93-98
Abstract: Polyclonal antibodies were raised to synthetic peptides having amino acid sequences corresponding with the N- or C-terminal part of the γ-aminobutyric acidA (GABAA ) receptor α5 -subunit. These anti-peptide α5 (2–10) or anti-peptide α5 (427–433) antibodies reacted specifically with GABAA receptors purified from the brains of 5–10-day-old rats in an enzyme-linked immunosorbent assay and were able to dose-dependently immunoprecipitate up to 6.3 or 13.1% of the GABAA receptors present in the incubation, respectively. In immunoblots, each of these antibodies reacted with the same two protein bands with apparent molecular mass of 53 or 57 kDa. After exhaustive treatment of purified GABAA receptors with N -Glycanase, each of these antibodies identified two proteins with apparent molecular masses of 46 and 48 kDa. Additional treatment of GABAA receptors with neuraminidase and O -Glycanase resulted in an apparently single protein with molecular mass of 47 kDa, which again was identified by both the anti-peptide α5 (2–10) and the anti-peptide α5 (427–433) antibody. These results indicate the existence of at least two different α5 -sub-units of the GABAA receptor that differ in their carbohydrate content. In contrast to other α- or β-subunits of GABAA receptors so far investigated, at least one of these two α5 -subunits contains O-linked carbohydrates. 相似文献
63.
64.
EMBL-Search: a CD-ROM based database query system 总被引:1,自引:0,他引:1
This paper describes a system of generally applicable indexfiles provided on the EMBL sequence databases CDROM tofacilitate the development offronzend software to thesequence databases available on this CDROM. The indexfiles are used by a new versatile and userfriendly databaseretrieval program for the Apple Macintosh, EMBLSearch,which allows the easy construction of complex database queries.EMBLSearch utilizes crossreference informationcontained in the databases to support navigation between differentinformation resources. The ability to run EMBLSearchon a local computer network accessing a shared database CDROMmakes its use particularly cost effective. 相似文献
65.
Crevice-forming mutants in the rigid core of bovine pancreatic trypsin inhibitor: crystal structures of F22A, Y23A, N43G, and F45A. 总被引:4,自引:4,他引:0
下载免费PDF全文
![点击此处可从《Protein science : a publication of the Protein Society》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A. T. Danishefsky D. Housset K. S. Kim F. Tao J. Fuchs C. Woodward A. Wlodawer 《Protein science : a publication of the Protein Society》1993,2(4):577-587
Crystal structures of four mutants of bovine pancreatic trypsin inhibitor (F22A, Y23A, N43G, and F45A), engineered to alter their stability properties, have been determined. The mutated residues, which are highly conserved among Kunitz-type inhibitors, are located in the rigid core of the molecule. Replacement of the partially buried bulky residues of the wild-type protein with smaller residues resulted in crevices open to the exterior of the molecule. The overall three-dimensional structure of these mutants is very similar to that of the wild-type protein and only small rearrangements are observed among the atoms lining the crevices. 相似文献
66.
Yaoyu Ren Timo Danner Alexandra Moy Martin Finsterbusch Tanner Hamann Jan Dippell Till Fuchs Marius Müller Ricky Hoft André Weber Larry A. Curtiss Peter Zapol Matthew Klenk Anh T. Ngo Pallab Barai Brandon C. Wood Rongpei Shi Liwen F. Wan Tae Wook Heo Martin Engels Jagjit Nanda Felix H. Richter Arnulf Latz Venkat Srinivasan Jürgen Janek Jeff Sakamoto Eric D. Wachsman Dina Fattakhova-Rohlfing 《Liver Transplantation》2023,13(1):2201939
The garnet-type phase Li7La3Zr2O12 (LLZO) attracts significant attention as an oxide solid electrolyte to enable safe and robust solid-state batteries (SSBs) with potentially high energy density. However, while significant progress has been made in demonstrating compatibility with Li metal, integrating LLZO into composite cathodes remains a challenge. The current perspective focuses on the critical issues that need to be addressed to achieve the ultimate goal of an all-solid-state LLZO-based battery that delivers safety, durability, and pack-level performance characteristics that are unobtainable with state-of-the-art Li-ion batteries. This perspective complements existing reviews of solid/solid interfaces with more emphasis on understanding numerous homo- and heteroionic interfaces in a pure oxide-based SSB and the various phenomena that accompany the evolution of the chemical, electrochemical, structural, morphological, and mechanical properties of those interfaces during processing and operation. Finally, the insights gained from a comprehensive literature survey of LLZO–cathode interfaces are used to guide efforts for the development of LLZO-based SSBs. 相似文献
67.
Ilana Agmon Tamar Auerbach David Baram Heike Bartels Anat Bashan Rita Berisio Paola Fucini Harly A S Hansen Joerg Harms Maggie Kessler Moshe Peretz Frank Schluenzen Ada Yonath Raz Zarivach 《European journal of biochemistry》2003,270(12):2543-2556
High-resolution crystal structures of large ribosomal subunits from Deinococcus radiodurans complexed with tRNA-mimics indicate that precise substrate positioning, mandatory for efficient protein biosynthesis with no further conformational rearrangements, is governed by remote interactions of the tRNA helical features. Based on the peptidyl transferase center (PTC) architecture, on the placement of tRNA mimics, and on the existence of a two-fold related region consisting of about 180 nucleotides of the 23S RNA, we proposed a unified mechanism integrating peptide bond formation, A-to-P site translocation, and the entrance of the nascent protein into its exit tunnel. This mechanism implies sovereign, albeit correlated, motions of the tRNA termini and includes a spiral rotation of the A-site tRNA-3' end around a local two-fold rotation axis, identified within the PTC. PTC features, ensuring the precise orientation required for the A-site nucleophilic attack on the P-site carbonyl-carbon, guide these motions. Solvent mediated hydrogen transfer appears to facilitate peptide bond formation in conjunction with the spiral rotation. The detection of similar two-fold symmetry-related regions in all known structures of the large ribosomal subunit, indicate the universality of this mechanism, and emphasizes the significance of the ribosomal template for the precise alignment of the substrates as well as for accurate and efficient translocation. The symmetry-related region may also be involved in regulatory tasks, such as signal transmission between the ribosomal features facilitating the entrance and the release of the tRNA molecules. The protein exit tunnel is an additional feature that has a role in cellular regulation. We showed by crystallographic methods that this tunnel is capable of undergoing conformational oscillations and correlated the tunnel mobility with sequence discrimination, gating and intracellular regulation. 相似文献
68.
69.
H. B. Lee J. Guillaume R. Chou G. Cuzon H. H. Heng J. Fuchs 《Zeitschrift fur angewandte Ichthyologie》1995,11(3-4):302-308
This paper describes the effort of the Marine Aquaculture Section of the Primary Production Department in Singapore and the Institut Francais de Recherche pour l'Exploitation de la Mer in developing adequate facilities for fish nutritional requirement studies in Singapore, and in introducing appropriate nutritional methodology so that results are reliable and accurate. One of the first achievements was the demonstration of homogeneous fish (tropical seabass, Lates calcarifer Bloch) growth response in a newly established tank system before any nutritional experiments were initiated. The application of statistical procedures that take into consideration the power of a test and number of replications required has allowed for more accurate interpretation of results. This can be seen in the results of the first nutritional requirement experiment on the optimal dietary protein level of the seabass at constant energy. 相似文献
70.
Two distinct models account for short and long deletions within sequence repeats in Escherichia coli.
下载免费PDF全文
![点击此处可从《Journal of bacteriology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
In Escherichia coli, (GpC)n sequences cloned into plasmid DNA molecules are deletion-prone with the occurrence of both short (<2 bp) and long (>2 bp) deletion events. These repetitive tracts can be stabilized by interrupting the strict monotony of the repetition with a variant dinucleotide sequence. The stabilization of short deletion events that is mediated by the variant sequence is completely lost in E. coli mismatch repair-deficient strains. In contrast, this repair pathway has no influence on the frequency of occurrence of long deletion events, even in sequences containing the variant repeat. These results lead us to propose two distinct models to account for short and long deletions within repetitive sequences in E. coli. Furthermore, this study reveals that the deletions occur preferentially at the end of the repeat sequence that is distal with respect to the origin of replication. 相似文献