全文获取类型
收费全文 | 258篇 |
免费 | 11篇 |
专业分类
269篇 |
出版年
2024年 | 2篇 |
2022年 | 4篇 |
2021年 | 9篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 10篇 |
2015年 | 19篇 |
2014年 | 15篇 |
2013年 | 14篇 |
2012年 | 10篇 |
2011年 | 20篇 |
2010年 | 14篇 |
2009年 | 10篇 |
2008年 | 25篇 |
2007年 | 17篇 |
2006年 | 23篇 |
2005年 | 14篇 |
2004年 | 12篇 |
2003年 | 10篇 |
2002年 | 13篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1990年 | 1篇 |
1988年 | 2篇 |
1983年 | 2篇 |
1982年 | 1篇 |
排序方式: 共有269条查询结果,搜索用时 0 毫秒
181.
Takamasa Tobimatsu Tsuneo Nishiki Masaya Morimoto Ryou Miyata Tetsuo Toraya 《Archives of microbiology》2009,191(3):199-206
Coenzyme B12-dependent diol and glycerol dehydratases are isofunctional enzymes, which catalyze dehydration of 1, 2-diols to produce corresponding
aldehydes. Although the two types of dehydratases have high sequence homology, glycerol dehydratase is a soluble cytosolic
enzyme, whereas diol dehydratase is a low-solubility enzyme associated with carboxysome-like polyhedral organelles. Since
both the N-terminal 20 and 16 amino acid residues of the β and γ subunits, respectively, are indispensable for the low solubility
of diol dehydratase, we constructed glycerol dehydratase-based chimeric enzymes which carried N-terminal portions of the β
and γ subunits of diol dehydratase in the corresponding subunits of glycerol dehydratase. Addition of the diol dehydratase-specific
N-terminal 34 and 33 amino acid residues of the β and γ subunits, respectively, was not enough to lower the solubility of
glycerol dehydratase. A chimeric enzyme which carries the low homology region (residues 35–60) of the diol dehydratase β subunit
in addition to the diol dehydratase-specific extra-regions of β and γ subunits showed low solubility comparable to diol dehydratase,
although its hydropathy plot does not show any prominent hydrophobic peaks in these regions. It was thus concluded that short
N-terminal sequences are sufficient to change the solubility of the enzyme. 相似文献
182.
Yajima S Nakanishi K Takahashi K Ogawa T Hidaka M Kezuka Y Nonaka T Ohsawa K Masaki H 《Biochemical and biophysical research communications》2004,322(3):966-973
Colicin D is a plasmid-encoded proteinaceous toxin which kills sensitive Escherichia coli. Toxicity stems from ribonuclease activity that targets exclusively four isoacceptors of tRNA(Arg) with a cleavage position between 38 and 39 of the corresponding anticodons. Since no other tRNAs with the same sequences at 38 and 39 as tRNA(Arg)s are cleaved, colicin D should be capable of recognizing some higher order structure of tRNAs. We report here two crystal structures of catalytic domains of colicin D which have different N-terminal lengths, both complexed with its cognate inhibitor protein, ImmD. A row of positive charge patches is found on the surface of the catalytic domain, suggestive of the binding site of the tRNAs. This finding, together with our refined tRNase activity experiments, indicates that the catalytic domain starting at position 595 has activity almost equivalent to that of colicin D. 相似文献
183.
184.
185.
Thermodynamic characterization of OsGID1-gibberellin binding using calorimetry and docking simulations 总被引:1,自引:0,他引:1
Xiang H Takeuchi H Tsunoda Y Nakajima M Murata K Ueguchi-Tanaka M Kidokoro S Kezuka Y Nonaka T Matsuoka M Katoh E 《Journal of molecular recognition : JMR》2011,24(2):275-282
Gibberellins (GAs) are phytohormones regulating various developmental processes in plants. In rice, the initial GA-signaling events involve the binding of a GA to the soluble GA receptor protein, GID1. Although X-ray structures for certain GID1/GA complexes have recently been determined, an examination of the complexes does not fully clarify how GID1s discriminate among different GAs. Herein, we present a study aimed at defining the types of forces important to binding via a combination of isothermal titration calorimetry (ITC) and computational docking studies that employed rice GID1 (OsGID1), OsGID1 mutants, which were designed to have a decreased possible number of hydrogen bonds with bound GA, and GA variants. We find that, in general, GA binding is enthalpically driven and that a hydrogen bond between the phenolic hydroxyl of OsGID1 Tyr134 and the C-3 hydroxyl of a GA is a defining structural element. A hydrogen-bond network that involves the C-6 carboxyl of a GA that directly hydrogen bonds the hydroxyl of Ser198 and indirectly, via a two-water-molecule network, the phenolic hydroxyl of Tyr329 and the NH of the amide side-chain of Asn255 is also important for GA binding. The binding of OsGID1 by GA(1) is the most enthalpically driven association found for the biologically active GAs evaluated in this study. This observation might be a consequence of a hydrogen bond formed between the hydroxyl at the C-13 position of GA(1) and the main chain carbonyl of OsGID1 Phe245. Our results demonstrate that by combining ITC experiments and computational methods much can be learned about the thermodynamics of ligand/protein binding. 相似文献
186.
Takamasa Harada Joe Swift Jerome Irianto Jae-Won Shin Kyle R. Spinler Avathamsa Athirasala Rocky Diegmiller P.C. Dave P. Dingal Irena L. Ivanovska Dennis E. Discher 《The Journal of cell biology》2014,204(5):669-682
Cell migration through solid tissue often involves large contortions of the nucleus, but biological significance is largely unclear. The nucleoskeletal protein lamin-A varies both within and between cell types and was shown here to contribute to cell sorting and survival in migration through constraining micropores. Lamin-A proved rate-limiting in 3D migration of diverse human cells that ranged from glioma and adenocarcinoma lines to primary mesenchymal stem cells (MSCs). Stoichiometry of A- to B-type lamins established an activation barrier, with high lamin-A:B producing extruded nuclear shapes after migration. Because the juxtaposed A and B polymer assemblies respectively conferred viscous and elastic stiffness to the nucleus, subpopulations with different A:B levels sorted in 3D migration. However, net migration was also biphasic in lamin-A, as wild-type lamin-A levels protected against stress-induced death, whereas deep knockdown caused broad defects in stress resistance. In vivo xenografts proved consistent with A:B-based cell sorting, and intermediate A:B-enhanced tumor growth. Lamins thus impede 3D migration but also promote survival against migration-induced stresses. 相似文献
187.
Xiaomei T. Kuang Xiaoguang Li Gursev Anmole Philip Mwimanzi Aniqa Shahid Anh Q. Le Louise Chong Hua Qian Toshiyuki Miura Tristan Markle Bemuluyigza Baraki Elizabeth Connick Eric S. Daar Heiko Jessen Anthony D. Kelleher Susan Little Martin Markowitz Florencia Pereyra Eric S. Rosenberg Bruce D. Walker Takamasa Ueno Zabrina L. Brumme Mark A. Brockman 《Journal of virology》2014,88(17):10200-10213
188.
189.
Hiroshi Nakano Yoko Shibata Sumito Inoue Akira Igarashi Keiko Yamauchi Shuichi Abe Masamichi Sato Yasuko Aida Keiko Nunomiya Tomomi Kimura Takako Nemoto Tetsu Watanabe Tsuneo Konta Yoshiyuki Ueno Takeo Kato Takamasa Kayama Isao Kubota 《PloS one》2013,8(12)
Background
Accumulating evidence suggests the involvement of an autoimmune mechanism in the pathogenesis of respiratory dysfunction. The aim of this study was to investigate the relationship between pulmonary function and serum antibodies to several connective tissue disease autoantigens (ACTDA) levels, which has not been investigated in a general population.Methods
Blood sampling and spirometry were performed for subjects (n = 3,257) aged ≥40 years who participated in a community-based annual health check in Takahata, Japan, from 2004 to 2006. ACTDA was measured by enzyme immunoassay, and subjects with ACTDA values ≥20 were defined as positive.Results
In males, there were significant inverse relationships between logarithmically transformed ACTDA values and spirometric parameters, including % predicted values for forced expiratory volume in 1 s (FEV1) and maximal midexpiratory flow (MMF) as well as FEV1/forced vital capacity (FVC). Multiple linear regression analysis revealed that except for the relationship between ACTDA and FEV1/FVC, these relationships were still significant after adjustment for Brinkman index (a measure of inhaled cigarette consumption). The prevalence of positive ACTDA was greater in male never-smokers with mixed ventilation disorders and relatively severe airflow obstruction (% predicted FEV1 below the median value).Conclusions
Autoimmunity may be involved in the mechanism of impaired pulmonary function in the general population. 相似文献190.