全文获取类型
收费全文 | 160篇 |
免费 | 14篇 |
出版年
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 3篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 5篇 |
2014年 | 6篇 |
2013年 | 5篇 |
2012年 | 12篇 |
2011年 | 4篇 |
2010年 | 4篇 |
2009年 | 3篇 |
2008年 | 8篇 |
2007年 | 12篇 |
2006年 | 5篇 |
2005年 | 4篇 |
2004年 | 9篇 |
2003年 | 5篇 |
2002年 | 10篇 |
2001年 | 4篇 |
2000年 | 8篇 |
1999年 | 4篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1992年 | 2篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 6篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 3篇 |
1975年 | 5篇 |
1974年 | 2篇 |
1973年 | 5篇 |
1972年 | 1篇 |
1971年 | 3篇 |
1970年 | 6篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1946年 | 1篇 |
1942年 | 1篇 |
排序方式: 共有174条查询结果,搜索用时 46 毫秒
71.
Marcia Berrêdo-Pinho Dario E Kalume Paloma R Correa Leonardo HF Gomes Melissa P Pereira Renata F da Silva Luiz RR Castello-Branco Wim M Degrave Leila Mendonça-Lima 《BMC microbiology》2011,11(1):80
Background
Bacille Calmette-Guerin (BCG) is currently the only available vaccine against tuberculosis (TB) and comprises a heterogeneous family of sub-strains with genotypic and phenotypic differences. The World Health Organization (WHO) affirms that the characterization of BCG sub-strains, both on genomic and proteomic levels, is crucial for a better comprehension of the vaccine. In addition, these studies can contribute in the development of a more efficient vaccine against TB. Here, we combine two-dimensional electrophoresis (2DE) and mass spectrometry to analyse the proteomic profile of culture filtrate proteins (CFPs) from M. bovis BCG Moreau, the Brazilian vaccine strain, comparing it to that of BCG Pasteur. CFPs are considered of great importance given their dominant immunogenicity and role in pathogenesis, being available for interaction with host cells since early infection. 相似文献72.
Tetrachlorohydroquinone (TCHQ) dehalogenase is profoundly inhibited by its aromatic substrates, TCHQ and trichlorohydroquinone (TriCHQ). Surprisingly, mutations that change Ile12 to either Ser or Ala give an enzyme that shows no substrate inhibition. We have previously shown that TriCHQ is a noncompetitive inhibitor of the thiol-disulfide exchange reaction between glutathione and ESSG, a covalent adduct between Cys13 and glutathione formed during dehalogenation of the substrate. Substrate inhibition of the thiol-disulfide exchange reaction is less severe in the I12S and I12A mutant enzymes, primarily due to weaker binding of TriCHQ to ESSG. These mutations also result in a decrease in the rate of dehalogenation. Because the rate-limiting step in the I12S and I12A enzymes is dehalogenation, rather than the thiol-disulfide exchange reaction, the relatively modest inhibition of the thiol-disulfide exchange reaction does not affect the overall rate of turnover. 相似文献
73.
74.
MotifCluster finds related motifs in a set of sequences, and clusters the sequences into families using the motifs they contain.
MotifCluster, at , lets users test whether proteins are related, cluster sequences by shared conserved motifs, and visualize motifs mapped
onto trees, sequences and three-dimensional structures. We demonstrate MotifCluster's accuracy using gold-standard protein
superfamilies; using recommended settings, families were assigned to the correct superfamilies with 0.17% false positive and
no false negative assignments. 相似文献
75.
Anton?C?van de Vusse Suzanne?GM?Stomp-van den Berg Alfons?HF?Kessels Wim?EJ?WeberEmail author 《BMC neurology》2004,4(1):13
Background
Complex Regional Pain Syndrome type one (CRPS I) or formerly Reflex Sympathetic Dystrophy (RSD) is a disabling syndrome, in which a painful limb is accompanied by varying symptoms. Neuropathic pain is a prominent feature of CRPS I, and is often refractory to treatment. Since gabapentin is an anticonvulsant with a proven analgesic effect in various neuropathic pain syndromes, we sought to study the efficacy of the anticonvulsant gabapentin as treatment for pain in patients with CRPS I. 相似文献76.
Background
Glutathione is found primarily in eukaryotes and in Gram-negative bacteria. It has been proposed that eukaryotes acquired the genes for glutathione biosynthesis from the alpha-proteobacterial progenitor of mitochondria. To evaluate this, we have used bioinformatics to analyze sequences of the biosynthetic enzymes γ-glutamylcysteine ligase and glutathione synthetase. 相似文献77.
The secreted signaling protein Wingless acts as a morphogen to pattern the imaginal discs of Drosophila. Here we report identification of a secreted repressor of Wingless activity, which we call Notum. Loss of Notum function leads to increased Wingless activity by altering the shape of the Wingless protein gradient. When overexpressed, Notum blocks Wingless activity. Notum encodes a member of the alpha/beta-hydrolase superfamily, with similarity to pectin acetylesterases. We present evidence that Notum influences Wingless protein distribution by modifying the heparan sulfate proteoglycans Dally-like and Dally. High levels of Wingless signaling induce Notum expression. Thus, Wingless contributes to shaping its own gradient by regulating expression of a protein that modifies its interaction with cell surface proteoglycans. 相似文献
78.
We provide statistically reliable sequence evidence indicating that at least 12 of 23 SCOP (betaalpha)(8) (TIM) barrel superfamilies share a common origin. This includes all but one of the known and predicted TIM barrels found in central metabolism. The statistical evidence is complemented by an examination of the details of protein structure, with certain structural locations favouring catalytic residues even though the nature of their molecular function may change. The combined analysis of sequence, structure and function also enables us to propose a phylogeny of TIM barrels. Based on these data, we are able to examine differing theories of pathway and enzyme evolution, by mapping known TIM barrel folds to the pathways of central metabolism. The results favour widespread recruitment of enzymes between pathways, rather than a "backwards evolution" model, and support the idea that modern proteins may have arisen from common ancestors that bound key metabolites. 相似文献
79.
Beall MS Copley LA Niemann JJ Lankachandra K Williams JL 《Journal of biomechanics》2007,40(5):1137-1144
Rigid immobilization of the cervical spine in children is normally accomplished with a halo ring attached to the skull with pins. Concern exists about the risk of halo pin complications in small children due to their diminished skull thickness. More data are needed on biomechanical properties of the immature skull and on safe levels for halo pin penetration forces. The study included halo pin penetration tests on 43 skull samples obtained from eight fetal calves, radial compression tests of 11 skull samples, and histology. Compressive composite elastic modulus (15-139MPa), yield stress (1-5MPa) and composite consolidation modulus (188-479MPa) were measured in the skull's radial direction. Pin penetration force (F) in Newtons at a pin-penetration depth equal to the original skull thickness (T) in mm, was related to T as: F=100+4.3e(T) (R(2)=0.76, p<0.0001). However, the 95% confidence limits on individual predictions were wide, e.g., 0-475MPa for T=1.5mm and 0-700MPa for T=4mm. These results suggest that skull thickness cannot be reliably used to predict halo pin penetration loads in a skull with similar structural and mechanical properties to that of the fetal calf. Due to the lack of available human data for comparison, the relevance of using the fetal calf skull as a model for human infants and young children remains inconclusive. Clinical recommendations regarding pediatric halo pin penetration loads cannot be made without further study of children's skull structure and biomechanical properties. 相似文献
80.
Thomas M Wishart Stephen HF MacDonald Philip E Chen Michael J Shipston Michael P Coleman Thomas H Gillingwater Richard R Ribchester 《Molecular neurodegeneration》2007,2(1):1-6