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61.
Natalia M. Astakhova Andrey A. Perelygin Andrey A. Zharkikh Teri L. Lear Stephen J. Coleman James N. MacLeod Margo A. Brinton 《Immunogenetics》2009,61(7):529-539
Toll-like receptors 3, 7, and 8 (TLR3, TLR7, and TLR8) were studied in the genomes of the domestic horse and several other
mammals. The messenger RNA sequences and exon/intron structures of these TLR genes were determined. An equine bacterial artificial
chromosome clone containing the TLR3 gene was assigned by fluorescent in situ hybridization to the horse chromosomal location
ECA27q16–q17 and this map location was confirmed using an equine radiation hybrid panel. Direct sequencing revealed 13 single-nucleotide
polymorphisms in the coding regions of the equine TLR 3, 7, and 8 genes. Of these polymorphisms, 12 were not previously reported.
The allelic frequency was estimated for each single-nucleotide polymorphism from genotyping data obtained for 154 animals
from five horse breeds. Some of these frequencies varied significantly among different horse breeds. Domain architecture predictions
for the three equine TLR protein sequences revealed several conserved regions within the variable leucine-rich repeats between
the corresponding horse and cattle TLR proteins. A phylogenetic analysis did not indicate that any significant exchanges had
occurred between paralogous TLR7 and TLR8 genes in 20 vertebrate species analyzed.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
62.
Wilson S Hamilton MA Hamilton GC Schumann MR Stoodley P 《Applied and environmental microbiology》2004,70(10):5847-5852
The detachment of cells from bacterial biofilms is an important, yet poorly understood and largely unquantified phenomenon. Detached cell clumps from medical devices may form microemboli and lead to metastasis, especially if they are resistant to host defenses and antibiotics. In manufacturing plants detached clumps entering a process stream decrease product quality. Two strains of Pseudomonas aeruginosa, a wild type (PAO1) and a cell signaling mutant (JP1), were studied to (i) quantify and model detachment patterns and (ii) determine the influence of cell signaling on detachment. We collected effluent from a biofilm flowthrough reactor and determined the size distribution for cell detachment events by microscopic examination and image analysis. The two strains were similar in terms of both biofilm structure and detachment patterns. Most of the detachment events were single-cell events; however, multiple-cell detachment events contributed a large fraction of the total detached cells. The rates at which events containing multiple cells detached from the biofilm were estimated by fitting a statistical model to the size distribution data. For events consisting of at least 1,000 cells, the estimated rates were 4.5 events mm(-2) min(-1) for PAO1 and 4.3 events mm(-2) min(-1) for JP1. These rates may be significant when they are scaled up to the total area of a real biofilm-contaminated medical device surface and to the hours or days of patient exposure. 相似文献
63.
Elastic proteins: biological roles and mechanical properties 总被引:7,自引:0,他引:7
Gosline J Lillie M Carrington E Guerette P Ortlepp C Savage K 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2002,357(1418):121-132
The term 'elastic protein' applies to many structural proteins with diverse functions and mechanical properties so there is room for confusion about its meaning. Elastic implies the property of elasticity, or the ability to deform reversibly without loss of energy; so elastic proteins should have high resilience. Another meaning for elastic is 'stretchy', or the ability to be deformed to large strains with little force. Thus, elastic proteins should have low stiffness. The combination of high resilience, large strains and low stiffness is characteristic of rubber-like proteins (e.g. resilin and elastin) that function in the storage of elastic-strain energy. Other elastic proteins play very different roles and have very different properties. Collagen fibres provide exceptional energy storage capacity but are not very stretchy. Mussel byssus threads and spider dragline silks are also elastic proteins because, in spite of their considerable strength and stiffness, they are remarkably stretchy. The combination of strength and extensibility, together with low resilience, gives these materials an impressive resistance to fracture (i.e. toughness), a property that allows mussels to survive crashing waves and spiders to build exquisite aerial filters. Given this range of properties and functions, it is probable that elastic proteins will provide a wealth of chemical structures and elastic mechanisms that can be exploited in novel structural materials through biotechnology. 相似文献
64.
Baele M Vaneechoutte M Verhelst R Vancanneyt M Devriese LA Haesebrouck F 《Journal of microbiological methods》2002,50(3):263-271
tDNA intergenic spacer PCR (tDNA-PCR) using consensus primers complementary to the conserved edges of the tRNA genes can amplify the intergenic spacers. Separation of the PCR products with capillary electrophoresis enables discrimination between fragments differing only one basepair in length. This method was applied to a collection of 82 Lactobacillus strains belonging to 37 species in order to evaluate the discriminatory power of this technique within this genus. Twenty-one species could be distinguished to species level on the basis of a unique tDNA fingerprint pattern. The other species grouped by two (e.g. L. fermentum and L. cellobiosus) or three (L. acidophilus, L. gallinarum and L. helveticus). Inclusion of the resulting fingerprints in a numerical database containing fingerprints of numerous other Gram-positive and Gram-negative species makes the identification of unknown strains possible. 相似文献
65.
Lauer RT Stackhouse C Shewokis PA Smith BT Orlin M McCarthy JJ 《Journal of biomechanics》2005,38(6):1351-1357
The objective of this study was to examine the use of the continuous wavelet transform (CWT) on surface electromyographic (sEMG) signals acquired from the lower extremity muscles during gait in children with typical development (TD) and cerebral palsy (CP). This was done to explore the possibility of developing a quantitative assessment scale of motor function based on time-frequency information. An initial study was conducted on retrospective gait data from three children, matched in gender and in anthropometric variables but with differing levels of walking ability. EMG data were extracted from five lower extremity muscles to assess the degrees of differentiation. The data were processed using the CWT to derive an average scalogram, from which the instantaneous mean frequency (IMNF) was calculated. Principal component analysis was used to assess the differences between the curves. Preliminary results indicated that for select lower extremity muscles, there was a significant deviation in the IMNF curves in the child with CP as compared to the child with TD. Furthermore, as motor impairment increased, total percent explained variance to the TD curves decreased. This suggests that it might be possible to derive a physiologically based quantitative index for assessing motor function and for assessing clinical treatments in CP using the wavelet analysis. 相似文献
66.
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68.
Shan Shan Qi Alexander Bogdanov Margo Cnockaert Tessa Acar Sarah Ranty-Roby Tom Coenye Peter Vandamme Gabriele M. König Max Crüsemann Aurélien Carlier 《Environmental microbiology》2021,23(4):2132-2151
A diverse set of bacteria live on the above-ground parts of plants, composing the phyllosphere, and play important roles for plant health. Phyllosphere microbial communities assemble in a predictable manner and diverge from communities colonizing other plant organs or the soil. However, how these communities differ functionally remains obscure. We assembled a collection of 258 bacterial isolates representative of the most abundant taxa of the phyllosphere of Arabidopsis and a shared soil inoculum. We screened the collection for the production of metabolites that inhibit the growth of Gram-positive and Gram-negative bacteria either in isolation or in co-culture. We found that isolates capable of constitutive antibiotic production in monoculture were significantly enriched in the soil fraction. In contrast, the proportion of binary cultures resulting in the production of growth inhibitory compounds differed only marginally between the phyllosphere and soil fractions. This shows that the phyllosphere may be a rich resource for potentially novel molecules with antibiotic activity, but that production or activity is dependent upon induction by external signals or cues. Finally, we describe the isolation of antimicrobial acyloin metabolites from a binary culture of Arabidopsis phyllosphere isolates, which inhibit the growth of clinically relevant Acinetobacter baumannii. 相似文献
69.
Hemant K. Roy Charles B. Brendler Hariharan Subramanian Di Zhang Charles Maneval John Chandler Leah Bowen Karen L. Kaul Brian T. Helfand Chi-Hsiung Wang Margo Quinn Jacqueline Petkewicz Michael Paterakos Vadim Backman 《PloS one》2015,10(2)
PurposeTo determine whether nano-architectural interrogation of prostate field carcinogenesis can be used to predict prognosis in patients with early stage (Gleason 6) prostate cancer (PCa), which is mostly indolent but frequently unnecessarily treated.ResultsThere was a profound increase in nano-architectural disorder between progressors and non-progressors. Indeed, the Ld from future progressors was dramatically increased when compared to future non-progressors (1±0.065 versus 1.30±0.0614, respectively p = 0.002). The area under the receiver operator characteristic curve (AUC) was 0.79, yielding a sensitivity of 88% and specificity of 72% for discriminating between progressors and non-progressors. This was not confounded by demographic factors (age, smoking status, race, obesity), thus supporting the robustness of the approach.ConclusionsWe demonstrate, for the first time, that nano-architectural alterations occur in prostate cancer field carcinogenesis and can be exploited to predict prognosis of early stage PCa. This approach has promise in addressing the clinically vexing dilemma of management of Gleason 6 PCa and may provide a paradigm for dealing with the larger issue of cancer overdiagnosis. 相似文献
70.
Margo M. C. van Mol Erwin J. O. Kompanje Dominique D. Benoit Jan Bakker Marjan D. Nijkamp 《PloS one》2015,10(8)