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681.
Probiotics and Antimicrobial Proteins - Probiotic health benefits are strain specific and are dose dependent. Hence, administering the correct strains, at the recommended doses is essential to... 相似文献
682.
Hala E. M. Tolan Wael A. El-Sayed Nashwa Tawfek Farouk M. E. Abdel-Megeid Omnya M. Kutkat 《Nucleosides, nucleotides & nucleic acids》2020,39(5):649-670
AbstractNew 1,2,3-triazole glycosides and 1,2,4-thioglycosides incorporating a substituted pyrimidinedione ring system were synthesized via click dipolar cycloaddition and heterocyclization of hydrazine-1-carbodithioate derivatives, respectively. The sugar hydrazine derivatives linked aminodimethyluracil were also prepared. In addition, the oxadiazoline substituted with acyclic sugar moieties linked to the pyrimidinedione as acyclic nucleoside analogs were synthesized. The antiviral activity of the synthesized compounds against avian influenza H5N1 virus was investigated and compounds 18, 13 and 19 showed good activities against the virus strains. 相似文献
683.
Bacterial classification with convolutional neural networks based on different data reduction layers
Samia M. Abd –Alhalem Naglaa F. Soliman S. E. Abd Elrahman Nabil A. Ismail El-Sayed M. El-Rabaie 《Nucleosides, nucleotides & nucleic acids》2020,39(4):493-503
AbstractFor high accuracy classification of DNA sequences through Convolutional Neural Networks (CNNs), it is essential to use an efficient sequence representation that can accelerate similarity comparison between DNA sequences. In addition, CNN networks can be improved by avoiding the dimensionality problem associated with multi-layer CNN features. This paper presents a new approach for classification of bacterial DNA sequences based on a custom layer. A CNN is used with Frequency Chaos Game Representation (FCGR) of DNA. The FCGR is adopted as a sequence representation method with a suitable choice of the frequency k-lengthen words occurrence in DNA sequences. The DNA sequence is mapped using FCGR that produces an image of a gene sequence. This sequence displays both local and global patterns. A pre-trained CNN is built for image classification. First, the image is converted to feature maps through convolutional layers. This is sometimes followed by a down-sampling operation that reduces the spatial size of the feature map and removes redundant spatial information using the pooling layers. The Random Projection (RP) with an activation function, which carries data with a decent variety with some randomness, is suggested instead of the pooling layers. The feature reduction is achieved while keeping the high accuracy for classifying bacteria into taxonomic levels. The simulation results show that the proposed CNN based on RP has a trade-off between accuracy score and processing time. 相似文献
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685.
El-Sayyad Gharieb S. El-Bastawisy Hanan S. Gobara Mohamed El-Batal Ahmed I. 《Biological trace element research》2020,195(1):323-342
Biological Trace Element Research - The purpose of this research is to compare and enhance the antimicrobial and antibiofilm potentials of the biogenic selenium nanoparticles (Se NPs) produced by... 相似文献
686.
The Everglades freshwater marl prairie is a dynamic and spatially heterogeneous landscape, containing thousands of tree islands
nested within a marsh matrix. Spatial processes underlie population and community dynamics across the mosaic, especially the
balance between woody and graminoid components, and landscape patterns reflect interactions among multiple biotic and abiotic
drivers. To better understand these complex, multi-scaled relationships we employed a three-tiered hierarchical design to
investigate the effects of seed source, hydrology, and more indirectly fire on the establishment of new woody recruits in
the marsh, and to assess current tree island patterning across the landscape. Our analyses were conducted at the ground level
at two scales, which we term the micro- and meso-scapes, and results were related to remotely detected tree island distributions
assessed in the broader landscape, that is, the macro-scape. Seed source and hydrologic effects on recruitment in the micro-
and meso-scapes were analyzed via logistic regression, and spatial aggregation in the macro-scape was evaluated using a grid-based
univariate O-ring function. Results varied among regions and scales but several general trends were observed. The patterning
of adult populations was the strongest driver of recruitment in the micro- and meso-scape prairies, with recruits frequently
aggregating around adults or tree islands. However in the macro-scape biologically associated (second order) aggregation was
rare, suggesting that emergent woody patches are heavily controlled by underlying physical and environmental factors such
as topography, hydrology, and fire. 相似文献
687.
Gustine Rebecca N. Hanan Erin J. Robichaud Peter R. Elliot William J. 《Biogeochemistry》2022,157(1):51-68
Biogeochemistry - Wildfire is a major driver of nitrogen (N) cycling and export from terrestrial to aquatic systems. While fire is a natural process in many watersheds, it can still degrade water... 相似文献
688.
Eman A. Sayed Gamal Badr Khadiga Abdel-Hameed Hassan Hanan Waly Betul Ozdemir Mohamed H. Mahmoud Salman Alamery 《Saudi Journal of Biological Sciences》2021,28(2):1272-1282
In an animal models, carbon tetrachloride (CCl4) is a carcinogenic agent that causes liver fibrosis. The current study aims to investigate whether induction in liver-fibrosis by CCl4 in the mouse model could promote the initiation of fibrosis in lymph node and spleen due to sustained increase of inflammatory signals and also aimed to clarify the protective therapeutic effects of propolis. The male mice (BALB/c) were categorized into three experimental sets and each group involved 15 mice. Control group falls into first group; group-II and group-III were injected with CCl4 to induce liver-fibrosis and oral supplementation with propolis was provided in group-III for 4-weeks. A major improvement with hepatic collagen and α-smooth muscle actin (α-SMA) production was aligned with the activation of liver fibrosis from CCl4. Mice treated with CCl4 exhibited collagen deposition towards liver sections, pathological alterations in spleen and lymph node architectures, and a significantly increase the circulation of both T&B cells in secondary lymphoid organs. Mechanically, the secondary lymphoid organs treated with CCl4 in mice exposed a positive growth in α-SMA and collagen expression, increased in proinflammatory cytokine levels and a significant increase in TGF-β, NO and ROS levels. A manifest intensification in the expression of Nrf2, COX-2, and eNOS and upregulation of ASK1 and P38 phosphorylation. Interestingly, addition of propolis-treated CCl4 mice, substantially suppressed deposition of liver collagen, repealed inflammatory signals and resorted CCl4-mediated alterations in signaling cascades, thereby repairing the architectures of the secondary lymphoid organs. Our findings revealed benefits of propolis against fibrotic complications and enhancing secondary lymphoid organ architecture. 相似文献
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