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Bulusu Jagannadh Kondalu R. Dharshna Priya Laveti Chandini Devi Gopiparthi Kranthi Sri 《Journal of molecular modeling》2010,16(2):285-290
The result of an exhaustive search of low-energy conformers of 1,4,7,10,13-Pentaoxacyclopentadecane is presented. The search
method combines the generation of large number of trial conformers using local nonstochastic deformations known as the Conflex
method, which is coupled to AMBER force field as the minimizer. The extent of the conformational space sampled was evaluated
from the view point of the number of duplicates of each conformer, generation of inclusion type structures without considering
the substrate and the spread of the allowed torsion angles visited during the search. It is shown that the conformational
search is exhaustive and efficient as conformers, which the metal coordinated crown ether complexes adopt, were generated.
Free energies using the AMBER structures were calculated using the model of Cramer and Truhlar. The study suggests that 1,4,7,10,13-Pentaoxacyclopentadecane
exists as a mixture of conformers in solution. The results show the efficiency of the method and could be the method of choice
in the design of synthetic macrocyclic receptors. 相似文献
63.
Mehar H. Asif Shrikant S. Mantri Ayush Sharma Anukool Srivastava Ila Trivedi Priya Gupta Chandra S. Mohanty Samir V. Sawant Rakesh Tuli 《Tree Genetics & Genomes》2010,6(6):941-952
Jatropha curcas is an important non-edible oil seed tree species and is considered a promising source of biodiesel. The complete nucleotide
sequence of J. curcas chloroplast genome (cpDNA) was determined by pyrosequencing and gaps filled by Sanger sequencing. The cpDNA is a circular
molecule of 163,856 bp in length and codes for 110 distinct genes (78 protein coding, four rRNA and 28 distinct tRNA). Genome
organisation and arrangement are similar to the reported angiosperm chloroplast genome. However, in Jatropha, the infA and the rps16 genes are non-functional. The inverted repeat (IR) boundary is within the rpl2 gene, and the 13 nucleotides at the ends of the two duplicate genes are different. Repeat analysis suggests the presence
of 72 repeat regions (>30 bp) apart from the IR; of these, 48 were direct and 24 were palindromic repeats. Phylogenetic analysis
of 81 protein coding chloroplast genes from 65 taxa by maximum parsimony, maximum likelihood and minimum evolution analyses
at 100 bootstraps provide strong support for the placement of inaperturate crotonoids of which Jatropha is a member as sister to articulated crotonoids of which Manihot is a member. 相似文献
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The diversity population of microorganisms with the capability to use selenate as a terminal electron acceptor, reducing it to selenite and elemental selenium by the process known as dissimilatory selenate reduction, is largely unknown. The overall objective of this study was to gain an in-depth understanding of anaerobic biotransformation of selenium in the environment, particularly anaerobic respiration, and to characterize the microorganisms catalyzing this process. Here, we demonstrate the isolation and characterization of four novel anaerobic dissimilatory selenate-respiring bacteria enriched from a variety of sources, including sediments from three different water bodies in Chennai, India, and a tidal estuary in New Jersey. Strains S5 and S7 from India, strain KM from the Meadowlands, NJ, and strain pn1, categorized as a laboratory contaminant, were all phylogenetically distinct, belonging to various phyla in the bacterial domain. The 16S rRNA gene sequence shows that strain S5 constitutes a new genus belonging to Chrysiogenetes, while strain S7 belongs to the Deferribacteres, with greater than 98% 16S rRNA gene similarity to Geovibrio ferrireducens. Strain KM is related to Malonomonas rubra, Pelobacter acidigallici, and Desulfuromusa spp., with 96 to 97% 16S rRNA gene similarity. Strain pn1 is 99% similar to Pseudomonas stutzeri. Strains S5, S7, and KM are obligately anaerobic selenate-respiring microorganisms, while strain pn1 is facultatively anaerobic. Besides respiring selenate, all these strains also respire nitrate. 相似文献
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Respiratory syncytial virus (RSV), a member of the Paramyxoviridae family, encodes a small hydrophobic (SH) protein of unknown function. Parainfluenza virus 5 (PIV5), a prototypical paramyxovirus, also encodes an SH protein, which inhibits tumor necrosis factor alpha (TNF-α) signaling. In this study, recombinant PIV5 viruses without their own SH but containing RSV SH (from RSV strain A2 or B1) in its place (PIV5ΔSH-RSV SH) and RSV lacking its own SH (RSVΔSH) were generated and analyzed. The results indicate that the SH protein of RSV has a function similar to that of PIV5 SH and that it can inhibit TNF-α signaling. 相似文献
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Keratinases degrade feather in presence of a suitable reducing agent. Here we have demonstrated that conventional serine and
cysteine proteases (subtilsin, chymotrypsin and papain) which selectively cleave proteins at the hydrophobic P1 residues also
degrade feathers in presence of a suitable reducing agent in the form of live cells or chemical reductants. Further, trypsin
and pepsin were also shown to degrade feather after cleaving hydrophobic residues of feathers following 2 h pre-treatment
by any of the proteases. 相似文献
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