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91.
Hari D Upadhyaya Sangam L Dwivedi Michael Baum Rajeev K Varshney Sripada M Udupa Cholenahalli LL Gowda David Hoisington Sube Singh 《BMC plant biology》2008,8(1):106
Background
Plant genetic resources (PGR) are the basic raw materials for future genetic progress and an insurance against unforeseen threats to agricultural production. An extensive characterization of PGR provides an opportunity to dissect structure, mine allelic variations, and identify diverse accessions for crop improvement. The Generation Challenge Program conceptualized the development of "composite collections" and extraction of "reference sets" from these for more efficient tapping of global crop-related genetic resources. In this study, we report the genetic structure, diversity and allelic richness in a composite collection of chickpea using SSR markers, and formation of a reference set of 300 accessions. 相似文献92.
93.
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95.
Smith EJ Corrigan RM van der Sluis T Gründling A Speziale P Geoghegan JA Foster TJ 《Molecular microbiology》2012,83(4):789-804
The Sbi protein of Staphylococcus aureus comprises two IgG‐binding domains similar to those of protein A and a region that triggers the activation of complement C3. Sbi is expressed on the cell surface but its C‐terminal domain lacks motifs associated with wall or membrane anchoring of proteins in Gram‐positive bacteria. Cell‐associated Sbi fractionates with the cytoplasmic membrane and is not solubilized during protoplast formation. S. aureus expressing Sbi truncates of the C‐terminal Y domain allowed identification of residues that are required for association of Sbi with the membrane. Recombinant Sbi bound to purified cytoplasmic membrane material in vitro and to purified lipoteichoic acid. This explains how Sbi partitions with the membrane in fractionation experiments yet is partially exposed on the cell surface. An LTA‐defective mutant of S. aureus had reduced levels of Sbi in the cytoplasmic membrane. 相似文献
96.
Corrigan DK Schulze H Henihan G Ciani I Giraud G Terry JG Walton AJ Pethig R Ghazal P Crain J Campbell CJ Mount AR Bachmann TT 《Biosensors & bioelectronics》2012,34(1):178-184
Using electrochemical impedance spectroscopy (EIS) the sensitive and specific detection of the antibiotic resistance gene mecA has been demonstrated. The gene sequence was obtained from clinical Staphylococcus aureus isolates. Initially a mecA specific probe was selected from hybridisation tests with a 3' and 5' version of a previously published probe sequence. When immobilised on a gold electrode in PNA form it was possible to detect hybridisation of mecA PCR product electrochemically at concentrations as low as 10nM. By incorporating an undecane-thiol and 1.8 nm glycol spacer into the PNA probe it was possible to extend the limit of detection for mecA to 10 pM. Most published studies on EIS and nucleic acid detection report the use of short artificial DNA sequences or novel signal amplification schemes which improve sensitivity whereas this study reports the successful detection of long DNA fragments produced by PCR following extraction from clinical isolates. Finally, using screen printed electrodes the paper demonstrates hybridisation monitoring of mecA in an "on-line" assay format under ambient conditions which paves the way for rapid mecA detection in point of care scenarios. 相似文献
97.
The objective of this work was to apply artificial neural networks (ANNs) to examine the relative importance of various factors,
both formulation and process, governing the in-vitro dissolution from enteric-coated sustained release (SR) minitablets. Input
feature selection (IFS) algorithms were used in order to give an estimate of the relative importance of the various formulation
and processing variables in determining minitablet dissolution rate. Both forward and backward stepwise algorithms were used
as well as genetic algorithms. Networks were subsequently trained using the back propagation algorithm in order to check whether
or not the IFS process had correctly located any unimportant inputs. IFS gave consistent rankings for the importance of the
various formulation and processing variables in determining the release of drug from minitablets. Consistent ranking was achieved
for both indices of the release process; ie, the time taken for release to commence through the enteric coat (Tlag) and that for the drug to diffuse through the SR matrix of the minitablet into the dissolution medium (T90-10). In the case of the Tlag phase, the main coating parameters, along with the original batch blend size and the blend time with lubricant, were found
to have most influence. By contrast, with the T90-10 phase, the amounts of matrix forming polymer and direct compression filler were most important. In the subsequent training
of the ANNs, removal of inputs regarded as less important led to improved network performance. ANNs were capable of ranking
the relative importance of the various formulations and processing variables that influenced the release rate of the drug
from minitablets. This could be done for all main stages of the release process. Subsequent training of the ANN verified that
removal of less relevant inputs from the training process led to an improved performance from the ANN. 相似文献
98.
J. E. Corrigan J. H. Lashomb M. L. May C. Schal 《Entomologia Experimentalis et Applicata》1991,61(2):139-147
Female Edovum puttleri Grissell [Hymenoptera: Eulophidae], reared from eggs of Leptinotarsa decemlineata (Say) or Leptinotarsa texana Schaeffer [Coleoptera: Chrysomelidae], were videotaped as they attacked egg masses of L. decemlineata containing 20 host eggs. We identified 15 components of ovipositional behavior. Parasitoids reared on L. texana attacked and oviposited in significantly more host eggs than did females reared on L. decemlineata. Ethometric analyses of behavioral transitions and a clustering analysis of 34 behavioral parameters showed that females reared on L. texana attacked the host egg mass in a different manner than those reared from L. decemlineata. It was concluded that differences were associated with the host species upon which they were reared. Contrary to previous reports, mortality of unparasitized hosts was caused by an ovipositor probe of short duration, which was not related to host-feeding. 相似文献
99.
Conway LL. Powell 《Plant and Soil》1981,62(2):231-239
Summary White clover and onion plants were grown from seed in pots of sandy loam above pads of mycorrhizal inoculum soil at 0.17–1.40
g/pot (equivalent to 250–2000 kg/ha) and harvested on four occasions. In sterilized soil increasing inoculum rates increased
the onset and size of the mycorrhizal growth response of white clover. In unsterilized soil the indigenous mycorrhizal fungi
greatly stimulated growth of both clover and onion. Nevertheless, all mycorrhizal inoculum rates further stimulated shoot
growth in onion (92% increase over all harvests), while only the highest inoculum rate significantly stimulated clover growth
(52% increase). 相似文献
100.