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731.
Inmaculada Fernández 《Grana》2013,52(4-5):308-310
The type and position of the particular apertural system in Thesium divaricatum has been discussed. The study of the exine stratification shows a discontinous endexine that can be explained by the harmomegathic efficiency hypothesis to accomodate volume changes, caused by climatic variation. 相似文献
732.
Inmaculada Sampedro Mariangela Giubilei Tomas Cajthaml Ermanno Federici Federico Federici Maurizio Petruccioli Alessandro Dannibale 《Bioresource technology》2009,100(23):6098-6106
The short-term response of the resident soil bacterial and fungal communities to the addition of 5% (w/w) of either dry olive mill residue (DOR), DOR treated with Phlebia sp. (PTDOR) or DOR previously extracted with water (WEDOR) was investigated. As opposed to bacteria, the diversity of fungi increased upon the amendments as assessed by denaturing gradient gel electrophoresis of 18S rDNA. Over the first 30 days, phospholipid fatty acids analyses indicated a gradual decrease in the relative abundances of Gram+ bacteria (from 44.8% to 37.9%) and a concomitant increase of Gram− bacteria (from 37.3% to 51.2%) in DOR-amended soil. A considerable increase in the fungal/bacterial ratio was observed after 7 days in DOR, WEDOR and PTDOR-amended soils with respect to the control (0.316, 0.165 and 0.265, respectively, vs. 0.011). The overall microbial activity was stimulated by the amendments as indicated by the higher activity levels of both dehydrogenase and fluorescein diacetate hydrolase. These results indicate that DOR at the application level examined is not toxic on soil microorganisms. 相似文献
733.
734.
J. H. Brock Inmaculada Esparza R. A. Oliver R. L. Spooner 《Biochemical genetics》1980,18(9-10):851-860
Iron-saturated bovine transferrins A, D1, D2, and E were cleaved by trypsin yielding monoferric fragments. The N-terminal fragments (F) of transferrins A and D2 had identical mobility in cellulose acetate electrophoresis, that of transferrin D1 a slower mobility, and that of E a still slower mobility. The C-terminal fragments (S) gave multiple bands which were essentially identical in the case of transferrins A, D1, and E, but of slower mobility in the case of transferrin D2. All four variants had identical N-terminal amino acid sequences. The electrophoretic mobility of the C-terminal fragments was reduced by neuraminidase treatment, but the N-terminal fragments were unaffected. The four transferrin variants therefore appear to be made up from three electrophoretically distinguishable N-terminal halves and two C-terminal halves. The feature responsible for the electrophoretic double banding of homozygous bovine asialotransferrins is consistently associated with the C-terminal half of the molecule. 相似文献
735.
Milagrosa Santos Inmaculada Vallejo Laureana Rebordinos Santiago Gutiérrez Isidro G. Collado Jesús M. Cantoral 《FEMS microbiology letters》1996,137(2-3):153-158
Abstract A transformation system has been developed for the pathogen fungus Botrytis cinerea , based on the utilization of the wide host plasmid pUT737 that contains the Sh ble gene, conferring resistance to phleomycin. Transformed protoplasts were regenerated at 10–25 μg ml−1 of phleomycin, at a frequency of 25–40 transformants per μg of DNA, and they were resistant up to 50 μg ml−1 . Southern hybridization using undigested and digested total DNA showed the presence of circular autonomously replicating plasmid pUT737 in the transformants. Reisolated plasmid from transformed fungus transformed E. coli and rescued plasmid was identified as pUT737. Transformants were grown for four generations under non-selective conditions and replicative plasmids were still detected. Plasmids present in all transformants at this stage had been modified from native pUT737 and showed the same size and configuration indicating that selection through stabilizing plasmid forms has happened. 相似文献
736.
The relationship between small amplitude oscillatory rheological properties and microstructure of plant cell suspensions was
studied. Carrot, broccoli and tomato were selected as model plant systems to generate particles with different microstructures:
clusters of cells with smooth or rough edges and single cells. By analysing the compressive stress undergone by the plant
cells under centrifugation, and comparing this to oscillatory rheometry, agreement was found between the compressive stress
required to compress the dispersions to higher insoluble solids dry mass fractions, and the elastic shear modulus of the plant
dispersions. This indicated that centrifugation is acting as a crude rheological measurement on the samples, rather than measuring
any well-defined “particle phase volume”. We estimated the theoretical critical dry mass fraction above which smooth, roughly
spherical, elastically interacting particles would acquire a non-zero G′, and compared this with the experimental values.
Our results give evidence that for the three vegetable suspensions considered here, the elastic rheology observed is not coming
simply from the packing of smooth particles, but is dominated in the dilute limit by attractive forces or interaction of asperities,
and in the concentrated limit by deformation and buckling acting together. Improved understanding of the particles and their
packing would help in the structuring of food products without adding other texturising or stabilising agents. 相似文献
737.
This is a study of the properties of a zygotic algebra of two linked autosomal loci with different recombination rates in
males and females, without selection or mutation and with random mating. The above-mentioned zygotic algebra contains a genetic
subalgebra. A canonical basis of this subalgebra is constructed and the train roots are calculated. 相似文献
738.
The yielding and flow behaviour of plant suspensions are perhaps the most important rheological properties in process and
product design for applications in paper, biofuel and food industries. Studies are reported here on the yield properties and
flow behaviour of suspensions of plant particles with different shapes (clusters of cells, individual cells and cell fragments).
Carrot and tomato were selected as model plant systems to prepare suspensions at particle dry mass concentrations ranging
from 0.010 to 0.065. The flow behaviour was characterised by an apparent yield stress and shear thinning. The Herschel-Bulkley
yield stress obtained from up and return flow curves was compared to the yield stress calculated from oscillatory measurements.
The dependence of the yield stress values on particle dry mass concentration is approximately a power-law, with a fitted exponent
of 3 ± 0.5 for all the suspensions, independently of the plant origin and particle shape. This same power-law behaviour was
found for the elastic modulus G′, and in this case the exponent was 3 for carrot and 4 for the tomato suspensions. The yield
strain, calculated from oscillatory measurements, decreased slightly with dry mass fraction, but did not follow a power-law.
We discuss possible explanations for power law behaviour, and provide a model for G′ based on folded elastic sheets, which
predicts an exponent of 3, similar to the values obtained for these suspensions. 相似文献