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11.
Aqueous Solution‐Processable Small Molecular Metal‐Chelate Complex Electrolyte for Flexible All‐Solid State Energy Storage Devices 下载免费PDF全文
A small molecular metal‐chelate complex, tris(8‐hydroxyquinoline‐5‐sulfonic acid) aluminum (AlQSA3), that has three sulfonic acid groups per molecule leading to an excellent solubility in water is reported as a liquid‐free perfect solid‐state electrolyte for flexible film‐type all‐solid‐state energy storage devices. The AlQSA3 material is synthesized by one‐step reaction of aluminum triisopropoxide and 8‐hydroxyquinoline‐5‐sulfonic acid. The aqueous solutions of AlQSA3 are applied to fabricate flexible film‐type all‐solid state electric double layer capacitors with indium‐tin oxide thin film electrodes. The ion conductivity of the AlQSA3 film reaches 0.116 mS cm?1, while a pronounced hysteresis are obtained in the cyclic voltammetry measurement. The AlQSA3 film capacitors exhibit an output voltage of 1.5 V at 20 μA cm?2, which is considerably stable by the repeated operation. In particular, the peak output voltage is well kept even after 180° bending for 500 times in the case of the flexible AlQSA3 film capacitors. 相似文献
12.
H. Llaneza Coalla J.M. Blanco FernándezM.A. Morís Morán M.R. López Bobo 《Bioresource technology》2009,100(17):3843-3847
In view of the pressing problem that appears in our region (Asturias, north of Spain) with the residues from the cider production, it was decided to test this kind of material as a co-substrate joint with slaughterhouse waste in a laboratory unit. 相似文献
13.
Natural sway frequencies and damping ratios of trees: concepts,review and synthesis of previous studies 总被引:3,自引:0,他引:3
Previous studies that measured the natural frequencies and damping ratios of conifer trees were reviewed and results synthesized. Analysis of natural frequency measurements from 602 trees, belonging to eight different species, showed that natural frequency was strongly and linearly related to the ratio of diameter at breast height to total tree height squared (i.e., DBH/H
2). After accounting for their size, pines (Pinus spp.) were found to have a significantly lower natural frequency than both spruce (Picea spp.) and Douglas-fir (Pseudotsuga spp.). Natural sway frequencies of de-branched trees were significantly higher than those of the same trees with the branches intact, and the difference increased with an increasing ratio of DBH/H
2. Damping mechanisms were discussed and methods for measuring damping ratio were presented. Analysis of available data suggested that internal damping ratios were typically less than 0.05 and were not related to tree diameter. External damping was mainly due to aerodynamic drag on the foliage and contact between the crowns of adjacent trees. Analysis of data from previous wind-tunnel studies indicated that damping due to aerodynamic drag is a nonlinear function of velocity. Damping due to crown contact has been suggested by a previous author to be a function of both the distance to and the size of adjacent trees. Therefore, in uniformly spaced stands it may be possible to model crown contact damping as a function of stand density index (SDI), a common forestry measure which incorporates both of these variables. 相似文献
14.
《Bioscience, biotechnology, and biochemistry》2013,77(12):2912-2920
The textures of cooked rice prepared from aged rice grains and their improvement by reducing agents were investigated. For aged rice that was stored for 5 months without air by the operation of a vacuum packing machine, the stickiness/hardness ratio of cooked rice was as low as that of aged rice stored in air. The results of electrophoresis showed that oxidation of proteins in the former was advanced to the same degree as in the latter. The stickiness/hardness ratios of the aged rice were increased by the addition of sodium sulfite, cysteine, and dithiothreitol to the cooking water. Sodium sulfite, cysteine, and dithiothreitol cleave disulfide bonds to sulfhydryl groups. Therefore, cleaving disulfide bonds to sulfhydryl groups improved the texture. The addition of them to the cooking water also increased the extractable solids at the time of heating. Hence cleaving disulfide bonds to sulfhydryl groups must increase extractable solids. Consequently, the gelatinized paste layer thickened and the thick paste layer softened the cooked rice. 相似文献
15.
Hangsik?Moon David?F.?HildebrandEmail author 《In vitro cellular & developmental biology. Plant》2003,39(6):623-628
Summary Cermination of soybean [Glycine max (L.) Merrill] somatic embryos and conversion to whole plants are generally low. This study was conducted to investigate the
effects of proliferation, maturation, and desiccation methods on conversion of soybean somatic embryos to plants. Soybean
cv. Jack somatic embryos, proliferated on a solid medium containing 90.5 μM (20 mgl−1) 2.4-dichlorophenoxyacetic acid (2.4-D) (MSD20), showed a regeneration rate signficantly higher than those proliferated in
a liquid medium containing 45.25 μM (10mgl−1) 2,4-D (FN Lite). When a liquid medium without 2,4-D and B5 vitamins (FN Superlite) was used for maturation, the duration
of time necessary for embryo development could be shortened by more than a month compared to maturation on a standard solid
medium (MSM6AC). An air-drying method, in which somatic embryos were desiccated in an empty sealed Petri dish for 3–5d, gave
rise to the best germination efficiency among the four desiccation methods tested: fast, slow, air, and KCl methods. The final
percentage of moisture seems important since embyros over-dried by the fast and slow methods did not convert well into plants. 相似文献
16.
John D. Finan Holly A. Leddy Farshid Guilak 《Biochemical and biophysical research communications》2011,(2):431
Osmotic stress is a potent regulator of biological function in many cell types, but its mechanism of action is only partially understood. In this study, we examined whether changes in extracellular osmolality can alter chromatin condensation and the rate of nucleocytoplasmic transport, as potential mechanisms by which osmotic stress can act. Transport of 10 kDa dextran was measured both within and between the nucleus and the cytoplasm using two different photobleaching methods. A mathematical model was developed to describe fluorescence recovery via nucleocytoplasmic transport. As osmolality increased, the diffusion coefficient of dextran decreased in the cytoplasm, but not the nucleus. Hyper-osmotic stress decreased nuclear size and increased nuclear lacunarity, indicating that while the nucleus was getting smaller, the pores and channels interdigitating the chromatin had expanded. The rate of nucleocytoplasmic transport was increased under hyper-osmotic stress but was insensitive to hypo-osmotic stress, consistent with the nonlinear osmotic properties of the nucleus. The mechanism of this osmotic sensitivity appears to be a change in the size and geometry of the nucleus, resulting in a shorter effective diffusion distance for the nucleus. These results may explain physical mechanisms by which osmotic stress can influence intracellular signaling pathways that rely on nucleocytoplasmic transport. 相似文献
17.
Detection of native-like models for amino acid sequences of unknown three-dimensional structure in a data base of known protein conformations. 总被引:13,自引:0,他引:13
We present an approach which can be used to identify native-like folds in a data base of protein conformations in the absence of any sequence homology to proteins in the data base. The method is based on a knowledge-based force field derived from a set of known protein conformations. A given sequence is mounted on all conformations in the data base and the associated energies are calculated. Using several conformations and sequences from the globin family we show that the native conformation is identified correctly. In fact the resolution of the force field is high enough to discriminate between a native fold and several closely related conformations. We then apply the procedure to several globins of known sequence but unknown three dimensional structure. The homology of these sequences to globins of known structures in the data base ranges from 49 to 17%. With one exception we find that for all globin sequences one of the known globin folds is identified as the most favorable conformation. These results are obtained using a force field derived from a data base devoid of globins of known structure. We briefly discuss useful applications in protein structural research and future development of our approach. 相似文献
18.
A pair of stereoisomeric covalent adducts to guanine in double-stranded DNA, derived from the reaction of mutagenic and tumorigenic metabolites of benzo[a]pyrene, have been well characterized structurally and thermodynamically. Both high-resolution NMR solution structures and an array of thermodynamic data are available for these 10S (+)- and 10R (-)-trans-anti -[BP]-N(2)-dG adducts in double-stranded deoxyoligonucleotides. The availability of experimentally well-characterized duplexes containing these two stereoisomeric guanine adducts provides an opportunity for evaluating the molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) method for computing thermodynamic properties from molecular dynamics ensembles. We have carried out 3-ns molecular dynamics simulations, using NMR solution structures as the starting models for the 10S (+)- and 10R (-)-trans-anti-dG adducts in a DNA duplex 11-mer using AMBER 6.0. We employed the MM-PBSA method to compute the free energies, enthalpies, and entropies of the two adducts. Our complete thermodynamic analysis agrees quite well with the full experimental thermodynamic characterization of these adducts, showing essentially equal stabilities of the two adducts. We also calculated the nuclear Overhauser effect (NOE) distances from the molecular dynamics trajectories, and compared them against the experimental NMR-derived NOE distances. Our results showed that the simulated structures are in good agreement with the NMR experimental NOE data. Furthermore, the molecular dynamics simulations provided new structural and biological insights. Specifically, the puzzling observation that the BP aromatic ring system in the 10S (+)-trans-anti-dG adduct is more exposed to the aqueous solvent than the 10R (-)-trans-anti-dG adduct, is rationalized in terms of the adduct structures. The structural and thermodynamic features of these stereoisomeric adducts are also discussed in relation to their reported low susceptibilities to nucleotide excision repair. 相似文献
19.
20.
The large conducting arteries in vertebrates are composed of a specialized extracellular matrix designed to provide pulse dampening and reduce the work performed by the heart. The mix of matrix proteins determines the passive mechanical properties of the arterial wall1. When the matrix proteins are altered in development, aging, disease or injury, the arterial wall remodels, changing the mechanical properties and leading to subsequent cardiac adaptation2. In normal development, the remodeling leads to a functional cardiac and cardiovascular system optimized for the needs of the adult organism. In disease, the remodeling often leads to a negative feedback cycle that can cause cardiac failure and death. By quantifying passive arterial mechanical properties in development and disease, we can begin to understand the normal remodeling process to recreate it in tissue engineering and the pathological remodeling process to test disease treatments.Mice are useful models for studying passive arterial mechanics in development and disease. They have a relatively short lifespan (mature adults by 3 months and aged adults by 2 years), so developmental3 and aging studies4 can be carried out over a limited time course. The advances in mouse genetics provide numerous genotypes and phenotypes to study changes in arterial mechanics with disease progression5 and disease treatment6. Mice can also be manipulated experimentally to study the effects of changes in hemodynamic parameters on the arterial remodeling process7. One drawback of the mouse model, especially for examining young ages, is the size of the arteries. We describe a method for passive mechanical testing of carotid arteries from mice aged 3 days to adult (approximately 90 days). We adapt a commercial myograph system to mount the arteries and perform multiple pressure or axial stretch protocols on each specimen. We discuss suitable protocols for each age, the necessary measurements and provide example data. We also include data analysis strategies for rigorous mechanical characterization of the arteries. 相似文献