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81.
Dolińska B Caban A Leszczyńska L Oczkowicz G Ryszka F 《Protein and peptide letters》2011,18(6):540-544
The prolactin (PRL) permeation through the pericardium depending on the species of origin (porcine, bovine and ovine) was studied, and the parameters of its bioavailability were calculated. An in vitro model using pericardium as a natural membrane and Frantz cell method was applied. Significant differences in permeation were observed depending on the species of origin. Within 5 h, 17.5% of bovine PRL, 27.2% of porcine PRL and 90.3% of ovine PRL permeated the pericardium. The amount of permeated ovine PRL was 3.3-fold higher than porcine PRL and 5.2-fold higher than bovine PRL. The maximum concentration of permeated PRL was reached in the thirtieth minute of the experiment and was the highest for ovine PRL (C(max) = 677.21 μg/cm2) and the lowest for bovine PRL (C(max) = 259.97 μg/cm2). Bioavailability of PRL through the pericardium is 3.3-fold greater for ovine PRL in comparison to porcine or bovine PRL. The relative extent of bioavailability for bovine and ovine prolactin versus the porcine PRL standard was 85.6% and 229.3%, respectively. 相似文献
82.
Daniel F. Carlson Aron M. Geurts John R. Garbe Chang-Won Park Artur Rangel-Filho Scott M. O’Grady Howard J. Jacob Clifford J. Steer David A. Largaespada Scott C. Fahrenkrug 《Transgenic research》2011,20(1):29-45
Heightened interest in relevant models for human disease increases the need for improved methods for germline transgenesis.
We describe a significant improvement in the creation of transgenic laboratory mice and rats by chemical modification of Sleeping Beauty transposons. Germline transgenesis in mice and rats was significantly enhanced by in vitro cytosine-phosphodiester-guanine
methylation of transposons prior to injection. Heritability of transgene alleles was also greater from founder mice generated
with methylated versus non-methylated transposon. The artificial methylation was reprogrammed in the early embryo, leading
to founders that express the transgenes. We also noted differences in transgene insertion number and structure (single-insert
versus concatemer) based on the influence of methylation and plasmid conformation (linear versus supercoiled), with supercoiled
substrate resulting in efficient transpositional transgenesis (TnT) with near elimination of concatemer insertion. Combined,
these substrate modifications resulted in increases in both the frequency of transgenic founders and the number of transgenes
per founder, significantly elevating the number of potential transgenic lines. Given its simplicity, versatility and high
efficiency, TnT with enhanced Sleeping Beauty components represents a compelling non-viral approach to modifying the mammalian germline. 相似文献
83.
84.
Using domestic pigs as an animal model, we here validated a reproducible and standardized myocardial infarction (MI) surgical model, to achieve the largest possible infarct extent with the lowest morbidity and mortality. To this end, we included several anesthetic and perisurgical precautions to minimize surgical complications. Mortality and morbidity rates were compared among groups of pigs that underwent permanent occlusion at different locations of either the left circumflex or left anterior descending artery. In addition, to compare the resulting MI between groups, data were collected by using cardiac biomarkers (including troponin I), electrocardiography, and echocardiography. These data were correlated to the final mean infarct size calculated by microscopic studies. Proximal occlusions lead to high mortality rates, whereas distal occlusions induced rather small MI areas. The optimal occlusion site in terms of morbidity, mortality, and lesion extent was the midpoint of the left anterior descending artery. In this group, only one pig died, and group cardiac data showed a rise in biomarker levels, marked left ventricular dysfunction on electrocardiography and echocardiography, and well-defined transmural MI in both ventricles. Infarct size quantitated through histologic studies revealed an average 15% ventricular lesion. Because interanimal variability in results from this group was negligible, we consider that the induced myocardial injury of this model is reliable. 相似文献
85.
Mitoraj MP Parafiniuk M Srebro M Handzlik M Buczek A Michalak A 《Journal of molecular modeling》2011,17(9):2337-2352
The present study characterizes changes in the electronic structure of reactants during chemical reactions based on the combined
charge and energy decomposition scheme, ETS-NOCV (extended transition state–natural orbitals for chemical valence). Decomposition
of the activation barrier, ΔE
#, into stabilizing (orbital interaction, ΔE
orb, and electrostatic, ΔE
elstat) and destabilizing (Pauli repulsion, ΔE
Pauli, and geometry distortion energy, ΔE
dist) factors is discussed in detail for the following reactions: (I) hydrogen cyanide to hydrogen isocyanide, HCN → CNH isomerization; (II) Diels-Alder cycloaddition of ethene to 1,3-butadiene; and two catalytic processes, i.e., (III) insertion of ethylene into the metal-alkyl bond using half-titanocene with phenyl-phenoxy ligand catalyst; and (IV) B–H bond activation catalyzed by an Ir-containing catalyst. Various reference states for fragments were applied in ETS-NOCV
analysis. We found that NOCV-based deformation densities (Δρ
i) and the corresponding energies ΔE
orb(i) obtained from the ETS-NOCV scheme provide a very useful picture, both qualitatively and quantitatively, of electronic
density reorganization along the considered reaction pathways. Decomposition of the barrier ΔE# into stabilizing and destabilizing contributions allowed us to conclude that the main factor responsible for the existence
of positive values of ΔE
# for all processes (I, II, III and IV) is Pauli interaction, which is the origin of steric repulsion. In addition, in the case of reactions II, III and IV, a significant degree of structural deformation of the reactants, as measured by the geometry distortion energy, plays an
important role. Depending on the reaction type, stabilization of the transition state (relatively to the reactants) originating
either from the orbital interaction term or from electrostatic attraction can be of vital importance. Finally, use of the
ETS-NOCV method to describe catalytic reactions allows extraction of information on the role of catalysts in determination
of ΔE
#. 相似文献
86.
Bilayer lipid membranes composed of phosphatidylcholine and decanoic acid or phosphatidylcholine and decylamine were investigated
using electrochemical impedance spectroscopy. Interaction between membrane components causes significant deviations from the
additivity rule. Area, capacitance, and stability constant values for the complexes were calculated based on the model assuming
1:1 stoichiometry, and the model was validated by comparison of these values to experimental results. We established that
phosphatidylcholine and decylamine form highly stable 1:1 complexes. In the case of decanoic acid-modified phosphatidylcholine
membranes, complexes with stoichiometries other than 1:1 should be taken into consideration. 相似文献
87.
Resende Lde S Pedretti Gomes KC Andriolo A Genaro G Remy GL Almeida Ramos Vd 《Journal of applied animal welfare science : JAAWS》2011,14(3):247-254
Nonhuman animals in captivity can experience environmental privation that results in their exhibiting abnormal behaviors. Environmental enrichment techniques can help improve their welfare. This study investigated the behavior of 8 zoo-housed oncilla cats (Leopardus tigrinus) in response to 2 odors (catnip and cinnamon) introduced individually into the animals' enclosures for 3 consecutive days. Proportion of scans spent engaging in stereotypical pacing were compared before, during, and after treatments. The addition of cinnamon reduced the proportion of pacing during and after enrichment (Wilcoxon: Z = 3.16, p < .001; Z = 3.16, p < .001, respectively), indicating a prolonged effect of the enrichment on the animals' behavior. Catnip appears to have elicited no significant difference in the stereotypic pacing before, during, or after the enrichment (Friedman: X(2) = 2.69; p = .260). The results highlight the potential use of cinnamon as a method of environmental enrichment for small captive-housed cats. 相似文献
88.
Characterization of all chromosomes of the Andean G19833 bean genotype was carried out by fluorescent in situ hybridization. Eleven single-copy genomic sequences, one for each chromosome, two BACs containing subtelomeric and pericentromeric repeats and the 5S and 45S ribosomal DNA (rDNA) were used as probes. Comparison to the Mesoamerican accession BAT93 showed little divergence, except for additional 45S rDNA sites in four chromosome pairs. Altogether, the results indicated a relative karyotypic stability during the evolution of the Andean and Mesoamerican gene pools of P. vulgaris. 相似文献
89.
Ruiz JC D'Afonseca V Silva A Ali A Pinto AC Santos AR Rocha AA Lopes DO Dorella FA Pacheco LG Costa MP Turk MZ Seyffert N Moraes PM Soares SC Almeida SS Castro TL Abreu VA Trost E Baumbach J Tauch A Schneider MP McCulloch J Cerdeira LT Ramos RT Zerlotini A Dominitini A Resende DM Coser EM Oliveira LM Pedrosa AL Vieira CU Guimarães CT Bartholomeu DC Oliveira DM Santos FR Rabelo ÉM Lobo FP Franco GR Costa AF Castro IM Dias SR Ferro JA Ortega JM Paiva LV Goulart LR Almeida JF Ferro MI Carneiro NP 《PloS one》2011,6(4):e18551
Background
Corynebacterium pseudotuberculosis, a Gram-positive, facultative intracellular pathogen, is the etiologic agent of the disease known as caseous lymphadenitis (CL). CL mainly affects small ruminants, such as goats and sheep; it also causes infections in humans, though rarely. This species is distributed worldwide, but it has the most serious economic impact in Oceania, Africa and South America. Although C. pseudotuberculosis causes major health and productivity problems for livestock, little is known about the molecular basis of its pathogenicity.Methodology and Findings
We characterized two C. pseudotuberculosis genomes (Cp1002, isolated from goats; and CpC231, isolated from sheep). Analysis of the predicted genomes showed high similarity in genomic architecture, gene content and genetic order. When C. pseudotuberculosis was compared with other Corynebacterium species, it became evident that this pathogenic species has lost numerous genes, resulting in one of the smallest genomes in the genus. Other differences that could be part of the adaptation to pathogenicity include a lower GC content, of about 52%, and a reduced gene repertoire. The C. pseudotuberculosis genome also includes seven putative pathogenicity islands, which contain several classical virulence factors, including genes for fimbrial subunits, adhesion factors, iron uptake and secreted toxins. Additionally, all of the virulence factors in the islands have characteristics that indicate horizontal transfer.Conclusions
These particular genome characteristics of C. pseudotuberculosis, as well as its acquired virulence factors in pathogenicity islands, provide evidence of its lifestyle and of the pathogenicity pathways used by this pathogen in the infection process. All genomes cited in this study are available in the NCBI Genbank database (http://www.ncbi.nlm.nih.gov/genbank/) under accession numbers and CP001809. CP001829相似文献90.