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N.A.T. Carvalho J.G. Soares D.C. Souza F.S. Vannucci R. Amaral J.R.G. Maio J.N.S. Sales M.F. Sá Filho P.S. Baruselli 《Theriogenology》2014
Three experiments were designed to evaluate the effect of different circulating progesterone (P4) concentrations during synchronization of ovulation protocol for timed artificial insemination of seasonal anestrous buffalo cows. In the first trial, ovariectomized cows were randomly allocated into one of three groups: using new P4 devices (G-New; n = 8), using devices previously used for 9 days (G-Used1x; n = 8), and using devices previously used for 18 days (G-Used2x; n = 8). The P4 device was maintained for 9 days, and the circulating P4 concentration was measured daily. The circulating P4 concentrations during the P4 device treatment were the lowest for G-Used2x (1.10 ± 0.04 ng/mL), intermediate for G-Used1x (1.52 ± 0.05 ng/mL), and the highest for G-New (2.47 ± 0.07 ng/mL; P = 0.001). In the second trial, 31 anestrous cows had their ovarian follicular dynamics evaluated after receiving the treatments described previously (G-New [n = 10], G-Used1x [n = 11], and G-Used2x [n = 10]). At insertion of the P4 device, cows were administered 2.0 mg of estradiol benzoate. Nine days later, the P4 device was removed and cows were administered 0.53 mg of cloprostenol sodium plus 400 IU of eCG. Forty-eight hours after P4 device removal, 10 μg of buserelin acetate was administered. There were no differences among the groups (G-New vs. G-Used1x vs. G-Used2x) in diameter of the largest follicle at P4 device removal (9.0 ± 0.8 vs. 10.1 ± 0.9 vs. 8.6 ± 0.8 mm; P = 0.35), in interval from P4 device removal to ovulation (77.1 ± 4.5 vs. 76.5 ± 4.7 vs. 74.0 ± 4.4 hours; P = 0.31), or in ovulation rate (80.0% vs. 81.8% vs. 60.0%; P = 0.51). In experiment 3, 350 anestrous cows were randomly assigned into one of the three treatments described previously (G-New, n = 111; G-Used1x, n = 121; G-Used2x, n = 118) and received a timed artificial insemination for 16 hours after buserelin treatment. The 30-day pregnancy rates did not differ among groups (55.9% vs. 55.4% vs. 48.3%; P = 0.39). Thus, the low circulating P4 concentrations released from a used P4 device efficiently control the ovarian follicular growth and had no detrimental effect on the pregnancy rates of the seasonal anestrous buffalo cows. 相似文献
43.
Hayley M Bennett Hoi Ping Mok Effrossyni Gkrania-Klotsas Isheng J Tsai Eleanor J Stanley Nagui M Antoun Avril Coghlan Bhavana Harsha Alessandra Traini Diogo M Ribeiro Sascha Steinbiss Sebastian B Lucas Kieren SJ Allinson Stephen J Price Thomas S Santarius Andrew J Carmichael Peter L Chiodini Nancy Holroyd Andrew F Dean Matthew Berriman 《Genome biology》2014,15(11)
44.
Grouping the 20 residues is a classic strategy to discover ordered patterns and insights about the fundamental nature of proteins, their structure, and how they fold. Usually, this categorization is based on the biophysical and/or structural properties of a residue's side-chain group. We extend this approach to understand the effects of side chains on backbone conformation and to perform a knowledge-based classification of amino acids by comparing their backbone phi, psi distributions in different types of secondary structure. At this finer, more specific resolution, torsion angle data are often sparse and discontinuous (especially for nonhelical classes) even though a comprehensive set of protein structures is used. To ensure the precision of Ramachandran plot comparisons, we applied a rigorous Bayesian density estimation method that produces continuous estimates of the backbone phi, psi distributions. Based on this statistical modeling, a robust hierarchical clustering was performed using a divergence score to measure the similarity between plots. There were seven general groups based on the clusters from the complete Ramachandran data: nonpolar/beta-branched (Ile and Val), AsX (Asn and Asp), long (Met, Gln, Arg, Glu, Lys, and Leu), aromatic (Phe, Tyr, His, and Cys), small (Ala and Ser), bulky (Thr and Trp), and, lastly, the singletons of Gly and Pro. At the level of secondary structure (helix, sheet, turn, and coil), these groups remain somewhat consistent, although there are a few significant variations. Besides the expected uniqueness of the Gly and Pro distributions, the nonpolar/beta-branched and AsX clusters were very consistent across all types of secondary structure. Effectively, this consistency across the secondary structure classes implies that side-chain steric effects strongly influence a residue's backbone torsion angle conformation. These results help to explain the plasticity of amino acid substitutions on protein structure and should help in protein design and structure evaluation. 相似文献
45.
Chien-Hsing Lin Ling-Hui Li Sheng-Feng Ho Tzu-Po Chuang Jer-Yuarn Wu Yuan-Tsong Chen Cathy SJ Fann 《BMC genetics》2008,9(1):1-9
Background
Winter migration of immature brown trout (Salmo trutta) into freshwater rivers has been hypothesized to result from physiologically stressful combinations of high salinity and low temperature in the sea.Results
We sampled brown trout from two Danish populations entering different saline conditions and quantified expression of the hsp70 and Na/K-ATPases α 1b genes following acclimation to freshwater and full-strength seawater at 2°C and 10°C. An interaction effect of low temperature and high salinity on expression of both hsp70 and Na/K-ATPase α 1b was found in trout from the river entering high saline conditions, while a temperature independent up-regulation of both genes in full-strength seawater was found for trout entering marine conditions with lower salinities.Conclusion
Overall our results support the hypothesis that physiologically stressful conditions in the sea drive sea-run brown trout into freshwater rivers in winter. However, our results also demonstrate intra-specific differences in expression of important stress and osmoregulative genes most likely reflecting adaptive differences between trout populations on a regional scale, thus strongly suggesting local adaptations driven by the local marine environment. 相似文献46.
In recent years there has been an increased interest in using protein mass spectroscopy to discriminate diseased from healthy individuals with the aim of discovering molecular markers for disease. A crucial step before any statistical analysis is the pre-processing of the mass spectrometry data. Statistical results are typically strongly affected by the specific pre-processing techniques used. One important pre-processing step is the removal of chemical and instrumental noise from the mass spectra. Wavelet denoising techniques are a standard method for denoising. Existing techniques, however, do not accommodate errors that vary across the mass spectrum, but instead assume a homogeneous error structure. In this paper we propose a novel wavelet denoising approach that deals with heterogeneous errors by incorporating a variance change point detection method in the thresholding procedure. We study our method on real and simulated mass spectrometry data and show that it improves on performances of peak detection methods. 相似文献
47.
Vanek O Nálezková M Kavan D Borovicková I Pompach P Novák P Kumar V Vannucci L Hudecek J Hofbauerová K Kopecký V Brynda J Kolenko P Dohnálek J Kaderávek P Chmelík J Gorcík L Zídek L Sklenár V Bezouska K 《The FEBS journal》2008,275(22):5589-5606
We investigated the soluble forms of the earliest activation antigen of human leukocyte CD69. This receptor is expressed at the cell surface as a type II homodimeric membrane protein. However, the elements necessary to prepare the soluble recombinant CD69 suitable for structural studies are a matter of controversy. We describe the physical, biochemical and in vivo characteristics of a highly stable soluble form of CD69 obtained by bacterial expression of an appropriate extracellular segment of this protein. Our construct has been derived from one used for CD69 crystallization by further optimization with regard to protein stability, solubility and easy crystallization under conditions promoting ligand binding. The resulting protein is stable at acidic pH and at temperatures of up to 65 degrees C, as revealed by long-term stability tests and thermal denaturation experiments. Protein NMR and crystallography confirmed the expected protein fold, and revealed additional details of the protein characteristics in solution. The soluble CD69 refolded in a form of noncovalent dimers, as revealed by gel filtration, sedimentation velocity measurements, NMR and dynamic light scattering. The soluble CD69 proved to be remarkably stable in vivo when injected into the bloodstream of experimental mice. More than 70% of the most stable CD69 proteins is preserved intact in the blood 24 h after injection, whereas the less stable CD69 variants are rapidly taken up by the liver. 相似文献
48.
49.
Monika Holubova Martin Leba Markéta Sedmikova Luca Vannucci Vratislav Horak 《In vitro cellular & developmental biology. Animal》2012,48(10):610-618
Establishment of new animal models using selected cell lines with different behaviour is very important for cancer investigations. In this study, we describe three morphologically distinct rat sarcoma clones??C4, C7 and D6??isolated from the R5-28 cell line. Cells of all clones expressed vimentin, fibronectin, laminin, collagen IV and matrix metalloproteinases 2 and 9. However, desmin, cytokeratins 8 and 18, ZO-1 and desmoplakins I and II were not detected. Significant proliferative capacity was documented by proliferating cell nuclear antigen expression and BrdU positivity. Karyotype of the C4, C7 and D6 cells greatly differed from diploid chromosome number of normal rat somatic cells. High expression of three cytokines??monocyte chemoattractant protein 1, tissue inhibitor of metalloproteinases 1 and vascular endothelial growth factor??was observed in all three clones. However, they varied in concentration of chemokines associated with neutrophil migration and activation??cytokine induced neutrophil chemoattractant 2 and lipopolysaccharide induced CXC chemokine. The C4 clone showed spontaneous tumour regression in vivo that was associated with significant changes in lymphocyte subpopulations. 相似文献
50.
Ying-Chao Lin Ai-Ru Hsieh Ching-Lin Hsiao Shang-Jung Wu Hui-Min Wang Ie-Bin Lian Cathy SJ Fann 《Journal of biomedical science》2014,21(1)