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111.
Eco-efficiency analysis by basf: the method   总被引:2,自引:0,他引:2  
Intention, Goal, Scope, Background  BASF has developed the tool of eco-efficiency analysis to address not only strategic issues, but also issues posed by the marketplace, politics and research. It was a goal to develop a tool for decision-making processes which is useful for a lot of applications in chemistry and other industries. Objectives. The objectives were the development of a common tool, which is usable in a simple way by LCA-experts and understandable by a lot of people without any experience in this field. The results should be shown in such a way that complex studies are understandable in one view. Methods  The method belongs to the rules of ISO 14040 ff. Beyond these life cycle aspect costs, calculations are added and summarized together with the ecological results to establish an eco-efficiency portfolio. Results and Discussion  The results of the studies are shown in a simple way, the eco-efficiency portfolio. Therefore, ecological data are summarized in a special way as described in this paper. It could be shown that the weighting factors, which are used in our method, have a negligible impact on the results. In most cases, the input data have an important impact on the results of the study. Conclusions. It could be shown that the newly developed eco-efficiency analysis is a new tool, which is usable for a lot of problems in decision-making processes. It is a tool which compares different alternatives of a defined customer benefit over the whole life cycle. Recommendations and Outlook  This new method can be a helpful tool in different fields of the evaluation of product or process alternatives. It can be used in research and development as well as in the optimization of customer processes and products. It is an analytical tool for getting more sustainable processes and products in the future  相似文献   
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High-efficiency electrofusion between cells of different sizes was achieved by application of fusing electric pulses to cells in centrifuged pellets. Larger target cells (Chinese hamster ovary or L1210 cells) were stacked among smaller human erythrocytes or erythrocyte ghosts by sequential centrifugation at 700 g to form five-tier pellets in a specially designed centrifugation-electrofusion chamber. The membranes of erythrocytes and ghost were labeled with fluorescent membrane dye (1,1' dioctadecyl-3,3,3'3'-tetramethylindocarbocyanine (Dil)), and the contents of ghosts were loaded with water-soluble fluorescent dye (42-kDa fluorescein isothiocyanate dextran (FITC-dextran)), to monitor heterogeneous cell fusion. Fusion efficiency was assayed by the extent of either membrane dye mixing or contents (FITC-dextran) mixing with target cells. Four rectangular electric pulses at 300 V and 80 microseconds each were found to give the optimal fusion results of approximately 80% heterogeneous fusion by the content-mixing assay and approximately 95% by the membrane-dye-mixing assay. Cell viability remained greater than 80% after electrofusion. Because of the electric breakdown of cell membranes at the beginning of the pulse, the pellet resistance and hence the partial voltage across the pellet reduced rapidly during the remaining pulse time. This voltage redistribution favored the survival of fused cells. The limited colloidal-osmotic swelling of cells in pellets enhanced cell-cell contact and increased the pellet resistance after each pulse. As a result, the partial voltage across the pellet was restored when the next pulse was applied. This redistribution of pulse voltage in the pellet system permitted the breakdown of cell membranes at a lower applied voltage threshold than that required for electrofusion of cells in suspension or in dielectrophoretic cell chains. The cell viability and soluble dye retention within cells (FITC-dextran) remained at the same high levels for 3 h when the cells were incubated in respective culture media with serum at 37 degrees C. Viability and dye retention decreased significantly within 30 min when cells were incubated in phosphate-buffered saline without serum. The pellet technique was applied to form hybridomas by fusion of larger SP2/0 murine myelomas with smaller naive mouse lymphocytes. An optimum of 173 +/- 70 hypoxanthine aminopterin thymidine (HAT)-selected clones of the hybridomas was obtained from 40,000 SP2/0 cells and 1.5 x 10(6) lymphocytes used in each trial. This high-efficiency fusion technique may be adapted to mediate drug and gene transfer to target cells ex vivo as well as to form hybrid cells with limited cell sources.  相似文献   
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Micro Indirect Hemagglutination Test for Cytomegalovirus   总被引:12,自引:4,他引:8  
In an effort to obtain the flexibility and ease of performance of a rapid, serological test for detection of cytomegalovirus antibody, the indirect hemagglutination (IHA) technique was investigated by using a microserological system. Antigens were prepared from tissue cultures of infected human fibroblasts. The specificity of the cytomegalovirus antibody response detected by the IHA test correlated well with the standard neutralization test. The IHA method was more sensitive than the complement fixation test in detecting antibody in congenitally infected newborns. There appeared to be some heterologous antibody response with Herpesvirus hominis or varicella virus infections. The IHA test pattern was found to be very stable with excellent persistence of agglutination.  相似文献   
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Calamagrostis pseudopurpurea is one of only a few endemic species in Germany and is confined to the catchment area of the River Mulde in the states of Saxony and Saxony-Anhalt. We studied the genetic structure and seed viability across its entire distribution area. Patterns of random amplified polymorphic DNA (RAPD) variation were analysed using 183 individuals from 43 stands in order to assess the overall genetic structure and the extent of clonality. In addition, four related Calamagrostis species ( C. canescens , C. epigejos , C. phragmitoides and C. villosa ) were included in our study to consider the probable phylogenetic origin of C. pseudopurpurea . We detected two clearly different RAPD phenotypes of C. pseudopurpurea , each distributed along the river banks of two spatially isolated stream courses. Both phenotypes are present downstream of the confluence. Our results indicate that C. pseudopurpurea originates from two distinct periods of hybridisation between the same parental taxa, and that clonal propagation is most likely the main reproduction method. In line with its hybrid origin, embryos of sampled C. pseudopurpurea caryopses were found to be mostly degraded or unviable over several years. Calamagrostis pseudopurpurea is genetically closer to C. canescens and C. phragmitoides than it is to other studied species, but C. canescens and C. phragmitoides have not been proven to be direct parental taxa of C. pseudopurpurea . Calamagrostis pseudopurpurea should therefore still be treated as a separate species that needs special attention from a conservation point of view.  相似文献   
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Proteomic analysis of formalin-fixed paraffin-embedded (FFPE) tissue would enable retrospective biomarker investigations of this vast archive of pathologically characterized clinical samples that exist worldwide. These FFPE tissues are, however, refractory to proteomic investigations utilizing many state of the art methodologies largely due to the high level of covalently cross-linked proteins arising from formalin fixation. A novel tissue microdissection technique has been developed and combined with a method to extract soluble peptides directly from FFPE tissue for mass spectral analysis of prostate cancer (PCa) and benign prostate hyperplasia (BPH). Hundreds of proteins from PCa and BPH tissue were identified, including several known PCa markers such as prostate-specific antigen, prostatic acid phosphatase, and macrophage inhibitory cytokine-1. Quantitative proteomic profiling utilizing stable isotope labeling confirmed similar expression levels of prostate-specific antigen and prostatic acid phosphatase in BPH and PCa cells, whereas the expression of macrophage inhibitory cytokine-1 was found to be greater in PCa as compared with BPH cells.  相似文献   
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