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141.
Dyes belonging to the mono-, di-, tri- and poly-azo as well as anthraquinonic and mono-azo Cr-complexed classes, chosen among the most utilized in textile applications, were employed for a comparative enzymatic decolorization study using the extracellular crude culture extracts from the white rot fungus Funalia (Trametes) trogii grown on different culture media and activators able to trigger different levels of expression of oxidizing enzymes: laccase and cellobiose dehydrogenase. Laccase containing extracts were capable to decolorize some dyes from all the different classes analyzed, whereas the recalcitrant dyes were subjected to the combined action of laccase and the chemical mediator HBT, or laccase plus cellobiose dehydrogenase. Correlations among the decolorization degree of the various dyes and their electronic and structural diversities were rationalized and discussed. The utilization of cellobiose dehydrogenase in support to the activity of laccase for the decolorization of azo textile dyes resulted in substantial increases in decolorization for all the refractory dyes proving to be a valid alternative to more expensive and less environmentally friendly chemical treatments of textile dyes wastes. 相似文献
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Gram-Negative Bacterial Lipopolysaccharide Retention by a Positively Charged New-Generation Filter 总被引:1,自引:1,他引:0 下载免费PDF全文
Ilaria Bononi Veronica Balatti Soccorso Gaeta Mauro Tognon 《Applied microbiology》2008,74(20):6470-6472
Removing endotoxins is an important target in the pharmaceutical industry and in clinical practice. A filter introduced into an intravenous line prevents microbiological contamination, but to date no filters have retained bacterial endotoxins. In our study, we assayed a new-generation filter which is able to capture endotoxins from solutions. 相似文献
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Rognoni Franco Gianesello Daniela Maddalena Fabrizio Giuntini Ilaria Herbst Detlev 《Cytotechnology》1999,29(1):11-25
Anti PSA monoclonal antibodies for diagnostic use were produced in an in vitro system. After purification using Protein G affinity chromatography a percentage of about 10% of antibody aggregates remained. The use of monoclonal antibodies containing aggregates as a capture antibody in a diagnostic kit reduces the performance of the test making it often unacceptable. The aggregates could be eliminated using gel filtration chromatography but, in that way, the final recovery of the whole production process was only about 50%. Aggregation is favoured when the working pH is near to the isoelectric point of the antibody. We varied the culture medium composition, modifying pH and osmolarity. We tested different values of pH and osmolarity: 7.1, 7.5, 8.0, 8.5 for pH, and 300, 340, 367, 395 mOsm/kg H2O for osmolarity. By modification of the cell culture medium we obtained a significant decrease of monoclonal antibody aggregates in the production cycle. In this way we achieved higher recovery rate and could avoid gel filtration polishing step. The experiments were performed in two stages: first in culture flasks changing one parameter in each experiment, and then in spinner bottle using the best conditions obtained in the first stage. During scale up we used the modifications achieved from the experiment showed in this paper in our production by hollow fibre bioreactor with positive results. 相似文献
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Fabio Moda Thanh-Nhat T. Le Suzana Auli? Edoardo Bistaffa Ilaria Campagnani Tommaso Virgilio Antonio Indaco Luisa Palamara Olivier Andréoletti Fabrizio Tagliavini Giuseppe Legname 《PLoS pathogens》2015,11(12)
Prions are infectious proteins that possess multiple self-propagating structures. The information for strains and structural specific barriers appears to be contained exclusively in the folding of the pathological isoform, PrPSc. Many recent studies determined that de novo prion strains could be generated in vitro from the structural conversion of recombinant (rec) prion protein (PrP) into amyloidal structures. Our aim was to elucidate the conformational diversity of pathological recPrP amyloids and their biological activities, as well as to gain novel insights in characterizing molecular events involved in mammalian prion conversion and propagation. To this end we generated infectious materials that possess different conformational structures. Our methodology for the prion conversion of recPrP required only purified rec full-length mouse (Mo) PrP and common chemicals. Neither infected brain extracts nor amplified PrPSc were used. Following two different in vitro protocols recMoPrP converted to amyloid fibrils without any seeding factor. Mouse hypothalamic GT1 and neuroblastoma N2a cell lines were infected with these amyloid preparations as fast screening methodology to characterize the infectious materials. Remarkably, a large number of amyloid preparations were able to induce the conformational change of endogenous PrPC to harbor several distinctive proteinase-resistant PrP forms. One such preparation was characterized in vivo habouring a synthetic prion with novel strain specified neuropathological and biochemical properties. 相似文献
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Elisabetta Barresi Chiara Giacomelli Simona Daniele Ilaria Tonazzini Marco Robello Silvia Salerno Ilaria Piano Barbara Cosimelli Giovanni Greco Federico Da Settimo Claudia Martini Maria Letizia Trincavelli Sabrina Taliani 《Bioorganic & medicinal chemistry》2018,26(22):5885-5895
The expression levels and the subcellular localization of adenosine receptors (ARs) are affected in several pathological conditions as a consequence of changes in adenosine release and metabolism. In this respect, labelled probes able to monitor the AR expression could be a useful tool to investigate different pathological conditions. Herein, novel ligands for ARs, bearing the fluorescent 7-nitrobenzofurazan (NBD) group linked to the N1 (1,2) or N10 (3,4) nitrogen of a triazinobenzimidazole scaffold, were synthesized. The compounds were biologically evaluated as fluorescent probes for labelling A1 and A2B AR subtypes in bone marrow-derived mesenchymal stem cells (BM-MSCs) that express both receptor subtypes. The binding affinity of the synthetized compounds towards the different AR subtypes was determined. The probe 3 revealed a higher affinity to A1 and A2B ARs, showing interesting spectroscopic properties, and it was selected as the most suitable candidate to label both AR subtypes in undifferentiated MSCs.Fluorescence confocal microscopy showed that compound 3 significantly labelled ARs on cell membranes and the fluorescence signal was decreased by the cell pre-incubation with the A1 AR and A2B AR selective agonists, R-PIA and BAY 60-6583, respectively, thus confirming the specificity of the obtained signal. In conclusion, compound 3 could represent a useful tool to investigate the expression pattern of both A1 and A2B ARs in different pathological and physiological processes. Furthermore, these results provide an important basis for the design of new and more selective derivatives able to monitor the expression and localization of each different ARs in several tissues and living cells. 相似文献
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Federica Ferrigno Ilaria Biancofiore Savina Malancona Simona Ponzi Giacomo Paonessa Rita Graziani Alberto Bresciani Nadia Gennari Annalise Di Marco Marcel Kaiser Vincenzo Summa Steven Harper Jesus M. Ontoria 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3689-3692
The identification of a new series of growth inhibitors of Trypanosoma brucei rhodesiense, causative agent of Human African Trypanosomiasis (HAT), is described. A selection of compounds from our in-house compound collection was screened in vitro against the parasite leading to the identification of compounds with nanomolar inhibition of T. brucei growth. Preliminary SAR on the hit compound led to the identification of compound 34 that shows low nanomolar parasite growth inhibition (T. brucei EC50 5?nM), is not cytotoxic (HeLa CC50?>?25,000?nM) and is selective over other parasites, such as Trypanosoma cruzi and Plasmodium falciparum (T. cruzi EC50 8120?nM, P. falciparum EC50 3624?nM). 相似文献