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排序方式: 共有568条查询结果,搜索用时 15 毫秒
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Vojtech Adam Dalibor Huska Jaromir Hubalek Rene Kizek 《Microfluidics and nanofluidics》2010,8(3):329-339
A method that is easy to use, rapid, with a low cost of detecting viral nucleic acid in a biological sample represents the essential tool in targeted therapy. In this study, we report the use of paramagnetic microparticles covered by streptavidin and modified by an oligonucleotide probe with a specific viral sequence labeled by biotin to detect human immunodeficiency virus (HIV) and influenza virus subtype H5N1. The viral nucleic acids were primarily detected by adsorptive transfer stripping technique coupled with square wave voltammetry using carbon paste, hanging mercury drop or carbon nanotubes-based screen-printed working electrodes. Detection limits were estimated for both sequences down to picograms per 3 μl. To isolate the viral sequences, paramagnetic microparticles covered with biotin-labeled oligonucleotides were used. We calculated the yield of isolation for H5N1 and/or HIV sequences, which was defined as “isolated concentration of viral nucleic acid sequence”/“given viral nucleic acid sequence” × 100. We estimated the yield for both sequences as 59%. Moreover, we studied the influence of human serum, dsDNA and non-complementary sequence of nucleic acids on isolation of viral nucleic acids. We also used carbon nanotubes-based screen-printed electrodes coupled with micro-flow instrument to detect viral nucleic acids. We were able to isolate and detect nanogram amounts of nucleic acids. 相似文献
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Dr. Sabine Wicker Prof. Dr. Holger Rabenau Priv.-Doz. Dr. Dr. Rene Gottschalk 《Ethik in der Medizin》2007,19(3):216-218
Ohne Zusammenfassung 相似文献
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S. J. L. Billinge E. S. Božin M. Gutmann H. Takagi 《Journal of Superconductivity and Novel Magnetism》2000,13(5):713-722
We present local structural evidence for the existence of charge inhomogeneities at low temperature in underdoped and optimally doped La2?x Sr x CuO4. The inhomogeneities disappear for x ≥ 0.2. The evidence for the charge inhomogeneities comes from an anomalous increase in the inplane Cu–O bond length distribution in the underdoped samples as well as evidence for CuO6 octahedral tilt inhomogeneities in the intermediate range structure. Preliminary analysis of the temperature dependence of this phenomenon indicates that the inhomogeneities set in at temperatures in the range 60 K < T co < 130 K, which depends on doping. 相似文献
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Refugio Bernardo Garcia‐Reyes Jose Rene Rangel‐Mendez 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(10):1533-1538
BACKGROUND: Agro‐waste materials can be used as biosorbents of heavy metals in aqueous solution. However, it is necessary to further study the contribution of agro‐waste materials components (i.e. hemicelluloses, cellulose, and lignin) to the heavy metal ions removal from aqueous solution to better understand the biosorption mechanism, and also based on the biosorbents main components, to predict their potential to remove heavy metals. RESULTS: Cellulose is contained in major proportion (greater than 46%) in the agro‐waste materials reported herein compared with hemicelluloses (from 12% to 26%), lignin (varying from 3% to 10%), and other compounds (22% to 30%) that were removed after the neutral detergent fiber procedure. The identified functional groups in agro‐waste materials and their fractions included hydroxyl, carboxyl, and nitrogen‐containing compounds. Lignin contributed in higher proportion than hemicelluloses to Cr (III) adsorption capacity in both sorghum straw and oats straw. On the other hand lignin was the main fraction responsible for Cr (III) adsorption in agave bagasse. CONCLUSION: Hemicelluloses and lignin were the main contributors to Cr (III) removal from aqueous solution, and cellulose contained in the agro‐waste adsorbents studied did not seem to participate. Copyright © 2009 Society of Chemical Industry 相似文献
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Lin Song Monika Rawolle Nuri Hohn Jochen S. Gutmann Henrich Frielinghaus Peter Müller‐Buschbaum 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(30)
For many applications, mesoporous titania nanostructures are exposed to water or need to be backfilled via infiltration with an aqueous solution, which can cause deformations of the nanostructure by capillary forces. In this work, the degree of deformation caused by water infiltration in two types of mesoporous, nanostructured titania films exposed to water vapor is compared. The different types of nanostructured titania films are prepared via a polymer template assisted sol–gel synthesis in conjunction with a polymer‐template removal at high‐temperatures under ambient conditions versus nitrogen atmosphere. Information about surface and inner morphology is extracted by scanning electron microscopy and grazing incidence small‐angle neutron scattering (GISANS) measurements, respectively. Furthermore, complementary information on thin film composition and porosity are probed via X‐ray reflectivity. The backfilling induced deformation of near surface structures and structures inside the mesoporous titania films is determined by GISANS before and after D2O infiltration. The respective atmosphere used for template removal influences the details of the titania nanostructure and strongly impacts the degree of water induced deformation. Drying of the films shows reversibility of the deformation. 相似文献