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1.
Helena Fingerova Ivana Oborna Jiri Novotny Magda Svobodova Jana Brezinova Lenka Radova 《Reproductive biology and endocrinology : RB&E》2009,7(1):118-6
Background
It is generally accepted that oxidative stress is an important factor in male infertility because it may impair the physiological function of spermatozoa at the molecular level. Nevertheless, although several approaches have been reported, the imbalance between production of reactive oxygen species (ROS) and activity of the antioxidant defense system in semen is difficult to investigate and remains poorly understood. 相似文献2.
Maximilian Schmid Bianca Dufner Julius Dürk Konstanze Bedal Kristina Stricker Lukas Ali Prokoph Christoph Koch Anja K. Wege Henner Zirpel Ger van Zandbergen Rupert Ecker Bogdan Boghiu Uwe Ritter 《PloS one》2015,10(10)
Characterization of host-pathogen interactions is a fundamental approach in microbiological and immunological oriented disciplines. It is commonly accepted that host cells start to change their phenotype after engulfing pathogens. Techniques such as real time PCR or ELISA were used to characterize the genes encoding proteins that are associated either with pathogen elimination or immune escape mechanisms. Most of such studies were performed in vitro using primary host cells or cell lines. Consequently, the data generated with such approaches reflect the global RNA expression or protein amount recovered from all cells in culture. This is justified when all host cells harbor an equal amount of pathogens under experimental conditions. However, the uptake of pathogens by phagocytic cells is not synchronized. Consequently, there are host cells incorporating different amounts of pathogens that might result in distinct pathogen-induced protein biosynthesis. Therefore, we established a technique able to detect and quantify the number of pathogens in the corresponding host cells using immunofluorescence-based high throughput analysis. Paired with multicolor staining of molecules of interest it is now possible to analyze the infection profile of host cell populations and the corresponding phenotype of the host cells as a result of parasite load. 相似文献
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Ovaere M Sponer J Sponer JE Herdewijn P Van Meervelt L 《Nucleic acids research》2012,40(15):7573-7583
Altritol nucleic acids (ANAs) are a promising new tool in the development of artificial small interfering ribonucleic acids (siRNAs) for therapeutical applications. To mimic the siRNA:messenger RNA (mRNA) interactions, the crystal structure of the ANA:RNA construct a(CCGUAAUGCC-P):r(GGCAUUACGG) was determined to 1.96?? resolution which revealed the hybrid to form an A-type helix. As this A-form is a major requirement in the RNAi process, this crystal structure confirms the potential of altritol-modified siRNAs. Moreover, in the ANA strands, a new type of intrastrand interactions was found between the O2' hydroxyl group of one residue and the sugar ring O4' atom of the next residue. These interactions were further investigated by quantum chemical methods. Besides hydration effects, these intrastrand hydrogen bonds may also contribute to the stability of ANA:RNA duplexes. 相似文献
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Jiri Moos Petr Kalab Gregory S. Kopf Richard M. Schultz 《Molecular reproduction and development》1994,38(1):91-93
A rapid, nonradioactive method to monitor the ZP2 to ZP2f conversion in the zona pellucida of single mouse eggs has been developed. This assay is based on the chemiluminescent detection of biotinylated ZP2 and ZP2f following electrophoresis under reducing conditions and electrophoretic transfer to Immobilon P. This method is about 10 times faster and detects similar extents of ZP2 to ZP2f conversion following A23187-induced egg activation, when compared to the commonly used radioiodination procedures. © 1994 Wiley-Liss, Inc. 相似文献
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Molecular profiling of CD8 T cells in autochthonous melanoma identifies Maf as driver of exhaustion 下载免费PDF全文