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811.
Metabolism of polychlorinated biphenyls by Solanum nigrum hairy root clone SNC-9O and analysis of transformation products 总被引:1,自引:0,他引:1
Kučerová Petra Macková Martina Chromá Ludmila Burkhard Jiri Tríska Jan Demnerová Katerina Macek Tomáš 《Plant and Soil》2000,225(1-2):109-115
The study investigates aspects of PCB metabolism by a hairy root culture of Solanum nigrum L. (clone SNC-9O) in vitro. Standard conditions were established for efficient, up to 72% PCB conversion (22 individual PCB congeners examined in commercial
mixture Delor 103, 5 g fresh biomass in 100 ml media shaken with 5 mg PCB for 14 days). The conversion products formed from
three monochlorobiphenyls were monohydroxychlorobiphenyls and dihydroxychlorobiphenyls, while six dichlorobiphenyls yielded
different monohydroxydichlorobiphenyls. Efficiency of the transformation of individual PCB congeners was evaluated together
with phytotoxic effect on the clone SNC-9O. Major metabolites of monochlorobiphenyls analysed after extraction from biomass
were hydroxylated at the position 4, and 4′, respectively.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
812.
Veiko Krauss Anne Fassl Petra Fiebig Ina Patties Heinz Sass 《BMC evolutionary biology》2006,6(1):18-15
Background
In eukaryotes, histone H3 lysine 9 (H3K9) methylation is a common mechanism involved in gene silencing and the establishment of heterochromatin. The loci of the major heterochromatic H3K9 methyltransferase Su(var)3-9 and the functionally unrelated γ subunit of the translation initiation factor eIF2 are fused in Drosophila melanogaster. Here we examined the phylogenetic distribution of this unusual gene fusion and the molecular evolution of the H3K9 HMTase Su(var)3-9. 相似文献813.
Petra Klepac Laura W. Pomeroy Ottar N. Bj?rnstad Thijs Kuiken Albert D.M.E. Osterhaus Jolianne M. Rijks 《Proceedings. Biological sciences / The Royal Society》2009,276(1666):2469-2476
Heterogeneities in transmission among hosts can be very important in shaping infectious disease dynamics. In mammals with strong social organization, such heterogeneities are often structured by functional stage: juveniles, subadults and adults. We investigate the importance of such stage-related heterogeneities in shaping the 2002 phocine distemper virus (PDV) outbreak in the Dutch Wadden Sea, when more than 40 per cent of the harbour seals were killed. We do this by comparing the statistical fit of a hierarchy of models with varying transmission complexity: homogeneous versus heterogeneous mixing and density- versus frequency-dependent transmission. We use the stranding data as a proxy for incidence and use Poisson likelihoods to estimate the ‘who acquires infection from whom’ (WAIFW) matrix. Statistically, the model with strong heterogeneous mixing and density-dependent transmission was found to best describe the transmission dynamics. However, patterns of incidence support a model of frequency-dependent transmission among adults and juveniles. Based on the maximum-likelihood WAIFW matrix estimates, we use the next-generation formalism to calculate an R0 between 2 and 2.5 for the Dutch 2002 PDV epidemic. 相似文献
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815.
Manfred Rizzi Petra Erlemann Ngoc-Anh Bui-Thanh Hanswerner Dellweg 《Applied microbiology and biotechnology》1988,29(2-3):148-154
Summary Xylose reductase from the xylose-fermenting yeastPichia stipitis was purified to electrophoretic homogeneity via ion-exchange, gel and affinity chromatography. At physiological pH values the thermodynamic equilibrium constant was determined to be 0.575x1010 (l·mol-1). Product inhibiton studies are reported which clearly show that the kinetic mechanism of the xylose reductase is ordered-bi-bi with isomerisation of a stable enzyme form. 相似文献
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Genome‐wide identification of urinary cell‐free microRNAs for non‐invasive detection of bladder cancer 下载免费PDF全文
Jaroslav Juracek Barbora Peltanova Jan Dolezel Michal Fedorko Dalibor Pacik Lenka Radova Petra Vesela Marek Svoboda Ondrej Slaby Michal Stanik 《Journal of cellular and molecular medicine》2018,22(3):2033-2038
Urinary microRNAs (miRNAs) are emerging as clinically useful tool for early and non‐invasive detection of various types of cancer including bladder cancer (BCA). In this study, 205 patients with BCA and 99 healthy controls were prospectively enrolled. Expression profiles of urinary miRNAs were obtained using Affymetrix miRNA microarrays (2578 miRNAs) and candidate miRNAs further validated in independent cohorts using qRT‐PCR. Whole‐genome profiling identified 76 miRNAs with significantly different concentrations in urine of BCA compared to controls (P < 0.01). In the training and independent validation phase of the study, miR‐31‐5p, miR‐93‐5p and miR‐191‐5p were confirmed to have significantly higher levels in urine of patients with BCA in comparison with controls (P < 0.01). We further established 2‐miRNA‐based urinary DxScore (miR‐93‐5p, miR‐31‐5p) enabling sensitive BCA detection with AUC being 0.84 and 0.81 in the training and validation phase, respectively. Moreover, DxScore significantly differed in the various histopathological subgroups of BCA and decreased post‐operatively. In conclusion, we identified and independently validated cell‐free urinary miRNAs as promising biomarkers enabling non‐invasive detection of BCA. 相似文献
819.
Petra Lassuthova Adriana P. Rebelo Gianina Ravenscroft Phillipa J. Lamont Mark R. Davis Fiore Manganelli Shawna M. Feely Chelsea Bacon Dana Šafka Brožková Jana Haberlova Radim Mazanec Feifei Tao Cima Saghira Lisa Abreu Steve Courel Eric Powell Elena Buglo Dana M. Bis Stephan Zuchner 《American journal of human genetics》2018,102(3):505-514
820.