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41.
Lu H  Conneely G  Pravda M  Guilbault GG 《Steroids》2006,71(9):760-767
Electrochemical based immunosensors for the detection of boldenone and methylboldenone in bovine urine were described in this paper. The immunosensors were fabricated by immobilizing boldenone-bovine serum albumin conjugate on the surface of screen-printed electrodes (SPEs), and followed by the competition between the free analyte and coating conjugate with corresponding antibodies. The use of anti-species IgG-horseradish peroxidase conjugate determined the degree of competition. The electrochemical technique chosen was chronoamperometry, performed at a potential of +100 mV whereby the product of the catalysis of 3,3′,5,5′-tetramethylbenzidine undergoes reduction produced by the enzyme label. The limits of detection of assay were 30.9 ± 4.3 pg ml−1 for boldenone and 120.2 ± 8.2 pg ml−1 for methylboldenone, respectively. Results of repeated analysis of each androgen carried out using three different batches of electrodes indicate suitable repeatability (EC50 = 1.0 ± 0.3 ng ml−1 (n = 3, N = 3), R2 = 0.969, R.S.D. = 9.6% for boldenone and 1.5 ± 0.3 ng ml−1, 0.971, 10.5% for methylboldenone, respectively). Urine samples were determined directly after a single dilution step, omitting extraction and hydrolysis. This method offers the advantage to pick up both boldenone and its major metabolites in an efficient manner due to the high cross-reactivity pattern of α-boldenone with this antibody. The concentration of methylboldenone in urine detected by developed methods does indicate methylboldenone administration to heifers. Gas chromatography coupled to mass spectrometry analysis was performed to quantitate the individual metabolites present in urine samples, and results were validated with both ELISA and immunosensor data.  相似文献   
42.
This article applies a combined input−output and life cycle inventory (LCI) method to the calculation of emissions and material requirements of the Czech economy in 2003. The main focus is on materials and emissions embodied in the international trade of the Czech Republic. Emissions and material extraction avoided due to imports are calculated according to an input−output approach that assumes the same production technology for imports as for domestic production. Because not all products are provided by the domestic economy, the LCI data are incorporated into the monetary input−output model.
The results show that incorporating the LCI data into an input−output model is reasonable. The emissions embodied in the international trade of the Czech Republic are comparable to the domestic emissions. We compare the economy-wide material flow indicators, such as direct material input, domestic material consumption, and physical trade balance, to their raw material equivalents. The results of our calculation show that the Czech Republic exerts environmental pressure on the environment in other countries through international trade.
We argue that raw material equivalents should be used to express the flows across national boundaries. Furthermore, we recommend a raw material consumption indicator for international comparisons.  相似文献   
43.
The hydrogen isotope-effect that occurs in vitro during myo-inositol 1-phosphate synthase-catalyzed conversion of d-[5-3H]glucose 6-phosphate into myo-[2-3H]inositol 1-phosphate has been used to compare the functional role of the nucleotide sugar oxidation-pathway with that of the myo-inositol oxidation-pathway in germinating lily pollen. Results reveal a significant difference between the 3H/14C ratios of glucosyl and galactosyluronic residues from pectinase-amyloglucosidase hydrolyzates of the 70 % ethanol-insoluble fraction of d-[5-3H, 1-14-C]glucose-labeled, germinating lily pollen. This isotope effect at C-5 of d-glucose that occurred during its conversion into d-galactosyluronic residues of pectic substance is not explained by loss of 3H when UDP-d-[5-3H, 1-14C]glucose is oxidized by UDP-d-glucose dehydrogenase from germinating lily pollen. The evidence obtained from this study favors a functional role for the myo-inositol oxidation pathway during in vivo conversion of glucose into galactosyluronic residues of pectin in germinating lily pollen.  相似文献   
44.
Prickly lettuce (Lactuca serriola) is world-wide distributed and very variable species generally considered as a progenitor of the cultivated lettuce (Lactuca sativa). Altogether, 50 populations of L. serriola were characterized by means of amplified fragment length polymorphism (AFLP) and by isozyme analysis. Relationships among individuals and populations were examined by applying the unweighted pair-group method with the arithmetic averages (UPGMA) clustering algorithm, principal coordinate analysis (PCA) and the Nei's gene diversity index. The studied set of populations split into three main groups based on the AFLP polymorphism analysis. The first group contained L. sativa (control). The second group comprised two L. serriola accessions; one of them was identified as L. serriola f. integrifolia and the other as a mixture of two L. serriola forms. The largest and the most diverse third group contained the remaining L. serriola accessions. The population clustering corresponded approximately to their geographical distribution in Europe. At least five distinct geographic groups were recognised: 1) Northern European; 2) Slovenian; 3) very heterogeneous Central and Western European (mostly north of the Alps); 4) Mediterranean; 5) prevalence of L. serriola f. integrifolia, mostly comprising accessions from the United Kingdom and the Netherlands. This study showed that accessions originating in various eco-geographical conditions of Europe differ significantly in their genetic and protein polymorphism, as well as in morphology. Some European L. serriola populations (e.g. from Scandinavia and United Kingdom/British Isles/) seems to be isolated and homogeneous; in contrast, populations occurring in Central Europe are very diverse and genetically overlapping.  相似文献   
45.
This article deals with the economy‐wide material flows in the Czech Republic in 1990–2006. It presents in brief the overall trends of the material flow indicators in 1990–2002. The major part of the article is focused on the years 2002–2006, which immediately preceded and followed the accession of the Czech Republic to the European Union in 2004. It is shown that this accession had quite a significant impact on the volume and character of the material flows of the Czech Republic. The accession was beneficial from an economic point of view, as it allowed for an increased supply of materials needed for economic growth. Furthermore, it was accompanied by an improvement in the efficiency of material transformation into economic output. From an environmental and broader sustainability point of view, however, this accession brought about some controversial outcomes. There was a significant increase in the net export of environmental pressure, on one hand, and an increase in net additions to the physical stock of the economy, on the other. Although the former is controversial from the viewpoint of equity in sharing area and resources, the latter places an additional burden on future generations because all physical stocks will turn into waste and emissions at some point, when their life span expires.  相似文献   
46.
Nitrous acid deamination of 2-amino-1,6-anhydro-2-deoxy-β-D-glucopyranose (1) in the presence of weakly acidic, cation-exchange resin gave 1,6:2,3-dianhydro-β-D-mannopyranose (3) and 2,6-anhydro-D-mannose (6), characterized, respectively, as the 4-acetate of 3 and the per-O-acetylated reduction product of 6, namely 2,3,4,6- tetra-O-acetyl-1,5-anhydro-D-mannitol, obtained in the ratio of 7:13. Comparative deaminatior of the 4-O-benzyl derivative of 1 led to similar qualitative results. Deamination of 3-amino-1,6-anhydro-3-deoxy-β-D-glucopyranose gave 1,6:2,3- and 1,6:3,4-dianhydro-β-D-allopyranose (13 and 16), characterized as the corresponding acetates, obtained in the ratio of 31:69, as well as the corresponding p-toluenesulfonates. Deamination of 4-amino-1,6-anhydro-4-deoxy-β-D-glucopyranose and of its 2-O-benzyl derivative gave the corresponding 1,6:3,4-D-galacto dianhydrides as the only detectable products. 2,5-Anhydro-D-glucose, characterized as the 1,3,4,6-tetra-O- acetyl derivative of the corresponding anhydropolyol, was obtained in 39% yield from the same deamination reaction performed on 2-amino-1,6-anhydro-2-deoxy-β-D- mannopyranose (24). In 90% acetic acid, the nitrous acid deamination of 24, followed by per-O-acetylation, gave only 1,3-4-tri-O-acetyl-2,5-anhydro-α-D-glucoseptanose. In the case of 1,6-anhydro-3,4-dideoxy-3,4-epimino-β-D-altropyranose, only the corresponding glycosene was formed, namely, 1,6-anhydro-3,4-dideoxy-β-D-threo--hex-3-enopyranose.  相似文献   
47.
The effect of protein moiety on the conformation of 16S and 23S RNA of the E.coli ribosome has been studied by circular dichroic spectroscopy. Both rRNAs possess a comparable net content of ordered secondary structure which remains unchanged after association with ribosomal proteins into “core” particles or into complete 30S and 50S subunits, respectively. However, differences found in the stability and the cooperativity of melting of free and protein-associated rRNAs imply protein-caused variations in the distribution of the intramolecular hairpin stems and loops and/or changes in long range tertiary interactions which appear to be different for both rRNAs. While 23S RNA is maximally stabilized on the large subunit by the full set of proteins, 16S RNA on the complete small subunit shows lower stability but higher cooperativity in melting.  相似文献   
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50.
Infection with Chloromyxum careni Mutschmann, 1999 was found in the Asian horned frog Megophrys nasuta from Malaysia and Indonesia. Kidney was the only organ infected. Coelozoic plasmodia up to 300 μm were localized in Bowman's space, embracing the glomerulus from all sides, or rarely in lumina of renal tubules. Plasmodia are polysporic, containing disporic pansporoblasts. Myxospores observed by light microscopy are colorless, variable in shape and size, measuring 6.0-8.5 × 5.0-6.5 μm, composed of two symmetrical valves joined by a meridian suture, containing four pyriform polar capsules 3.0-4.0 × 2.5-3.0 μm and a single sporoplasm. Each valve possesses 14-24 (median 21) fine longitudinal ridges clearly visible only in scanning electron microscopy. Rarely, atypical spores with a markedly pointed posterior pole and only 6-10 surface ridges are present in plasmodia together with typical spores. Both small subunit (SSU) and large subunit (LSU) rRNA gene sequences possess extremely long GU-rich inserts. In all SSU and LSU rDNA-based phylogenetic analyses, C. careni clustered as a distinct basal branch to the Myxobolus+Myxidium lieberkuehni clade, out of the marine Chloromyxum clade containing Chloromyxum leydigi, the type species of the genus. These morphological and phylogenetic data suggest erection of a new genus for the C. careni lineage, but we conservatively treat it as a Chloromyxum sensu lato until more information is available.  相似文献   
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