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71.
This paper presents results from a research which analyzed the reporting on genetically modified crops and food in the Hungarian tabloids and political papers with the highest circulation from 1 May 2007 to 31 October 2009. Both quantitative and qualitative media analysis was conducted. It was found that in contrast to some Western countries the issue had low salience in the investigated period; it featured especially marginally in the tabloids. Two distinct valenced frames could be differentiated: a dominant ANTI-GM (Threat) frame – which was particularly frequent compared to what has been found for some other countries, and a minority PRO-GM (Advancement and Benefits) frame. Despite a range of similarities with what had been reported by previous research from some other countries, argumentation on the GMO topic in the Hungarian press had several distinct characteristics, one of which was the relative prominence of economic arguments against the technology.  相似文献   
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Phosphodiesterases are drug targets for treating various diseases. Inhibition of these can increase cAMP and cGMP levels, which can affect a variety of physiological responses. Here we report a new method for determining PDE activity by combining high-performance liquid chromatography and tandem mass spectrometry. Characteristic peaks of the substrates, cGMP or cAMP and products, GMP or AMP, were identified in positive-ion electrospray ionization using multiple reaction monitoring. The method can be applied to determine activity of PDE inhibitors. Our results showed that this new method was fast, sensitive and highly reproducible.  相似文献   
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Intrapulmonary application of perfluorocarbons (PFC) in acute lung injury is associated with anti-inflammatory effects. A direct impact on leukocytic function may be involved. To further elucidate PFC effects on cellular activation, we compared in an in vitro model the response of concanavalin A (ConA)-stimulated lymphocytes and monocytes exposed to perfluorohexane. We hypothesized that perfluorohexane attenuates the action of the lectin ConA by altering stimulant-receptor interaction on the cell surface. Mononuclear blood cells were stimulated by incubation with ConA in the presence of different amounts of perfluorohexane. The response of lymphocytes and monocytes was determined by means of IL-2 secretion and tissue factor (TF) expression, respectively. The influence of perfluorohexane on cell-surface binding of fluorescence-labeled ConA was studied using flow cytofluorometry and fluorescence microscopy. Perfluorohexane itself did not induce a cellular activation but significantly inhibited both monocytic TF expression and, to a far greater extent, IL-2 secretion of ConA-stimulated mononuclear blood cells. The effect of perfluorohexane was due neither to an alteration of cell viability nor to a binding of the stimulant. The amount of cell surface-bound ConA was not altered by perfluorohexane, and the overall pattern of ConA receptor rearrangement did not differ between controls and treated cells. In the present study, we provide further evidence for an anti-inflammatory effect of PFC that might be beneficial in states of pulmonary hyperinflammation. A PFC-induced alteration of stimulant-receptor interaction on the surface membrane does not seem to be the cause of attenuated cell activation.  相似文献   
76.
Pulmonary fibrosis is characterized by excessive extracellular matrix deposition with concomitant loss of gas exchange units, and endothelin-1 (ET-1) has been implicated in its pathogenesis. Increased levels of ET-1 from tissues and bronchoalveolar lavage have been reported in patients with pulmonary fibrosis and in animal models after intratracheal bleomycin. We characterized the cellular distribution of alveolar ET receptors by immunohistochemistry in bleomycin-induced pulmonary fibrosis in the rat and determined the regulation by bleomycin of ET receptor mRNA expression in isolated alveolar macrophages and rat lung fibroblasts. We found significant increases in the numbers of fibroblasts and macrophages at day 7 compared to day 28 and control animals. ET(B) receptor immunoreactivity was observed on fibroblasts and invading monocytes. Isolated fibroblasts expressed both ET(A) and ET(B) receptor mRNA, and ET(A) receptor mRNA was upregulated by bleomycin. Isolated resident alveolar macrophages expressed neither ET(A) nor ET(B) receptor mRNA which were also not induced by bleomycin. We conclude that, while ET(B) receptor stimulation of fibroblasts and monocytes recruited during bleomycin-induced lung injury exerts antagonistic effects on fibroblast collagen synthesis, the observed increase in the number of fibroblasts in vivo and upregulation of fibroblast ET(A) receptor mRNA by bleomycin in vitro point to a predominance of the profibrotic effects of ET receptor engagement.  相似文献   
77.
PURPOSE: To present the postoperative radiotherapy technique in children with medulloblastoma, and analyse the effectiveness of radiotherapy and the survival data. MATERIALS AND METHODS: 66 consecutive children (45 male and 21 female) received postoperative chemotherapy and radiotherapy between 1986 and 1998. The mean age was 8.3 years. The radiotherapy was performed with linear accelerator 9MV X-ray irradiation. The high risk patients received 36 Gy craniospinal irradiation, the low risk patients recived 30 Gy. The boost irradiation to the posterior fossa was 20 Gy in both patient groups. The patients received multi-drug chemotherapy immediately after the tumor resection. The radiotherapy started 6-8 weeks after the operation. RESULTS: All 66 patients were evaluated. The mean follow-up time was 45.4 months. The chance of cure is higher at age 8 or more, and less favorable under age 8. After 60 months 68.6% of children under age 8 and 75.9% older than 8 are alive. 20 children (64.5%) are alive after radical tumorectomy and 11 died. The 5 year overall survival was 71%. Recurrence was observed in 23/66 cases, it was the most frequent cause of death. Local failure was in posterior fossa in 15 patients (68.2%). CONCLUSION: The radicality of operation had no significant influence to the overall survival. The tumor stage, age of patients, risk group and metastases are important prognostic factors.  相似文献   
78.

Spores of the genus Bacillus are able to resist ionizing radiations and therefore they are a suitable biological model for studies in Astrobiology, i.e. the multidisciplinary approach to the study of the origin and evolution of life on Earth and in the universe. The resistance to γ-radiation is an important issue in Astrobiology in relation to the search for bacterial species that could adapt to life in space. This study investigates the resistance of spores of the thermophilic bacteria Parageobacillus thermantarcticus to γ-rays. The analysis of spores’ response to irradiation at a molecular level is performed by means of Raman spectroscopy that allows to get insights in the sequence of events taking place during inactivation. The role of the γ-rays’ dose in the inactivation of spores is also investigated, allowing to highlight the mechanism(s) of inactivation including DNA damage, protein denaturation and calcium dipicolinate levels.

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79.
Multiple forms of s1-casein were identified in the four major ruminant species by structural characterization of the protein fraction. While s1-casein phenotypes were constituted by a mixture of at least seven molecular forms in ovine and caprine species, there were only two forms in bovine and water buffalo species. In ovine and caprine forms the main component corresponded to the 199-residue-long form, and the deleted proteins differed from the complete one by the absence of peptides 141–148, 110–117, or Gln78, or a combination of such deletions. The deleted segments corresponded to the sequence regions encoded by exons 13 and 16, and by the first triplet of exon 11 (CAG), suggesting that the occurrence of the short protein forms is due to alternative skipping, as previously demonstrated for some caprine and ovine phenotypes. The alternative deletion of Gln78 in s1-casein, the only form common to the milk of all the species examined and located in a sequence region joining the polar phosphorylation cluster and the hydrophobic C-terminal domain of the protein, may play a functional role in the stabilization of the milk micelle structure.  相似文献   
80.
A tobacco plant was illuminated for 5h in an atmosphere containing (13)CO(2) and then maintained for 10 days under standard greenhouse conditions. Nicotine, glucose, and amino acids from proteins were isolated chromatographically. Isotopologue abundances of isolated metabolites were determined quantitatively by NMR spectroscopy and mass spectrometry. The observed non-stochastic isotopologue patterns indicate (i) formation of multiply labeled photosynthetic carbohydrates during the (13)CO(2) pulse phase followed by (ii) partial catabolism of the primary photosynthetic products, and (iii) recombination of the (13)C-labeled fragments with unlabeled intermediary metabolites during the chase period. The detected and simulated isotopologue profiles of glucose and amino acids reflect carbon partitioning that is dominated by the Calvin cycle and glycolysis/glucogenesis. Retrobiosynthetic analysis of the nicotine pattern is in line with its known formation from nicotinic acid and putrescine via aspartate, glyceraldehyde phosphate and alpha-ketoglutarate as basic building blocks. The study demonstrates that pulse/chase labeling with (13)CO(2) as precursor is a powerful tool for the analysis of quantitative aspects of plant metabolism in completely unperturbed whole plants.  相似文献   
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