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M Wandzilak P G?uszko W Królikowski A Prokop J Soja A Szczeklik 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1990,45(36-37):749-751
Netilmicin - a semisynthetic aminoglycoside - was administered to 33 patients with the acute or chronic lower respiratory tract or pulmonary infections in a daily dose of 5 mg/kg body weight for 10 days. A principle criterium of patients classification to netilmicin therapy were sensitive bacterial strains either in sputum or in BAL liquid. A significant clinical improvement was noted in 88% of the treated patients. However, elimination of pathogens from the sputum was achieved only in 52% of these patients. No improvement was observed in 4% of the treated patients. No adverse reactions were noted. Netilmicin proved safe and effective antibacterial agent in patients with respiratory infections. 相似文献
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The synthesis of the 8,12-secoprostaglandin E1 analogs and is reported. 相似文献
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Biochar Decelerates Soil Organic Nitrogen Cycling but Stimulates Soil Nitrification in a Temperate Arable Field Trial 总被引:1,自引:0,他引:1
Judith Prommer Wolfgang Wanek Florian Hofhansl Daniela Trojan Pierre Offre Tim Urich Christa Schleper Stefan Sassmann Barbara Kitzler Gerhard Soja Rebecca Clare Hood-Nowotny 《PloS one》2014,9(1)
Biochar production and subsequent soil incorporation could provide carbon farming solutions to global climate change and escalating food demand. There is evidence that biochar amendment causes fundamental changes in soil nutrient cycles, often resulting in marked increases in crop production, particularly in acidic and in infertile soils with low soil organic matter contents, although comparable outcomes in temperate soils are variable. We offer insight into the mechanisms underlying these findings by focusing attention on the soil nitrogen (N) cycle, specifically on hitherto unmeasured processes of organic N cycling in arable soils. We here investigated the impacts of biochar addition on soil organic and inorganic N pools and on gross transformation rates of both pools in a biochar field trial on arable land (Chernozem) in Traismauer, Lower Austria. We found that biochar increased total soil organic carbon but decreased the extractable organic C pool and soil nitrate. While gross rates of organic N transformation processes were reduced by 50–80%, gross N mineralization of organic N was not affected. In contrast, biochar promoted soil ammonia-oxidizer populations (bacterial and archaeal nitrifiers) and accelerated gross nitrification rates more than two-fold. Our findings indicate a de-coupling of the soil organic and inorganic N cycles, with a build-up of organic N, and deceleration of inorganic N release from this pool. The results therefore suggest that addition of inorganic fertilizer-N in combination with biochar could compensate for the reduction in organic N mineralization, with plants and microbes drawing on fertilizer-N for growth, in turn fuelling the belowground build-up of organic N. We conclude that combined addition of biochar with fertilizer-N may increase soil organic N in turn enhancing soil carbon sequestration and thereby could play a fundamental role in future soil management strategies. 相似文献
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Bo P. Weidema Niels Frees Anne-Merete Nielsen 《The International Journal of Life Cycle Assessment》1999,4(1):48-56
Marginal technologies are defined as the technologies actually affected by the small changes in demand typically studied in
prospective, comparative life cycle assessments. Using data on marginal technologies thus give the best reflection of the
actual consequences of a decision. Furthermore, data on marginal technologies are easier to collect, more precise, and more
stable in time than data on average technologies. A 5-step procedure is suggested to identify the marginal technologies. The
step-wise procedure first clarifies the situation in which the marginal should apply, and then identifies what specific technology
is marginal in this situation. The procedure is illustrated in two examples: European electricity production and pulp and
paper production. 相似文献
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Reproductive failure in Arabidopsis thaliana under transient carbohydrate limitation: flowers and very young siliques are jettisoned and the meristem is maintained to allow successful resumption of reproductive growth 下载免费PDF全文
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Ozone may affect leaf photosynthesis even before visible symptoms become apparent. This study had the objective to test several parameters of chlorophyll fluorescence and leaf gas exchange for their usefulness as indicators of latent ozone injury in the field. Container-grown apple trees (Malus domestica Borkh. cv. Golden Delicious) were exposed to four different ozone levels in open-top chambers. Identical leaves were analyzed in fixed-time intervals for the characteristics of fast fluorescence induction kinetics in vivo. By using high-time resolution, characteristic parameters describing the early photochemical events could be calculated according to the JIP-test. Parameters responsive to the different ozone treatments showed clear dependence on the accumulated ozone dose. Ozone exposure immediately preceding the measurements was more important for the extent of the physiological effects than the total accumulated ozone dose. The most sensitive parameters were the turnover number N (indicating how many times QA has to be reduced for full reduction of all acceptors; positively correlated to ozone dose) and D0, the density of reaction centres per leaf area (negatively correlated to ozone dose). Most parameters analyzed showed clearer responses to ozone on the adaxial than on the abaxial surface of the leaf. Changes in the parameter N were better correlated to ozone doses with low cut-offs (AOT00 and AOT20), whereas changes in D0 and in the specific electron fluxes per reaction centre were mainly influenced by ozone doses with high cut-offs (AOT80 and AOT100). Leaf gas exchange analyses revealed a higher ozone sensitivity in carboxylation efficiency than in light utilization efficiency and in the rate of light-saturated net photosynthesis. All ozone-induced photosynthetic effects were observed in leaves showing no sign of visible leaf injury. This study identified fluorescence parameters that could be useful for rapid monitoring and early detection of latent leaf injury by ozone. 相似文献
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Soja Sreenivasan Ruckmani Kandasamy 《International journal of peptide research and therapeutics》2017,23(3):305-311
Stabilisation of protein/peptide drugs against thermal denaturation is a challenging problem, especially for liquid formulations. Various polysaccharides at high concentrations have been reported to improve stability of polypeptides, probably by providing a crowded environment which retards kinetic unfolding and resultant degradation. Levan is a fructose homopolysaccharide which is finding increasing use in pharmaceutical applications, but its use for protein drug stabilization remains meagre. In this study, we used levan for stabilizing a liquid preparation of a peptide antibiotic, bacitracin. We prepared liquid formulations of bacitracin with or without levan and subjected them to storage at 25 °C. The stored samples were then analysed over 120 days for denaturation and antibacterial activity. Differential Scanning Calorimetry, Circular Dichroism and High Performance Liquid Chromatography were used for evaluating the effect of levan on thermal denaturation of bacitracin. We found that levan at 2.5% w/v significantly preserved the antibacterial activity of bacitracin for 120 days as compared to plain buffered bacitracin, even when stored at 25 °C. Also, levan at high concentrations maintained the secondary structure and increased the melting temperature (Tm) of bacitracin in solution. Levan did not form covalent interactions or strong complexation with bacitracin. Based on this study, levan appears as a promising stabilizing agent for preparing liquid formulations of protein/peptide drugs that can be stored at room temperature. 相似文献
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