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141.
Vascular complications are major causes of graft failure in liver transplantation. The use of different vascular grafts is common but the results are controversial. The aim of this study was to create an 'ideal' arterial interponate for vascular replacements in the clinical field. An autologous, tubular graft prepared from the posterior rectus fascia sheath was used for iliac artery replacement in dogs for 1, 3, 6 and 12 months. Forty-one grafts were implanted and immunosuppression was used in separate groups. The patency rate was followed by Doppler ultrasound. Thirty-seven grafts remained patent, 2 cases with thrombosis and 2 cases with stenosis occurred. There was no evidence of necrosis or aneurysmatic formation. The histological analysis included conventional light microscopic and immunohistochemical examinations for CD34 and factor VIII. The explanted grafts showed signs of arterialisation, appearance of elastin fibres, and smooth muscle cells after 6 months. Electron microscopy showed intact mitochondrial structures without signs of hypoxia. In conclusion, the autologous graft presents acceptable long-term patency rate. It is easy to handle and the concept of beneficial presence of the anti-clot mesothelium until endothelialisation seems to work. The first clinical use was already reported by our group with more than 2 years survival.  相似文献   
142.
Foliar sprayings of grapevines with different plant growth regulators or chemicals were evaluated for determining grape skin color and phenolic compounds content and enhancing table grape quality characteristics of cv. Red Globe in this study. Grape skin color is one of the most important quality factors for table grapes. Sometimes, it can be viewed difficulties in skin coloration of some red table grape cultivars grown in various grape growing regions of the world and poor skin coloration of red table grapes is a frequent trouble that reduces production efficiency. Despite the fact that it is utilized from some canopy management practices; plant growth regulators, chemicals with plant hormones and hormone-like compounds as active ingredients can be recently used for improving anthocyanin accumulation in growing of some table grape cultivars. In current study, nine different preharvest treatments were used for improving quality parameters of cv. Red Globe, including 1?Control (C), 2–300?mg/L Abscisic acid (ABA), 3–300?mg/L Ethephon (Eth), 4–30% Ethanol (EtOH), 5–300?mg/L ABA + 300?mg/L Eth, 6–300?mg/L ABA + 30% EtOH, 7–300?mg/L Eth + 30% EtOH, 8–300?mg/L ABA + 300?mg/L Eth + 30% EtOH and 9?Cluster tip cutting (CTC). Although the best results from total phenolic compounds content and total anthocyanin content of cv. Red Globe were obtained in CTC treatment in all preharvest treatments, Eth+ETOH treatment especially gave rise to the best results among the preharvest chemical treatments.  相似文献   
143.
Abstract

A field study with maize (Zea mays L.) was conducted in the 1988/89 cropping season to investigate the fate of 15NO3-N-labelled NH4 15NO3 applied at 40, 80 and 120 kg N ha?1 (unlabelled N applied at 0, 80, 160 and 240 N ha?1) with and without lime. The investigations were conducted in northern Zambia at Misamfu Regional Research Centre, Kasama on a Misamfu red sandy loam soil. The experimental design was a split plot arrangement with four replications with main plots receiving 0 and 2 Mg ha?1 dolomitic limestone, while subplots received fertilizer N at various rates. Significant (p < 0.001) grain and DM yield responses to applied N up to 160 kg ha?1 were observed. At higher rates little or no crop responses were observed and fertilizer use efficiency declined. Partitioning of amounts of total N and 15N in plants was in the order of seed = tassel > leaf> cob = earleaf> stem. Fertilizer N rates showed a highly significant (p < 0.001) effect on plant uptake of labelled N. Lime and its interaction with N rates had no effect on all measured parameters. Leaching of NO3-N fertilizer to lower soil depths was in proportion to the rate of N applied, with highly significant (p < 0.001) differences among soil depths. Although higher concentrations of fertilizer-15N were recovered in the 0–20 cm depth the recovered portion at lower soil depths was still significant. Total recovery of labelled N by plant and by soil after crop harvest averaged 75, 55 and 54% of originally applied fertilizer-15N at 40, 80 and 120 kg N ha?1, respectively. Corresponding unaccounted for 15N was 25, 45 and 46%. The most probable loss mechanism could have been by leaching to depths greater than 60 cm, gaseous losses to the atmosphere and root assimilation.  相似文献   
144.
In 1998, we analysed regeneration success in four 20 year old medium-sized (600–800 m2) and four small experimental gaps (100–200 m2) in subalpine Norway spruce forest in Triglav National Park, Slovenia. We assessed the influence of site (depressions, slopes), gap size, and position within gap (centre, gap south, and north edge) on regeneration success and interactions between regeneration density, height, height increment, direct and diffuse light, ground vegetation, soil depth, thickness of humus horizons, presence of woody debris, and microrelief. Seedling density was higher in depressions, where more seedlings developed in central positions of gaps in both gap sizes, and in microsites with deeper soils, less competition from ground vegetation and convex microsites. On slopes, a higher seedling density was found in small gaps, and at the northern edge of gaps regardless of gap size. Here, seedling density was negatively influenced by diffuse radiation and positively by soil depth. The results suggest that regeneration should be initiated from medium to large gaps in depressions and small gaps on slopes. Development of established seedlings was enhanced by higher radiation levels on both sites, therefore favourable extension of the gaps would be lateral to northwards.  相似文献   
145.
Pandey  R. A.  Malhotra  S.  Rajvaidya  A. S.  Sharma  S.  Peshwe  S.  Raman  V. K.  Bal  A. S. 《Water, air, and soil pollution》2003,142(1-4):243-260
Gases and suspended particulate matter are sampled and measured in situ at different sites within the city of Madrid to determinethe air pollution in the city. Lead concentrations in air are also determined. The information needed to assess levels of contaminants is obtained combining several analytical techniques,which provide real time concentration data of particles andgases. Particulate matter (PM), SO2, CO, O3, NOx,NO2, CH4, total hydrocarbons and Pb were measured. Concentrations of pollutants are averaged over periods of hours,days, months and years. Variations of contaminant concentrationsin the last years are presented. Spatial and temporal distribution follows that of the traffic, the main source of pollution in Madrid City. Some specific measurements were carriedout to understand the influence of traffic emissions at themeasured site. Further, all measured concentrations never exceeded the European Union Directives.  相似文献   
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Utilization from bio fertilization is well known a considerable tool to improve the yield and fruit quality of various crop fruits through the increasing emphasis on maintain of soil health, minimize environmental pollution and decrease the use of chemical fertilization. In this study, in order to improve wine grape quality features of cv. Shiraz, four different doses of foliar microbial fertilizer, including 0, 1000, 2000 and 3000?ppm were applied at two different terms as Term I (mostly; pre-bloom applications) and Term II (mostly; post-bloom applications). However, there were no influences of application terms of foliar microbial fertilizer treatments; treatment doses had considerable effects on yield and quality parameters. The lowest p-values, meaning the highest berry quality, from doses of foliar microbial fertilizer were obtained from 2000?ppm (105.08?μW), 1000?ppm (110.40?μW), 3000?ppm (112.97?μW) and 0?ppm (119.58?μW). Comparing the applications of foliar microbial fertilizer, it was observed that doses of 2000?ppm (3155.56?mg/kg), 1000?ppm (3000.92?mg/kg) and 3000?ppm (2530.19?mg/kg) exhibited higher total phenolic compounds content when compared with 0?ppm treatment (2206.97?mg/kg). Berries from grapevines applied with the doses of 2000, 1000 and 3000?ppm foliar microbial fertilizer respectively shown higher total anthocyanin content such as 1230.19, 1160.85 and 865.86?mg/kg compared to 0?ppm (637.37?mg/kg). As a result, research the findings indicated that 2000 and 1000?ppm doses of foliar microbial fertilizer were obviously effective on wine grape quality features of cv. Shiraz in terms of electrochemical property, total phenolic compounds content and total anthocyanin content.  相似文献   
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