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91.
经营管理是企业永恒的主题。企业核心竞争力的提高有待于经营管理机制的创新,企业通过经营管理创新,形成新的动力源,以激发全员的积极性和创造性,为国有建筑施工企业的持续、健康、快速发展提供有力的保障。  相似文献   
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93.
The Sistan Delta in Iran is located at the end of a closed basin with nearly 100% of the supply coming from Afghanistan. This supply is supporting irrigated agriculture in the area and is the source for the lake system around the delta. These Hamoun lakes are ecological very valuable wetlands; a number of them are registered as Ramsar sites. The Iranian government tries to improve the living conditions of the people in the area, among others by providing infrastructure for irrigated agriculture. Further development of the irrigated area will mean less water for the Hamouns with resulting lower average water coverage of the lakes. This will not only endanger the ecosystem that the Hamouns support but also the livelihoods of the people that depend on the goods and services that the lakes provide. This paper describes a study that has been carried out to support decision making on potential development schemes in the delta. The non-availability of data from Afghanistan requires the development of various tools and the use of remote sensing techniques to enable to make estimates for the river flow that Iran can expect from Afghanistan. An IWRM approach has been used for the balancing of interests involved. Some preliminary conclusions are described.  相似文献   
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95.
It is important to estimate the productive efficiencies of industries, especially the fishing industry, in order to determine policies that can improve business conditions. In this study, the productive efficiency of the sandfish coastal gillnet fishery on the east coast of Korea has been estimated using stochastic frontier analysis (SFA). A translog production function wherein the inefficiency was represented by a truncated-normal distribution was established; the output variable was the trip production quantity, the input variables were physical production factors directly related to the fishing activities of vessels, such as tonnage, horsepower, and the number of employed fishers. The average productive efficiency of the sample was 0.59 [0.40–0.79], which implied that productive inefficiency occurs in sandfish coastal gillnet vessels. Moreover, it was verified that there are no differences among the average productive efficiencies of fishing vessels of different tonnages.  相似文献   
96.
Lectin is released from soybean seeds during water uptake. Hemagglutination activity data show that the lectin is a preferential release product within the first 8 hours of hydration. A qualitative filter-paper assay for detection of lectin released by single seeds is used to show that the release phenomenon is independent of seed viability and insensitive to azide.  相似文献   
97.
In the present study, the in vitro and in vivo anti-inflammatory effects of the sulfated polysaccharides isolated from Sargassum fulvellum (SFPS) were evaluated in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and zebrafish. The results indicated that SFPS improved the viability of LPS-stimulated RAW 264.7 macrophages from 80.02 to 86.80, 90.09, and 94.62% at the concentration of 25, 50, and 100 µg/mL, respectively. Also, SFPS remarkably and concentration-dependently decreased the production levels of inflammatory molecules including nitric oxide (NO), tumor necrosis factor-alpha, prostaglandin E2, interleukin-1 beta, and interleukin-6 in LPS-treated RAW 264.7 macrophages. In addition, SFPS significantly inhibited the expression levels of cyclooxygenase-2 and inducible nitric oxide synthase in LPS-treated RAW 264.7 macrophages. Furthermore, the in vivo test results indicated that SFPS improved the survival rate of LPS-treated zebrafish from 53.33 to 56.67, 60.00, and 70.00% at the concentration of 25, 50, and 100 µg/mL, respectively. In addition, SFPS effectively reduced cell death, reactive oxygen species, and NO levels in LPS-stimulated zebrafish. Taken together, these results suggested that SFPS possesses strong in vitro and in vivo anti-inflammatory activities, and could be used as an ingredient to develop anti-inflammatory agents in the functional food and pharmaceutical industries.  相似文献   
98.
The marine is a highly complex ecosystem including various microorganisms. Bacillus species is a predominant microbialflora widely distributed in marine ecosystems. This review aims to provide a systematic summary of the newly reported metabolites produced by marine-derived Bacillus species over recent years covering the literature from 2014 to 2021. It describes the structural diversity and biological activities of the reported compounds. Herein, a total of 87 newly reported metabolites are included in this article, among which 49 compounds originated from marine sediments, indicating that marine sediments are majority sources of productive strains of Bacillus species Therefore, marine-derived Bacillus species are a potentially promising source for the discovery of new metabolites.  相似文献   
99.
本文主要通过工程实例介绍扣件式钢管脚手架在高大跨度梁板模板支撑中的应用,并根据有关规范规定、现场实际情况及现有材料等,结合实践经验对其进行探讨和总结.  相似文献   
100.
Genetic diversity analysis of Acidovorax citrulli in China   总被引:1,自引:0,他引:1  
Acidovorax citrulli has become quite common in China. A collection of 118 strains of A. citrulli was made from throughout China and other countries to determine their genetic relatedness. Strains were identified as A. citrulli by pathogenicity, phenotypic characterization, and PCR. Genetic diversity was determined using pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). PFGE electrophoresis resulted in nine genotypes, which could be typed into two groups based on host; group 1 included strains mainly from melon and group 2 included strains mainly from watermelon. MLST analysis resulted in 73 sequence types (ST) among the 118 A. citrulli strains. All A. citrulli strains were typed into three groups: group 1 with 82 strains (including type strain Fc247), group 2 with 35 strains and group 3 a singleton (Fc380). Similar to PFGE results, group 1 included strains mainly from melon and group 2 included strains mainly from watermelon. The difference was the 10 watermelon strains (pslbtw1-3, 5–11) from Beijing grouped with melon strains of group 1 based on MLST, suggesting that these 10 watermelon strains had a close relationship with melon. Our study indicated that there was genetic differentiation among A. citrulli strains between watermelon and melon. Also, our study was the first attempt to compare PFGE and MLST on analyzing genetic diversity of A. citrulli strains and proved MLST could better distinguish A. citrulli strains.  相似文献   
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