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Two cultivars of Jerusalem artichoke (Helianthus tuberosus L.) differing in genotype, Red skin (cv. R., salt-tolerant but low-yield) and White skin (cv. W., salt-sensitive but high-yield), were used to investigate malondialdehyde (MDA) content and antioxidant enzyme activity changes in their roots under a hydroponic culture system with 250 mM NaCl. The results showed that MDA contents in roots of the two genotypes increased, but MDA content of cv. R. was higher than that of cv. W. Changes in all antioxidant enzymes in roots of both varieties exhibited a similar trend, namely increased initially and then decreased. However, there were still some differences existing between the two cultivars. In other words, activities of the other two antioxidant enzymes except catalase (CAT) and peroxidase (POD) in roots of cv. R. were less than controls at 48 h, while all others except ascorbate peroxidase (APX) in roots of cv. W. were greater than controls. The peak of superoxide dismutase (SOD) activity of cv. W. was observed to appear earlier than that of cv. R. CAT activity of cv. W. was significantly greater than the value of cv. R. and the latter showed a moderate trend. POD activity of cv. R. obtained the maximum at 6 h, whereas the peak of cv. W. displayed at 24 h. APX activity of cv. R. declined more than that of cv. W. These results suggested that there was a lower efficiency of scavenging reactive oxygen species (ROS) in cv. R. roots. Concomitantly, salt stress caused more severe damage to roots of cv. R. Antioxidant enzymes in roots were inadequate to elucidate salt-tolerance mechanisms of the whole plant.
A Pressure-State-Response (PSR) framework was developed to realize a holistic health assessment of the Ulansuhai Lake in the Inner Mongolia. A total of 25 indicators including ecological character indicators, ecological function indicators and social environment indicators were organized to assess the lake ecosystem health. The Ulansuhai Lake was regionalized into three sub-regions (I, II, and III) in the consideration of ecological and environmental characters the lake. Results indicate the lake is in the state of Alert or Worse. The comprehensive health indices (CHI) of three sub-regions are 0.346, 0.385, and 0.445, respectively, reflecting obvious regional differences in ecosystem health of the lake. The current study may provide useful information for valid wetland restoration and management
Physiological responses of two Jerusalem artichoke (Helianthus tuberosus L.) cultivars with different drought sensitivity to drought stress induced by polyethylene glycol (PEG) 6000 were investigated by characterizing water status, membrane lipid peroxidation, key antioxidant enzymes activity, and proline accumulation. It was observed that the drought-tolerant Jerusalem artichoke cv. Xiuyan maintained a relatively higher water status than the drought-sensitive cv. Yulin upon drought treatments. Meanwhile, lower levels of malondialdehyde (MDA) as well as higher levels of free proline occurred in cv. Xiuyan after 36 h drought treatments. Moreover, the activities of catalase (CAT) and superoxide dismutase (SOD) in cv. Xiuyan were higher than cv. Yulin after drought stress. These results indicated that drought sensitivities actually differ between Jerusalem artichoke cv. Xiuyan and cv. Yulin, and the cv. Xiuyan was more tolerant to drought stress caused by polyethylene glycol.
An increasing interest is focused on somatic embryogenesis induction in plants. This process usually generates both embryogenic calli (EC) and non-embryogenic calli (NEC) from the same explant. To identify specific proteins involved in embryogenesis competence, a comparative proteomics of EC and NEC in Liriodendron hybrid was performed. Proteins of EC and NEC were separated by two-dimensional gel electrophoresis (2-DE) and 14 proteins specific embryogenesis were characterized by matrix-assisted laser desorption ionization time-of-flight/- time-of-flight. Among these identifying proteins, profilin may be indispensable for cell survival and division, and eIF- 5A may play a functional role in embryogenic competence and further embryo development. Regulation of programmed cell death by cathepsin b-like cysteine proteinase and proteasome 20S beta1.1 subunit may have an essential part in maintaining cellular pluripotency and reprogramming for embryogenic mass. Reactive oxygen species (ROS) have a central effect on triggering cell division. However, methionine sulfoxide reductase is probably involved in protecting the cell from damage from excessive reactive oxygen species. Expression of EF-hand family proteins in embryogenic calli may mediate the calcium ion gradient for polarization and organ patterning. These identified embryogenic calli-specific proteins provide clues to understanding low conversion rate from calli cells to embryogenic cells.
The ship’s pilot can obtain the ship auxiliary information through the navigation system, when berthing system can display the parameters such as traverse speed and distance of the ship. But most of the system data show that there are insufficient precision. Taking the CORS system to obtain the location information, data Calculation of Berthing System based on Polar Coordinate Algorithm, this paper puts forward a solution to the “dead point” of the berthing and aiding system, which has a certain reference value for the design of the ship berthing assistance system
In this paper, a numerical code for predicting the hydrodynamic performance of vertical-axis tidal turbine array is developed. The effect of the tip speed ratio, solidity, and preset angle on the hydrodynamic performance are discussed using a series of calculations. The load principle of the rotor and the variation principle of the turbine power coefficient are studied. All these results can be considered as a reference for the design of vertical-axis tidal turbines
S100A4 is a member of the S100 family of calcium-binding proteins that is directly involved in tumor metastasis. In the present study, we examined the potential role of S100A4 in metastasis in breast cancer and its relation with matrix metalloproteinase-13 (MMP-13). Analysis of 100 breast cancer specimens including 50 with and 50 without lymph node metastasis showed a significant upregulation of S100A4 and MMP-13 expression in metastatic breast cancer tissues. Positive immunoreactivity for S100A4 was associated with MMP-13 expression. Overexpression of S100A4 in the MDA-MB-231 breast cancer cell line upregulated MMP13 expression leading to increased cell migration and angiogenesis. SiRNA-mediated silencing of S100A4 downregulated MMP13 expression and suppressed cell migration and angiogenesis. Moreover, neutralization of MMP-13 activity with a specific antibody blocked cell migration and angiogenesis in MDA-MB-231/S100A4 cells. In vivo siRNA silencing of S100A4 significantly inhibited lung metastasis in transgenic mice. The present results suggest that the S100A4 gene may control the invasive potential of human breast cancer cells by modulating MMP-13 levels, thus regulating metastasis and angiogenesis in breast tumors. S100A4 could therefore be of value as a biomarker of breast cancer progression and a novel therapeutic target for human breast cancer treatment.
Agaricus bisporus plays an important role in ecological processes and is one of the most widely cultivated mushrooms worldwide. Mushroom growth-promoting bacteria have been isolated from casing soil and compost, but microorganisms in the fruiting body have received only a little attention. To get an overview of phylogenetic diversity of microorganisms in the fruiting body of A. bisporus, as well as to screen antimicrobial and mushroom growth-promoting strains, and eventually intensify mushroom production, we isolated and characterized microorganisms from the fruiting body of A. bisporus. In total, 55 bacterial strains were isolated, among which nine isolates represented Actinomycetes. All the isolates were analyzed by 16S rRNA gene RFLP and sixteen representative strains by 16S rRNA gene sequencing. According to the phylogenetic analysis, eleven isolates represented the Gram-positive Bacillus, Lysinibacillus, Paenibacillus, Pandorea and Streptomyces genera, and five isolates belonged to the Gram-negative Alcaligenes and Pseudomonas genera. The bacteria isolated from the fruiting body of A. bisporus had broad-spectrum antimicrobial activities and potential mushroom growth-promoting abilities.
Over the last 5 decades, runoff from the upstream area of the Yongding River basin has greatly decreased because of changes in the climate and in the intensity of human activities. The Mann-Kendall rank correlation trend test, cumulative anomaly method, and double mass curve of precipitation and runoff were applied to analyse the hydrological sequence trends and altered features in the upstream area of the Yongding River during 1960-2010. The influences of climate change and human activities on changes in runoff were quantitatively assessed using a climate elasticity method based on the Budyko hypothesis. In this paper, the results showed that, on average, runoff in the 3 basins in the upstream area of the Yongding showed a significant (99% confidence level) downward trend. We found that human activities were the main driving factors for the decline in annual runoff in the Yanghe River basin, Sanggan River basin, and upstream area of the Yongding River basin, accounting for 82.04%, 81.51%, and 75.69% of the runoff reduction, respectively, during evaluation period I, and accounting for 77.94%, 72.73%, and 73.37% of runoff reduction, respectively, during evaluation period II. However, the impact of climate variability on runoff gradually increased over time in the 3 basins.
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