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排序方式: 共有290条查询结果,搜索用时 15 毫秒
91.
TAN Xiao-fan CHEN Yuan-han YU Chun-ping LAI Yu-xiong ZHANG Li ZHAO Xing-chen ZHANG Hong LIN Ting LI Rui-zhao SHI Wei 《园艺学报》2014,30(12):2232-2237
AIM: To investigate the influence of advanced glycosylation end products-modified bovine serum albumin (AGE-BSA) on mammalian target of rapamycin complex 1 (mTORC1), urokinase-type plasminogen activator receptor (uPAR), and cell mobility in the podocytes, and to further explore the probable relationship. METHODS: The conditionally immortalized mouse podocyte cell line was cultured in vitro. MTT assay and immunofluorescence were used to analyze the cell viability and cytoskeleton of the podocytes treated with the stimuli and intervention agents. The activity of mTORC1 and the expression level of uPAR in normal podocytes and podocytes treated with control BSA or AGE-BSA were detected by Western blotting. The migration ability of the podocytes was determined by would-healing assay. Rapamycin was added to inhibit the activity of mTORC1 along with the addition of AGE-BSA to observe the changes of uPAR and the motility of podocytes. RESULTS: No significant difference of the cell viability or cytoskeleton in the podocytes treated with the stimuli and intervention agents was observed. AGE-BSA up-regulated the activity of mTORC1 and the expression of uPAR, and induced the high mobility of the podocytes. Rapamycin obviously reduced the high expression level of uPAR and the increase in the migration ability of podocytes caused by AGE-BSA treatment. CONCLUSION: AGE-BSA might cause the high migration of podocytes through the mTORC1/uPAR signaling pathway. 相似文献
92.
《African Journal of Range and Forage Science》2013,30(1-2):85-89
Pastoralists in Namaqualand, South Africa, use herd mobility to manage livestock and rangeland resources. However, their socioeconomic conditions and ecological landscapes are changing and we explore the options that are available for pastoralists to respond to these changes. This paper presents five possible scenarios for managing livestock in rangeland commons in semi-arid Namaqualand and outlines some of the major advantages and disadvantages associated with each scenario. Scenarios in response to drivers of change include (1) maintaining the status quo with an assumption that current mobility practices are adapted to local environments, (2) integrating new lands into the existing commons for use by mobile pastoralists, (3) using existing lands under existing mobile pastoralism conditions but introducing grazing reserves for use in times of drought, (4) amalgamating herds into larger units under the care of skilled herders, and (5) developing commercial-scale farms for single-occupancy owners because government might be pressured to further promote black commercial farmers to deracialise the commercial farming sector in South Africa. We consider these scenarios as starting points for discussions on future management options that pastoralists in Namaqualand may wish to consider as the managers of rangeland commons. 相似文献
93.
94.
AIM: To investigate the role of epidermal growth factor receptor (EGFR)-p38 mitogen-activated protein kinase (MAPK) pathway in the expression of high mobility group box 1 protein (HMGB1) in the lung tissues of rats with ventilator-induced lung injury (VILI).METHODS: Thirty-two healthy Sprague-Dawley (SD) rats were randomly divided into 4 groups (n=8 each): group A, spontaneous breathing; group B, small tidal volume ventilation (VT=8 mL/kg); group C, high tidal volume ventilation (VT=40 mL/kg); group D, high tidal volume ventilation plus EGFR antagonist AG-1478. The rats in group B, group C and group D were mechanically ventilated for 4 h and then all animals were sacrificed.Total protein content and white blood cell (WBC) count in bronchoalveolar lavage fluid (BALF), the lung wet/dry weight ratio (W/D) and myeloperoxidase (MPO) activity were determined. The histological changes of lung tissues were observed by HE staining. The EGFR protein and mRNA expression, p38 MAPK activity and HMGB1 protein expression in the lung tissues were also detected.RESULTS: The inflammatory responses as evidenced by lung HE staining, total protein and WBC in BALF, the lung W/D and MPO activity were significantly higher in group C than those in group A (P<0.05). The mRNA expression of EGFR, EGFR activity, p38 activity and HMGB1 protein level also significantly increased in group C (P<0.05) as compared with group A. Significant decreases in the above indexes in group D were observed as compared with group C.CONCLUSION: High tidal volume ventilation induces acute lung injury, which may be related to up-regulation of HMGB1 expression through EGFR-p38 MAPK signal pathway. 相似文献
95.
《Communications in Soil Science and Plant Analysis》2012,43(18):2131-2142
A screen-house experiment was conducted to study cadmium (Cd) and lead (Pb) phytoextraction using mustard and fenugreek as test crops. Cadmium was applied at a rate of 20 mg kg?1 soil for both crops, and Pb was applied at 160 and 80 mg kg?1 soil for mustard and fenugreek, respectively. The disodium salt of ethylenediamine tetraacetic acid (EDTA) was applied at 0, 0.5, 1.0, and 1.5 g kg?1 soil. Dry-matter yield (DMY) of both crops decreased with increasing rates of EDTA application. Application of 1.5 g EDTA kg?1 soil caused 23% and 70% declines in DMY of mustard and fenugreek shoots, respectively, in the soils receiving 20 mg Cd kg?1 soil. Similarly, in soil with 160 mg Pb kg?1 soil, application of 1.5 g EDTA kg?1 resulted in 25.4% decrease in DMY of mustard shoot, whereas this decrease was 55.4% in fenugreek grown on a soil that had received 80 mg Pb kg?1 soil. The EDTA application increased the plant Cd and Pb concentrations as well as shoot/root ratios of these metals in both the crops. Application of 1.5 g kg?1 EDTA resulted in a 1.50-fold increase in Cd accumulation and a 3-fold increase in Pb accumulation by mustard compared to the control treatment. EDTA application caused mobilization of Cd and Pb from carbonate, manganese oxide, and amorphous iron oxide fractions, which was evident from decrease in these fractions in the presence of EDTA as compared to the control treatment (no EDTA). 相似文献
96.
《Journal Of Aquatic Food Product Technology》2013,22(3-4):21-29
Abstract The freshness of vendace (Coregonus albulaL.) caught in Finland either in August or in April was followed over the storage period of 7 days. Microbiological analyses, measurement of volatile compounds using ion mobility based gas detector and measurements of electrical properties (Torrymeter score values) of fish were used to estimate the freshness of vendace. In the low environmental temperatures, the number of fish-associated bacteria was lower than during the summer season. This could be seen in 1-2 days longer shelf life of the catch, the maximum shelf life of vendace being approximately 6-7 days for winter fish and 5-6 days for summer fish. The differences in the amount of proteolytic and lipolytic bacteria may affect the degradation process during the storage of fish. 相似文献
97.
Guedes RN Campbell JF Arthur FH Opit GP Zhu KY Throne JE 《Pest management science》2008,64(12):1314-1322
BACKGROUND: The psocids Liposcelis bostrychophila Badonnel and L. entomophila (Enderlein) (Liposcelididae) are emerging pests of stored products. Although their behavior, particularly their high mobility, may contribute to the reported relatively low efficacy of insecticides against them, studies to investigate this have not been conducted. The present study aimed to assess the label rate efficacy of three commercial insecticides (β‐cyfluthrin, chlorfenapyr and pyrethrins) applied on concrete surfaces against L. bostrychophila and L. entomophila, and also their sublethal effect on the mobility of these species. RESULTS: The synthetic insecticides β‐cyfluthrin and chlorfenapyr showed high short‐term efficacy (LT95≤15 h) against both psocid species, unlike the natural pyrethrins (LT95 ≥ 4 days). Liposcelis bostrychophila was slightly more tolerant (≥1.2×) than L. entomophila to all three insecticides. Behavioral assays with fully sprayed and half‐sprayed concrete arenas indicated that the insecticides reduced the mobility of both species. Pyrethrins seem to elicit weak repellence in L. bostrychophila. CONCLUSION: β‐Cyfluthrin and chlorfenapyr were effective against both psocid species, but not pyrethrins. The mobility of both species does not seem to play a major role in the differential selectivity observed, but the lower mobility of L. bostrychophila may be a contributing factor to its higher insecticide tolerance. Published in 2008 by John Wiley & Sons, Ltd. 相似文献
98.
Ali Sungur 《Archives of Agronomy and Soil Science》2016,62(8):1051-1065
The aim of the study was determine potential mobility, sources, and environmental impacts of heavy metals in soil of urban apple orchards using a sequential extraction procedure and multivariate analysis. The soil and apple (Malus domestica Borkh.) leaf samples were collected from apple orchards of urban areas in Çanakkale, Turkey. A sequential extraction procedure was employed to determine the binding forms of Cd, Cr, Cu, Ni, Pb, and Zn in soil samples. Sequential extraction procedure revealed that mobile fractions (acid soluble, reducible, and oxidizable) of Cd (60.2%) and Pb (56.8%) were higher than their immobile fractions. Such higher mobile fractions indicate the anthropogenic sources, and multivariate analysis results also supported the existence of such sources. The relationship between pH and mobile fractions of the metals (sum of acid soluble, reducible, and oxidizable) indicates that Cd and Pb become more mobile under decreasing pH conditions. Considering all metals, except for Cd, a strong relationship was observed between metal concentrations of apple leaves and mobile fractions, and plants were primarily able to uptake the metals in these fractions. Contamination factor and risk assessment code results together also revealed that Cd was highly mobile; retained less and had high risk for the environment. 相似文献
99.
Shimaa M. Abou-Zeid Samira H. Aljuaydi Huda O. AbuBakr Enas A. Tahoun Alessandro Di Cerbo Mahmoud Alagawany Samah R. Khalil Mayada R. Farag 《Marine drugs》2021,19(9)
Thiacloprid (TCP) is a widely used neonicotinoid insecticide with a probable toxic hazard to animals and human beings. This hazard has intensified the demand for natural compounds to alleviate the expected toxic insults. This study aimed at determining whether astaxanthin (ASX) could mitigate the hepatotoxic effect of TCP and diminish its suppressive effect on immune responses in rats. Animals received TCP by gavage at 62.1 mg/kg (1/10th LD50) with or without ASX at 40 mg/kg for 60 days. Intoxicated rats showed modulation of serum transaminases and protein profiles. The hemagglutination antibody titer to sheep red blood cells (SRBC) and the number of plaque-forming cells in the spleen were reduced. The cell-mediated immunity and phagocytosis were suppressed, while serum interleukins IL-1β, IL-6, and IL-10 were elevated. Additionally, malondialdehyde, nitric oxide, and 8-hydroxy-2′-deoxyguanosine levels were increased in the liver, spleen, and thymus, with depletion of glutathione and suppression of superoxide dismutase and catalase activities. The expressions of inducible nitric oxide synthase and the high mobility group box protein 1 genes were upregulated with histomorphological alterations in the aforementioned organs. Cotreatment with ASX markedly ameliorated the toxic effects of TCP, and all markers showed a regression trend towards control values. Collectively, our data suggest that the protective effects of ASX on the liver and immune system of TCP-treated animals depend upon improving the antioxidant status and relieving the inflammatory response, and thus it may be used as a promising therapeutic agent to provide superior hepato- and immunoprotection. 相似文献
100.
提出了一种新型四分支并联机构。采用李群理论对机构进行了自由度分析,该机构能输出两转动两移动运动,可由与机架相邻的移动副驱动。研究了机构的位置模型,推导得到了位置反解和正解的表达式,分析了机构的运动部分解耦特性。求解了机构的雅可比矩阵,基于雅可比矩阵行列式讨论了其奇异位形。绘制了机构的工作空间及内部奇异分布,机构的奇异分布在工作空间边缘,具有很大的转动能力。机构在中间位置两个方向的转角范围分别可达-44°~60°和-35°~52°。对机构进行了运动/力传递性能分析,得到了工作空间内的性能分布情况,以全域传递指标为目标对机构进行了尺度优化。 相似文献