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TNT在大鼠晶状体内的代谢及其对晶状体中抗氧化相关酶活性的影响 总被引:1,自引:0,他引:1
大鼠皮下注射TNT,以HPLC分析其在晶状体内的代谢过程,并检测晶状体谷胱甘肽过氧化物酶、谷胱甘肽还原酶及超氧化物歧化酶的活性变化。发现在注射TNT后2h即可在晶状体内检测到为量极少的TNT及其代谢产物,第12h一氨基二硝基甲苯含量达最高峰。鼠龄较小的大鼠晶状体内TNT及其代谢产物高于鼠龄较大的大鼠.多剂量注射TNT时大鼠晶状体内一氨基二硝基甲苯于第2天达到高峰,TNT于第5天达饱和状态,第18天一氨基二硝基甲苯含量与TNT含量相近。谷胱甘肽过氧化物酶、谷胱甘肽还原酶及超氧化物歧化酶活性在注射TNT的第2天均有不同程度的升高,在第5天和第18天维持在低活性状态。实验表明TNT在晶状体内是通过硝基还原而代谢的.TNT进入晶状体后初期可诱发晶状体抗氧化相关酶活性的增高,后期则导致晶状体抗氧化相关酶活性的降低。 相似文献
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Jin Zhou Zi-Jun Lin Zhong-Hua Cai Yan-Hua Zeng Jian-Ming Zhu Xiao-Peng Du 《Environmental microbiology》2020,22(5):1944-1962
Coral associated microorganisms, especially some opportunistic pathogens can utilize quorum-sensing (QS) signals to affect population structure and host health. However, direct evidence about the link between coral bleaching and dysbiotic microbiomes under QS regulation was lacking. Here, using 11 opportunistic bacteria and their QS products (AHLs, acyl-homoserine-lactones), we exposed Pocillopora damicornis to three different treatments: test groups (A and B: mixture of AHLs-producing bacteria and cocktail of AHLs signals respectively); control groups (C and D: group A and B with furanone added respectively); and a blank control (group E: only seawater) for 21 days. The results showed that remarkable bleaching phenomenon was observed in groups A and B. The operational taxonomic units-sequencing analysis shown that the bacterial network interactions and communities composition were significantly changed, becoming especially enhanced in the relative abundances of Vibrio, Edwardsiella, Enterobacter, Pseudomonas, and Aeromonas. Interestingly, the control groups (C and D) were found to have a limited influence upon host microbial composition and reduced bleaching susceptibility of P. damicornis. These results indicate bleaching's initiation and progression may be caused by opportunistic bacteria of resident microbes in a process under regulation by AHLs. These findings add a new dimension to our understanding of the complexity of bleaching mechanisms from a chemoecological perspective. 相似文献
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Zhang Ting He Mao-Tao Zhang Xiao-Peng Jing Li Zhang Jian-Zhong 《Neurochemical research》2021,46(6):1359-1371
Neurochemical Research - Mitochondrial uncoupling protein 2 (UCP2) deficiency exacerbates brain damage following cerebral ischemia/reperfusion (I/R). The Nod-like receptor protein-3 (NLRP3)... 相似文献
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The statistical thermodynamic (ST) model was used to study nonlinear binary protein adsorption equilibria on an anion exchanger. Single-component and binary protein adsorption isotherms of bovine hemoglobin (Hb) and bovine serum albumin (BSA) on DEAE Spherodex M were determined by batch adsorption experiments in 10 mM Tris-HCl buffer containing a specific NaCl concentration (0.05, 0.10, and 0.15 M) at pH 7.40. The ST model was found to depict the effect of ionic strength on the single-component equilibria well, with model parameters depending on ionic strength. Moreover, the ST model gave acceptable fitting to the binary adsorption data with the fitted single-component model parameters, leading to the estimation of the binary ST model parameter. The effects of ionic strength on the model parameters are reasonably interpreted by the electrostatic and thermodynamic theories. The effective charge of protein in adsorption phase can be separately calculated from the two categories of the model parameters, and the values obtained from the two methods are consistent. The results demonstrate the utility of the ST model for describing nonlinear binary protein adsorption equilibria. 相似文献
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Wang Xiao-Peng Ye Pin Lv Jiao Zhou Lei Qian Zhong-Yi Huang Yong-Jie Mu Zhi-Hao Wang Xie Liu Xin-jie Wan Qi Yang Zhi-Hong Wang Fang Zou Ying-Ying 《Neurochemical research》2019,44(4):978-993
Neurochemical Research - Cognitive impairment in diabetes (CID) is a severe chronic complication of diabetes mellitus (DM). It has been hypothesized that diabetes can lead to cognitive dysfunction... 相似文献
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反相高效液相色谱法测定血清中γ-氨基丁酸 总被引:8,自引:0,他引:8
建立一种高灵敏度的氯甲酸芴甲酯柱前衍生荧光检测反相高效液相色谱法测定血清中γ-氨基丁酸的方法.内标为己氨酸, 固定相为Shim-Pack CLC-ODS(M), 4.6 mm×150 mm, 填充料为5μm; 流动相采用二元梯度洗脱, A相为0.05 mol/L醋酸钠缓冲液∶水∶四氢呋喃∶冰乙酸(250∶100∶15∶2.2), B相为乙腈∶甲醇(4∶1).系统研究了pH值、反应时间、离子强度及衍生化试剂用量对衍生化反应的影响, 确定最佳反应条件和最佳色谱条件.方法的精密度为批内变异系数<4.6%,批间变异系数<6.1%;最低检出限(信噪比=2)为3.1 nmol/L;线性范围为50~1000 nmol/L, γ2=0.9992;平均回收率为97.1%. 相似文献
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Xiao-Peng Song Chengquan Huang Sassan S. Saatchi Matthew C. Hansen John R. Townshend 《PloS one》2015,10(5)
Reducing emissions from deforestation and forest degradation (REDD+) is considered one of the most cost-effective strategies for mitigating climate change. However, historical deforestation and emission rates―critical inputs for setting reference emission levels for REDD+―are poorly understood. Here we use multi-source, time-series satellite data to quantify carbon emissions from deforestation in the Amazon basin on a year-to-year basis between 2000 and 2010. We first derive annual deforestation indicators by using the Moderate Resolution Imaging Spectroradiometer Vegetation Continuous Fields (MODIS VCF) product. MODIS indicators are calibrated by using a large sample of Landsat data to generate accurate deforestation rates, which are subsequently combined with a spatially explicit biomass dataset to calculate committed annual carbon emissions. Across the study area, the average deforestation and associated carbon emissions were estimated to be 1.59 ± 0.25 M ha•yr−1 and 0.18 ± 0.07 Pg C•yr−1 respectively, with substantially different trends and inter-annual variability in different regions. Deforestation in the Brazilian Amazon increased between 2001 and 2004 and declined substantially afterwards, whereas deforestation in the Bolivian Amazon, the Colombian Amazon, and the Peruvian Amazon increased over the study period. The average carbon density of lost forests after 2005 was 130 Mg C•ha−1, ~11% lower than the average carbon density of remaining forests in year 2010 (144 Mg C•ha−1). Moreover, the average carbon density of cleared forests increased at a rate of 7 Mg C•ha−1•yr−1 from 2005 to 2010, suggesting that deforestation has been progressively encroaching into high-biomass lands in the Amazon basin. Spatially explicit, annual deforestation and emission estimates like the ones derived in this study are useful for setting baselines for REDD+ and other emission mitigation programs, and for evaluating the performance of such efforts. 相似文献
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Fei Wang Shu Li Xin-Wen Bai Xiao-Peng Ren Li-Lin Rao Jin-Zhen Li Huan Liu Hong-Zhi Liu Bin Wu Rui Zheng 《PloS one》2015,10(5)
Understanding urbanization and evaluating its impact are vital for formulating global sustainable development. The results obtained from evaluating the impact of urbanization, however, depend on the kind of measurement used. With the goal of increasing our understanding of the impact of urbanization, we developed direct and indirect subjective indicators to measure how people assess their living situation. The survey revealed that the projected endorsements and perceived social ambiance of people toward living in different types of settlements did not improve along with the urbanization level in China. The assessment scores from the city dwellers were not significantly different from those from the country areas and, more surprisingly, both were significantly higher than the assessment scores of the town dwellers, which we had expected to fall between the assessment scores of the country and city dwellers. Instead their scores were the lowest. We dubbed this V-shaped relationship the “town dislocation effect.” When searching for a potential explanation for this effect, we found additional town dislocation effects in social support, loss aversion, and receptivity toward genetically modified food. Further analysis showed that only social support mediated the relationship between the three tiers of settlements (cities, country areas, and towns) and the subjective indicator. The projected endorsements yielded significant subjective assessments that could enhance our understanding of Chinese urbanization. Towns posed specific problems that require special attention. 相似文献