排序方式: 共有68条查询结果,搜索用时 15 毫秒
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基于Py-GC-MS/MS技术的高寒草原土壤有机质不同组分指纹特征研究 总被引:3,自引:0,他引:3
采用热裂解气相色谱质谱联用(Py-GC-MS/MS)技术来研究高寒草原土壤有机质5个密度组分之间的指纹差异。对150种热解产物进行定性定量分析,并将其根据相似的化学性质分为:烷基类化合物、芳烃及多环芳烃、木质素、酚类物质、多糖、含氮化合物及几丁质。研究结果表明:在高寒草原土壤中,F1(密度为小于1.6g/cm~3)组分主要为植物碎屑,虽然该组份在整体土壤中质量含量较少(0.13%)但其有机质含量相对较高(5.7%),该组份中含有较多的木质素及长链烷基类化合物(主要来源于植物),且随着密度的增加,此类化合物的含量逐渐减少。F2(密度为1.6—1.8g/cm~3)、F3(密度为1.8—2.0g/cm~3)及F4(密度为2.0—2.25g/cm~3)3个组分化学性质相似,其有机化合物的含量在密度组分中呈现增加或减少的过渡状态。F5(密度大于2.25g/cm~3)组分是该土壤的主要组成部分,其质量含量高达98%,该组份中的微生物指纹信息(微生物来源的多糖及含氮化合物)均高于前4个组分。同时,芳烃及多环芳烃这类难降解的物质随着密度的增大逐渐累积,在F5组分中富集。 相似文献
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旨在研究重组融合多肽hEGF-AWRK6(EK)对烫伤模型小鼠感染创面的治疗功效。采用大肠杆菌表达系统表达、纯化融合多肽EK,抑菌实验检测EK抑菌活性;构建小鼠II度烫伤和铜绿假单胞菌感染模型,实验组创面滴注EK(30 mg/L),以PBS、庆大霉素(30 mg/L)、烫伤膏(10 mg/L)为对照,计算烫伤后创面愈合率及菌落数;伤后10 d,取各组小鼠的伤口及周边皮肤进行HE染色及胶原蛋白的Western blotting检测,分析创面病理组织结构。实验结果纯化得到了具有抑菌活性的重组表达融合肽EK;伤后6 d始,EK组小鼠创面菌落数少于对照组,差异极显著(P0.01);EK组小鼠烫伤愈合率显著高于PBS对照组(P0.01);与对照组相比,EK组小鼠创面真皮层细胞排列规则,再上皮化较快,毛囊生长较多,Ⅰ型胶原蛋白表达显著增加。结果表明EK具有抑制小鼠烫伤创面感染、促创面愈合功效,具有开发成为治疗烧伤药物的潜力。 相似文献
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Guilin Li Lifang Zou Wei Xie Shiyao Wen Qiuyu Xie Yun Gao Changshui Xu Hong Xu Shuangmei Liu Shouyu Wang Yun Xue Bing Wu Qiulan Lv Mofeng Ying Xi Zhang Shangdong Liang 《Purinergic signalling》2016,12(3):479-487
Adenosine triphosphate (ATP) participates in signal transmission by acting on P2X receptors, and the P2X7 receptor is involved in the pathophysiological changes of ischemic injury. The PC12 cell line is a popular model system to study sympathetic neuronal function. Long noncoding RNAs (lncRNAs) are highly expressed in the nervous system and serve as regulatory RNAs. In this study, the effects of NONRATT021972 lncRNA siRNA on P2X7-mediated PC12 neuronal injury after exposure to oxygen-glucose deprivation (OGD) were investigated. Our results showed that the viability of PC12 cells cultured with OGD or the P2X7 agonist BzATP was significantly decreased. Treatment with NONRATT021972 siRNA reversed the decreased viability of PC12 cells under OGD conditions. The upregulated P2X7 mRNA and protein levels in PC12 cells under OGD conditions or BzATP treatment were significantly decreased when pretreated with NONRATT021972 siRNA. Moreover, NONRATT021972 siRNA treatment effectively suppressed the increase in [Ca2+]i induced by OGD or P2X7 agonists (ATP or BzATP) in PC12 cells. Therefore, treatment with NONRATT021972 siRNA may decrease sympathetic neuronal injury induced by ischemia. 相似文献
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Lufeng Bai Qiuyu Xie Min Xia Kunjing Gong Na Wang Yuqing Chen Minghui Zhao 《Journal of cellular and molecular medicine》2021,25(9):4316-4325
Uromodulin (UMOD) can bind complement factor H (cFH) and inhibit the activation of complement alternative pathway (AP) by enhancing the cofactor activity of cFH on degeneration of C3b. UMOD, an N-glycans-rich glycoprotein, is expressed in thick ascending limb of Henle's loop where the epithelia need to adapt to gradient change of pH and ion concentration. ELISA-based cofactor activity of cFH and erythrocytes haemolytic assay was used to measure the impact of native and de-glycosylated UMOD on the functions of cFH. The binding assay was performed under different pH and ion concentrations, using ELISA. The levels of sialic acid on UMOD, from healthy controls and patients with chronic kidney disease (CKD), were also detected by lectin-ELISA. It was shown that removal of glycans decreased the binding between UMOD and cFH and abolished the ability of enhancing C3b degradation. In acidic condition, the binding became stronger, but it reduced as sodium concentration increased. A significant decrease of α-2,3 sialic acids on UMOD was observed in CKD patients compared with that of healthy individuals. The sialic acids on UMOD, local pH and sodium concentration could impact the binding capacity between UMOD and cFH and thus regulate the activation of complement AP. 相似文献
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Zou Lifang Tu Guihua Xie Wei Wen Shiyao Xie Qiuyu Liu Shuangmei Li Guilin Gao Yun Xu Hong Wang Shouyu Xue Yun Wu Bing Lv Qiulan Ying Mofeng Zhang Xi Liang Shangdong 《Purinergic signalling》2020,16(3):463-465
Purinergic Signalling - In the original article, Figs. 2, 3b, and 4b were published incorrectly. 相似文献
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丝裂原活化蛋白激酶家族可以在一系列细胞外刺激下调控细胞的行为。作为该家族的四个亚家族之一,p38亚族在许多生理过程中扮演着重要角色。p38信号通路可以在紫外照射、热击、高渗透压、炎症因子、生长因子等细胞外刺激时被激活,调控细胞分化、细胞周期、炎症反应等多种生理过程。文章重点讨论了p38亚族各个成员的特性、该信号通路的组成部分、调控机制以及生物学功能。另外,还分析了p38与其他信号通路的联系以及对一些生理过程的影响。 相似文献
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