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171.
The progress of aqueous zinc batteries (AZBs) is limited by the poor cycling life due to Zn anode instability, including dendrite growth, surface corrosion, and passivation. Inspired by the anti-corrosion strategy of steel industry, a compounding corrosion inhibitor (CCI) is employed as the electrolyte additive for Zn metal anode protection. It is shown that CCI can spontaneously generate a uniform and ≈30 nm thick solid-electrolyte interphase (SEI) layer on Zn anode with a strong adhesion via Zn O bonding. This SEI layer efficiently prohibits water corrosion and guides homogeneous Zn deposition without obvious dendrite formation. This enables reversible Zn deposition and dissolution for over 1100 h under the condition of 1 mA cm−2 and 1 mAh cm−2 in symmetric cells. The Zn-MnO2 full cells with CCI-modified electrolyte deliver an ultralow capacity decay rate (0.013% per cycle) at 0.5 A g−1 over 1000 cycles. Such an innovative strategy paves a low-cost way to achieve AZBs with long lifespan.  相似文献   
172.
Hu  Xiaoyu  Tang  Ruibo  Zhao  Caijun  Mu  Ruiying  Wang  Ying  Cao  Yongguo  Zhang  Naisheng  Fu  Yunhe 《Probiotics and antimicrobial proteins》2023,15(1):74-81
Probiotics and Antimicrobial Proteins - Mastitis, common inflammation of the mammary gland, caused by various factors, is a challenge for the dairy industry. Escherichia coli (E. coli), a...  相似文献   
173.
The obligate biotrophic fungus Puccinia striiformis f. sp. tritici (Pst) employs virulence effectors to disturb host immunity and causes devastating stripe rust disease. However, our understanding of how Pst effectors regulate host defense responses remains limited. In this study, we determined that the Pst effector Hasp98, which is highly expressed in Pst haustoria, inhibits plant immune responses triggered by flg22 or nonpathogenic bacteria. Overexpression of Hasp98 in wheat (Triticum aestivum) suppressed avirulent Pst-triggered immunity, leading to decreased H2O2 accumulation and promoting P. striiformis infection, whereas stable silencing of Hasp98 impaired P. striiformis pathogenicity. Hasp98 interacts with the wheat mitogen-activated protein kinase TaMAPK4, a positive regulator of plant resistance to stripe rust. The conserved TEY motif of TaMAPK4 is important for its kinase activity, which is required for the resistance function. We demonstrate that Hasp98 inhibits the kinase activity of TaMAPK4 and that the stable silencing of TaMAPK4 compromises wheat resistance against P. striiformis. These results suggest that Hasp98 acts as a virulence effector to interfere with the MAPK signaling pathway in wheat, thereby promoting P. striiformis infection.  相似文献   
174.
Abstract The extracts from 7 species of bamboo were tested for larvicidal activity against Culex pipiens pallens . At the tested concentration, the extracts of selected bamboo had different degree of toxic effects on the fourth instar larvae of Culex pipiens pallens . Among them, the extracts of Pleioblastus juxianensis, Brachystachyum albostriatum, Phyllostachys platyglossa and Pleioblastus amarus were found to be effective with LC50values at 24 h of 30.65 mg/L, 53.94 mg/L, 41.21 mg/L and 54.49 mg/L respectively, against Culex pipiens pallens larvae. The extract of Pleioblastus juxianensis by Soxhlet method showed stronger activity than the extract obtained by interval-shaking, the LC50 of which were 30.65 mg/L and 48.34 mg/L, respectively. The diethyl ether extract of Pleioblastus juxianensis exhibited better larvicidal activity than the methanol extract and the petroleum ether extract. The results would help to provide the basis for the study of environment acceptable pesticide for mosquito control, and also help to comprehensively utilize the source of bamboo.  相似文献   
175.
A series of plasmids were constructed to examine the effects of p19 and orf1‐orf2 genes from Bacillus thuringiensis on Cyt1Aa synthesis and inclusion formation. The plasmids expressed the cyt1Aa gene along with either p19 or orf1‐orf2, or each of them coordinatively with p20 in the acrystalliferous strain of B. thuringiensis subsp. israelensis 4Q7. No effect on the expression of Cyt1Aa protein was found when P19 or Orf1‐Orf2 co‐expressed with Cyt1Aa. However, when including p20 gene, the constructs with p19 or orf1‐orf2 gene produced lower yield of Cyt1Aa proteins than without p19 or orf1‐orf2 gene. Electron microscopy observation and bioassay showed that P19 and Orf1‐Orf2 have no influence on the crystal size and toxicity of Cyt1Aa protein. It is presumed that P19 and Orf1‐Orf2 might have negative effects on Cyt1Aa synthesis in B. thuringiensis.  相似文献   
176.
Thermostable direct hemolysin (TDH) is a possible virulence factor produced by Vibrio parahaemolyticus. Although TDH has a variety of biological activities, including hemolytic activity, the biochemical mechanism of action remains uncertain. Here we analysed biochemical events, especially phosphorylation, caused by TDH in erythrocytes, and found that TDH caused significant phosphorylations of proteins on erythrocyte membrane. Phosphorylation of proteins was studied using γ-32P ATP and SDS-PAGE. A number of protein kinase inhibitors were tested, to determine which types of kinases were involved in the phosphorylation events. TDH induced the phosphorylation of two proteins on membranes of human erythrocyte that are sensitive to TDH. The estimated molecular weight of these proteins was 25 and 22.5 kDa. Interestingly, the 22.5 kDa, but not the 25 kDa protein, was phosphorylated on the membrane of TDH-insensitive (resistant) horse erythrocytes. Moreover, a mutant TDH (R7), which retained binding ability but lost hemolytic activity, also phosphorylated only the 22.5 kDa protein on human erythrocyte membranes. Among the protein kinase inhibitors used the protein kinase C inhibitors, (staurosporine and calphostin C) showed marked inhibition of phosphorylation of 25 kDa protein. In addition to phosphorylation, these protein kinase C inhibitors suppresssed hemolysis by TDH. These results indicate that the phosphorylation of the 25 kDa protein seems to be essential for the hemolysis by TDH after it binds to erythrocyte membranes.  相似文献   
177.
The surface pressure-area (-A) isotherms ofN-hexadecyl-8-hydroxy-2-quinolinecarboxamide (HHQ) monolayers at an air-water interface on subphases with different pH values were investigated. The monolayer of HHQ was expanded and unstable on acidic subphases, while it was condensed and stable on basic subphases. The acid-base equilibrium of HHQ was investigated in an aqueous dioxane solution and at the air-water interface. The association-dissociation of HHQ with H+ ions in the interfacial region was very different from that in the aqueous dioxane solution. Some information regarding the packing density, phase transition and degree of ionization of the head group under different experimental conditions has been obtained.  相似文献   
178.
叶片阶段性白化小麦是一种非常特殊的色素突变体。本文对其白色、白绿相嵌及转绿叶片的叶绿体光化活性分别进行了测定。试验表明:(1)白化和白绿相嵌叶片的叶绿体色素合成处于停滞阶段,转绿叶片则处于色素迅速合成阶段;(2)白化、白绿相嵌和转绿叶片叶绿体的激发能传递呈递增趋势;(3)三者对绿体的PSⅡ活性和原初光能转化效率也呈递增趋势;(4)白化叶片叶绿体缺乏PSⅠ和PSⅡ外周天线色素蛋白,白绿相嵌和转绿叶片的类囊体膜多肽组分与正常叶片相近似。  相似文献   
179.
本研究在离体大鼠肠系膜血管床灌流模型上,采用特异放免法测定灌流液中的降钙素基因相关肽(CGRP),观察几种常见炎症介质在内毒素引起CGRP释放中的作用。结果显示:前列腺素合成酶抑制剂地塞米松、布洛芬与消炎痛,缓激肽受体B2拮抗剂HOE140,血小板激活因子拮抗剂WEB2086,组胺H1受体拮抗剂苯海拉明以及和组胺H2受体拮抗剂西咪替丁,均能明显抑剂制内毒素引起的CGRP释放,5羟色胺受体拮抗剂ICS205930却无明显作用。从而提示:内毒素引起CGRP释放是通过炎症介质前列腺素、缓激肽、血小板激活因子和组胺介导的,阻断或减少炎症介质的产生可望减轻内毒素血症时CGRP的过量释放。  相似文献   
180.
癫痫对大鼠学习记忆的影响及与生长抑素的相关性研究   总被引:5,自引:1,他引:4  
对听源性癫痫大鼠进行迷宫训练,观察癫痫发作对大鼠光分辨学习作业的成绩以及用放射免疫分析法测定的大鼠部分脑区中生长抑素含量的影响。结果表明:(1)癫痫发作对大鼠记忆阶段有明显的抑制作用(P<0.01);(2)癫痫发作后,在大鼠信息提取明显障碍的同时,其颞叶皮层、下丘脑、垂体及海马中生长抑素的含量明显增加(P<0.05-0.01)。结果提示:癫痫发作影响大鼠学习记忆过程,在该过程中生长抑素含量发生改变。  相似文献   
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