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191.
192.
Experimental evaluation of calcein and alizarin red S for immersion marking of silver carp Hypophthalmichthys molitrix (Valenciennes, 1844) 下载免费PDF全文
Calcein (CAL) and alizarin red S (ARS) at concentrations of 50–200 and 150–300 mg/L, respectively, were used for immersion marking of juvenile silver carp Hypophthalmichthys molitrix (79.65 ± 2.11 mm total length, mean ± SD). The marked fish were kept in separate tanks (0.012 individuals per litre, rearing temperature 18.4–25.7°C) for 360 days. Each experimental treatment group consisted of three replicates (16 individuals per replicate). Immersion for 24 h produced detectable marks in the sagittae, lateral line and non‐lateral line scales, and fin rays (dorsal, pectoral, ventral, anal, and caudal) at 360 days post‐marking. Acceptable marks in the sagittae were observed for CAL at concentrations of 150–200 mg/L and for ARS at concentrations of 200–300 mg/L. Fluorescent marks were poorly visible in all non‐lateral line scales from both the CAL‐ and ARS‐treated groups. Acceptable fluorescent marks in the lateral line scales and fin rays were detected for CAL at concentrations of 150–200 and 100–200 mg/L, respectively, and for ARS at concentrations of 200–300 and 150–300 mg/L, respectively. In particular, optimal marks were observed at the highest concentrations investigated in lateral line scales (200 mg/L CAL, 300 mg/L ARS) and fin rays (200 mg/L CAL, 200–300 mg/L ARS). There was no significant difference in the survival or growth of marked fish compared to controls throughout the experiment (P > 0.05). 相似文献
193.
Lifang Zou Guihua Tu Wei Xie Shiyao Wen Qiuyu Xie Shuangmei Liu Guilin Li Yun Gao Hong Xu Shouyu Wang Yun Xue Bing Wu Qiulan Lv Mofeng Ying Xi Zhang Shangdong Liang 《Purinergic signalling》2016,12(1):127-137
Adenosine triphosphate (ATP) acts on P2X receptors to initiate signal transmission. P2X7 receptors play a role in the pathophysiological process of myocardial ischemic injury. Long noncoding RNAs (lncRNAs) participate in numerous biological functions independent of protein translation. LncRNAs are implicated in nervous system diseases. This study investigated the effects of NONRATT021972 small interference RNA (siRNA) on the pathophysiologic processes mediated by P2X7 receptors in stellate ganglia (SG) after myocardial ischemic injury. Our results demonstrated that the expression of NONRATT021972 in SG was significantly higher in the myocardial ischemic (MI) group than in the control group. Treatment of MI rats with NONRATT021972 siRNA, the P2X7 antagonist brilliant blue G (BBG), or P2X7 siRNA improved the histology of injured ischemic cardiac tissues and decreased the elevated concentrations of serum myocardial enzymes, creatine kinase (CK), CK isoform MB (CK-MB), lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) compared to the MI rats. NONRATT021972 siRNA, BBG, or P2X7 siRNA treatment in MI rats decreased the expression levels of P2X7 immunoreactivity, P2X7 messenger RNA (mRNA), and P2X7 protein, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and phosphorylated p38 mitogen-activated protein kinase (p38 MAPK) in the SG compared to MI rats. NONRATT021972 siRNA treatment prevented the pathophysiologic processes mediated by P2X7 receptors in the SG after myocardial ischemic injury. 相似文献
194.
Ju‐Hong Zhang Shang Wang Shuang Yang Jiankun Yi Yan Liu Jing‐Hui Xi 《Archives of insect biochemistry and physiology》2016,92(4):274-287
To understand the olfactory mechanisms of Holotrichia parallela antennae in detecting volatile compounds in the environment, protein profiles of H. parallela antennae were analyzed using two‐dimensional electrophoresis followed by mass spectrometry and bioinformatics analyses. Approximately 1,100 protein spots in silver staining gel were detected. Quantitative image analysis revealed that in total 47 protein spots showed significant changes in different genders of adult antennae. Thirty‐five differentially expressed proteins were identified by Matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI‐TOF/TOF) tandem mass spectrometer, among which 65.7% are involved in carbohydrate and energy metabolism, antioxidant system, transport, and amino acid/nucleotide metabolism. Some proteins identified here have not been reported previously in insect antennae. Identified male‐biased proteins included odorant‐binding protein 4, pheromone‐binding protein‐related protein 2, odorant‐binding protein 14, prophenoloxidase‐I, acyl‐CoA dehydrogenase, aldo‐keto reductase‐like, carbamoyl phosphate synthetase, etc. whereas some proteins are female biased, such as antennae‐rich cytochrome P450, aldehyde dehydrogenase, and putative glutamine synthetase. Alterations in the levels of some proteins were further confirmed by real time polymerase chain reaction (RT‐PCR). The proteomic resources displayed here are valuable for the discovery of proteins from H. parallela antennae. 相似文献
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Isolation and Identification of Pathogens Causing Marigold (Tagetes erecta L.) Black Spot in Beijing,China 下载免费PDF全文
Dong‐liang Chen Xi Cheng Chang Luo Ming‐yuan Li Qian‐qian Feng Ji‐ye Yan Cong‐lin Huang 《Journal of Phytopathology》2016,164(7-8):547-553
Black spot leads to great marigold losses worldwide. The disease is characterized by black spots on leaves and stems in its early stages, and the whole plant has black rot at the advanced stage. In this report, 6 of 217 Alternaria strains isolated from lesions of marigold plants in Beijing were randomly selected. The morphological characteristics and a pathogenic tree based on two protein‐coding genes (gpd and alt a 1) indicated that Alternaria tagetica is the causal agent of marigold black spot in Beijing. All six Alternaria strains could successfully re‐infect marigold, but they could not infect carrot or zinnia by either spore spray in a greenhouse or planting experiments in the epidemic area. This is the first report of the A. tagetica pathogen being isolated from marigold in Beijing. 相似文献
198.
野鸦椿种子内源抑制物活性初探 总被引:2,自引:0,他引:2
以野鸦椿(Euscaphis japonica)种壳和胚为材料,甲醇浸提得到种壳浸提液和胚浸提液,配制浸提液浓度梯度为原浸提液浓度的10%、20%、30%、40%,研究不同浓度的种壳和胚浸提液对白菜、小麦、绿豆种子底物酶活性、发芽率、幼苗根长和苗高的影响,萃取和分离种壳和胚甲醇浸提液中的内源抑制物质,探讨野鸦椿种子内源抑制物质的活性与成分。结果表明:随着种壳和胚浸提液浓度的增加,白菜种子酸性磷酸酶活性和发芽率均显著降低(P0.05),表现为抑制作用递增,种壳的抑制作用小于胚,而幼苗的根长和苗高则表现为低促高抑,在10%浸提液处理下根长和苗高达最大值,种壳的促进效果弱于胚;小麦种子淀粉酶活性及幼苗的根长和苗高递减(P0.05),表现为抑制作用递增,而发芽率则在浓度≤20%时差异不明显(P0.05),浓度为30%时显著降低(P0.05),40%时发芽率为0,种壳的抑制作用大于胚;绿豆种子蛋白酶活性、发芽率、幼苗根长和苗高均在浸提液浓度≥20%时显著下降(P0.05),且种壳的作用效果小于胚。种子内源抑制物萃取及分离表明,外壳中含酚酸类较胚多,含碱类较胚少。综上认为,野鸦椿种壳和胚中均含有较高活性的内源抑制物,但性质、成分及含量存在差异,外壳内源抑制物主要作用对象为淀粉类物质,胚乳内源抑制物主要作用于油脂类和蛋白类物质。 相似文献
199.
该研究首次以文心兰的类原球茎( protocorm-like bodies, PLBs)为外植体进行愈伤组织诱导及其植株再生培养,并分析了不同浓度的TDZ和2,4-D配比对愈伤组织增殖的影响。结果表明:以1/2MS为基本培养基,添加1 mg.L-1 TDZ与3 mg.L-12,4-D,从接种的 PLBs上可以诱导出乳白色的、较疏松的愈伤组织,诱导频率达到100%。愈伤组织继代培养时,在2,4-D浓度为0.5~2.0 mg.L-1的范围内,其增殖主要受TDZ浓度的影响,TDZ浓度从1.0 mg.L-1降低到0.5 mg.L-1,愈伤组织鲜重增殖倍数显著增加,由最低的4.50倍增加到最高的6.04倍。愈伤组织增殖的最适培养基为1/2MS +0.5 mg.L-1 TDZ +1.0 mg.L-12,4-D。将在最适愈伤组织增殖培养基上继代培养约1个月的愈伤组织转移到T2培养基(3.5 g.L-1花宝1号+20 g.L-1红薯+25 g.L-1香蕉+1 g.L-1 tryptone +20 g.L-1蔗糖+3.5 g.L-1 phytagel)上,黑暗培养1个月后,每克鲜重的愈伤组织约诱导出1328.67个PLBs。将诱导出的PLBs转移到新鲜的T2培养基上光照培养1个月,萌发率为90.12%。而将小植株转移到添加1 g.L-1活性炭的1/2MS培养基上,成苗率达到100%。该研究结果成功建立了文心兰的高频愈伤组织诱导及其植株再生体系,为文心兰基因工程育种提供了一个高效、稳定的转化受体系统。 相似文献
200.
裂解多糖单加氧酶高效催化的研究进展 总被引:1,自引:0,他引:1
裂解多糖单加氧酶(lytic polysaccharide monooxygenases,LPMOs)是一类新发现的铜离子依赖性的氧化酶,常具有多种模块化组合,能够高效氧化降解生物质多糖.LPMOs的催化结构域为β三明治结构,活性中心含有一个铜离子.该酶的催化反应过程相对于糖苷水解酶类更加复杂,LPMOs结合底物后,首先要接受电子供体提供的电子,通过电子传递链传递给活性中心的Cu[Ⅱ],将其还原为Cu[Ⅰ],Cu[Ⅰ]结合并活化分子氧后,再氧化降解多糖链的糖苷键,生成氧化产物和非氧化产物.近年来的研究表明,在木质纤维素降解酶系中加入LPMOs能显著提高其对结晶纤维素的转化效率,因此LPMOs相关研究的深入开展可以拓展人们对其高效降解机制的认识,从而为高效降解酶系的复配以降低工业规模的生产成本等提供理论指导.本文综述了该领域相关研究的最新进展,分析了LPMOs潜在的研究方向与工业化应用的前景. 相似文献