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71.
经过推导,得出小麦赤霉病的两类药剂防治指标模型.在保证品质、收支有余的条件下,第一类模型附加产投比较佳、净收益最佳原则,第二类模型附加产投比最佳原则.灵敏度分析和合理性分析证明了模型的正确性.模型可做为小麦赤霉病药剂防治的决策工具.同时,给出了两类模型的BASIC计算程序.  相似文献   
72.
Jiang  Y.  Tsui  C. K. M.  Ahmed  S. A.  Hagen  F.  Shang  Z.  Gerrits van den Ende  A. H. G.  Verweij  P. E.  Lu  H.  de Hoog  G. S. 《Mycopathologia》2020,185(4):613-627
Mycopathologia - Emmonsia crescens is known as an environmental pathogen causing adiaspiromycosis in small rodents. As the generic name Emmonsia is no longer available for this species, its...  相似文献   
73.
Converging evidence indicates that SOD1 aggregation is a common feature of mutant SOD1-linked fALS, and seems to be directly related to the gain-of-function toxic property. However, the mechanism inducing the aggregation is not understood. To study the contribution of oxidative modification of cysteine residues in SOD1 aggregation, we systematically examined the redox state of SOD1 cysteine residues in the G37R transgenic mouse model at different stages of the disease and under oxidative stress induced by H2O2. Our data suggest that under normal circumstance, cysteine 111 residue in SOD1 is free; however, under oxidative stress, it is prone to oxidative modification by providing the thiolate anion (S−). With the progression of the disease, increased levels of oxidative insults facilitated the oxidation of thiol groups of cysteine residues; human mutant SOD1 could generate an upper shift band in reducing SDS-PAGE, which turned out to be a Cys111-peroxidized SOD1 species. We also detected the formation of SOD1 multimers at different stages of the disease, and found that accumulated oxidative stress facilitated the formation of aggregates, which were not mediated by disulfide bond. This oxidative modification of cysteine 111 therefore promotes the formation of disulfide bond-independent aggregation of SOD1.  相似文献   
74.
山西蟒河自然保护区栓皮栎林的聚类和排序   总被引:6,自引:1,他引:6  
本文用等级聚类、极点排序、主成分分析和对应分析等多元分析法, 对蟒河自然保护区的栓皮标(Quercus variabilis)林进与于了聚类和排序。等级聚类法将蟒河自然保护区的栓皮栎林划分为五个群丛, 极点排序、主成分分析和对应分析三种方法得出一致的结论, 并较好地反映了环境变化的梯度及植被变化的连续性。综合分析表明栓皮栎林是保护区内稳定的群落类型。  相似文献   
75.
简要介绍了蝶类与蛾类的区别以及蝶类生命周期的分期,即卵期、幼虫期、蛹期、成虫期和休眠期,并比较详细地介绍了蝶类的卵、幼虫、蛹和成虫的形态、生态和生物学特性。  相似文献   
76.
A novel mercury-doped silver nanoparticles film glassy carbon (Ag/MFGC) electrode was prepared in this study. Electrochemical behaviors of cysteine on the Ag/MFGC electrode were investigated by electrochemical impedance spectroscopy and cyclic voltammetry (CV). The results indicated that cysteine could be strongly adsorbed on the surface of the Ag/MFGC electrode to form a thin layer. The doped electrode could catalyze the electrode reaction process of cysteine, and the cysteine displayed a pair of well-defined and nearly reversible CV peaks at the electrode in an acetate buffer solution (pH 5.0). The Ag/MFGC electrode was used for determination of cysteine by differential pulse voltammetry. The linear range was between 4.0x10(-7) and 1.3x10(-5) mol/L, with a detection limit of 1.0x10(-7) mol/L and a signal-to-noise ratio of 3. The relative standard deviation was 2.4% for seven successive determinations of 1.0x10(-5) mol/L cysteine. The determinations of cysteine in synthetic samples and urinal samples were carried out and satisfactory results were obtained. Amperometric application of the Ag/MFGC electrode as biosensors is proposed.  相似文献   
77.
[目的]肠道是动物的主要消化器官,同时也是机体抵抗外源病原菌的重要屏障,已有研究表明,动物的品种、饲养方式、生长阶段均会影响动物的肠道菌群结构,但对舍饲和放牧饲养条件下藏猪的肠道菌群结构,以及藏猪和长白、约克与杜洛克三元杂交猪(DLY猪)的肠道菌群结构是否有差异,尚未见报道.[方法]本研究选取6-7月龄的放牧藏猪、舍饲...  相似文献   
78.
本文报导五加科一新属,人参本属Chengiopanax Shang et J.Y.Huang,新组合2种,即华人参木Ch.fargesii(Franch.)Shang et J.Y.Hung及人参木Ch.sciadophylloides(Franch.et Sav.)Shang et J.Y.Huang。  相似文献   
79.
A new adsorption chromatography procedure for the purification of calmodulin from bovine brain was developed using polymeric adsorbent 3520. Calmodulin was first isolated by DEAE-Cellulose column chromatography and further purified to apparent homogeneity following elution with 50% ethanol from the adsorbent column. Polyacrylamide gel electrophoresis showed one band either in the presence of Ca2+ or EGTA. The polymeric adsorbent 3520 is a non-polar polymer lacking exchangeable groups. The selective adsorption of calmodulin is based on hydrophobic interaction within the matrix, and is Ca2+ independent. Neither high salt (0.5 M NaC1) nor EGTA (5 mM) was able to elute the CaM from the adsorption column whereas ethanol (50%) eluted it completely. This method is simple to use and it provides highly purified calmodulin with high yield.  相似文献   
80.
Intracellular calcium (Ca(2+)) increases rapidly after heat shock (HS) in the Ca(2+)/calmodulin (Ca(2+)/CaM) HS signal transduction pathway: a hypothesis proposed based on our previous findings. However, evidence for the increase in Ca(2+) after HS was obtained only through physiological and pharmacological experiments; thus, direct molecular genetic evidence is needed. The role of phosphoinositide-specific phospholipase C (PI-PLC) is poorly understood in the plant response to HS. In this work, atplc9 mutant plants displayed a serious thermosensitive phenotype compared with wild-type (WT) plants after HS. Complementation of atplc9 with AtPLC9 rescued both the basal and acquired thermotolerance phenotype of the WT plants. In addition, thermotolerance was even improved in overexpressed lines. The GUS staining of AtPLC9 promoter:GUS transgenic seedlings showed that AtPLC9 expression was ubiquitous. The fluorescence distribution of the fusion protein AtPLC9 promoter:AtPLC9:GFP revealed that the subcellular localization of AtPLC9 was restricted to the plasma membrane. The results of a PLC activity assay showed a reduction in the accumulation of inositol-1,4,5-trisphosphate (IP(3)) in atplc9 during HS and improved IP(3) generation in the overexpressed lines. Furthermore, the heat-induced increase in intracellular Ca(2+) was decreased in atplc9. Accumulation of the small HS proteins HSP18.2 and HSP25.3 was downregulated in atplc9 and upregulated in the overexpressed lines after HS. Together, these results provide molecular genetic evidence showing that AtPLC9 plays a role in thermotolerance in Arabidopsis.  相似文献   
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