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91.
Xiao-Yong Luo 《Pesticide biochemistry and physiology》2004,78(2):93-102
In order to clarify the action mechanism of fluazifop-butyl, an aryloxyphenoxypropionate (AOPP) herbicide in bristly starbur (Acanthospermum hispidum DC.), a unique fluazifop-butyl-susceptible broad-leaved weed, ethylene evolution and membrane lipid peroxidation in the plant seedlings were investigated. Foliar application of fluazifop-P-butyl induced ethylene evolution only from bristly starbur, but not from oat (Avena sativa L.), another fluazifop-butyl-susceptible species, and two tolerant species, pea (Pisum sativum L.) and hairy beggarticks (Bidens pilosa L.). The other AOPP herbicides, quizalofop-ethyl and fenoxaprop-ethyl, and a cyclohexanedione (CHD) herbicide, sethoxydim, did not enhance ethylene production from bristly starbur. This fluazifop-butyl-induced ethylene production in bristly starbur was completely suppressed by aminoethoxyvinylglycine (AVG), a 1-aminocyclopropane-1-carboxylic acid (ACC) synthase inhibitor, but not by p-chlorophenoxyisobutyric acid (PCIB), an anti-auxin compound, suggesting this evolved ethylene was not auxin-induced. Phytotoxic action by fluazifop-P-butyl (5 μM) in bristly starbur was reduced markedly by two lipid-soluble antioxidants, vitamin E, and ethoxyquin. The ethylene production from the plant was also inhibited by these two antioxidants. Content of malondialdehyde, an indicator of lipid peroxidation, increased only by fluazifop-P-butyl in bristly starbur seedlings but not in oat, and this increase was inhibited by ethoxyquin. These results strongly suggest that the primary site of action for fluazifop-butyl in bristly starbur is on the membranes and active oxygen species and/or free radicals are involved in peroxidation. Ethylene evolution is probably induced by these reactive oxygen species. 相似文献
92.
人们对等离子喷涂工艺试验研究得比较充分,但对涂层性能尤其是经过重熔处理的涂层性能研究很少。本文概括地介绍了等离子喷涂重熔技术在拨丝机塔轮产品强化和旧件修复上的应用。并以此为基础,重点研究了重熔涂层的性能,如结合强度、摩擦学行为等,分析了涂层缺陷及产生的原因。从而为拨丝机塔轮的表面强化和修复提供了指导性资料。 相似文献
93.
Trumel C Diquélou A Germain C Palanché F Braun JP 《Research in veterinary science》2005,79(3):183-189
The suitability of the Spotchem 4430 benchtop biochemistry analyzer for canine blood samples was tested for creatinine, glucose, proteins, urea, alkaline phosphatases and alanine aminotransferase. Results obtained from whole blood and corresponding heparin plasma were identical except for proteins which were higher in plasma (n=10). Between series imprecision (n=10) was <5% for substrates and <10% for enzymes. Comparison of results from 100 Li-heparin samples with those measured with a Vitros 250 analyzer showed good correlation (r>0.93). The slopes of the Passing-Bablock's regression ranged from 0.90 to 1.20 and intercepts were low. The mean biases were low, except for creatinine for which the results obtained by Spotchem (Jaffe reaction) were about 20 micromol/L higher than with the Vitros (enzymatic reaction). The results of this study show that the Spotchem analyzer is suitable for use in canine whole blood or plasma when small numbers of tests are to be performed and large analyzers are not available. 相似文献
94.
Forterre S Raila J Forterre F Brunnberg L Schweigert FJ 《Veterinary journal (London, England : 1997)》2006,171(3):451-455
The aim of this study was to investigate differences in concentrations of vitamin A, transthyretin (TTR) and retinol-binding protein (RBP) between plasma and cerebrospinal fluid (CSF) in dogs. RBP was detected using ELISA, and both RBP and TTR by Western blot analysis after separation on SDS-PAGE. Vitamin A was determined by high performance liquid chromatography. RBP and TTR as well as vitamin A were detected in all samples but at substantially lower concentrations in CSF compared to plasma. RBP in dog plasma showed a similar molecular mass to that of humans, whereas canine TTR had a lower molecular mass. Comparison between plasma and CSF showed that both RBP and TTR were of lower molecular mass in CSF. In CSF, RBP and retinol were present at 10-100-fold lower concentrations compared to plasma. Retinyl esters were present only in minute amounts in 5/17 samples. In conclusion, the CSF of dogs compared to humans is significantly different in terms of both quality and quantity of transport proteins for vitamin A. 相似文献
95.
综述了植物质膜和液泡膜H+-ATPase的结构特征、生理功能和活性变化的研究进展。 相似文献
96.
97.
质量控制图是以高等数学的概率论及统计检验为理论基础而建立的一种既便于直观地判断分析质量又能全面、连续地反映分析测试结果的波动状况的图形,是用于常规检测质量控制的一种有效方法。将质量控制图和空白值的检验结合起来,不仅可以实现检出限的检验,而且可以动态地控制试验的各个方面的条件。该方法的推广运用可以提高实验室的分析测试和质量管理水平,保证数据质量。 相似文献
98.
[目的]考察膜生物反应器(MBR)对生活污水中COD和氨氮的去除效果。[方法]以成都市第二污水处理厂进水为中试用水,采用由自主开发的聚偏氟乙烯制成的高性能中空纤维膜材料做的膜组件进行中试研究,试验工艺为A/O-MBR,对MBR在实际废水中的性能进行评估。[结果]采用MBR处理生活污水,对CODCr去除率平均水平在90%以上,且在进水CODCr波动比较大的情况下,保持相90%以上。运行期间,回流量维持在5 m3/h,出水流量在1.3~2.2 m3/h变动,相应的HRT在6.7~12.0 h变动,但出水水质并没有较大变化,说明MBR系统对HRT的要求并不高。[结论]MBR对生活污水中的COD和氨氮具有良好的去除效果。 相似文献
99.
100.
Recent advances in genome analysis and biochemical pathway mapping have advanced our understanding of how biological systems have evolved over time. Protein and DNA marker comparisons suggest that several of these systems are both ancient in origin but highly conserved into today's evolved species. However, remnants of some of the more ancient functions of these chemical systems can run in conflict with the functions that those same pathways serve in complex organisms and tissue systems today. Relevant to the present topic, nitric oxide (NO) and superoxide anion (O2•−), ancient cellular molecules in evolutionary terms, are recognized today as both necessary for the well-being and stable health of cells but also injurious to cells as elaborated in conjunction with the cellular stress response. Why the dichotomy? This question underlies one of the basic issues challenging researchers as well as practitioners in their approach to disease management. The fundamental proinflammatory response of the innate immune system of the host is needed for pathogen control but can be injurious to tissues from “collateral damage” from NO- and O2•−-derived reactive molecules capable of affecting protein function via post-translational chemical modification. This review highlights newer aspects of the biochemistry of the NO- and O2•−-mediated innate proinflammatory response and further show how protein and tissue damage via overproduction of reactive nitrogen and oxygen intermediary molecules such as peroxynitrite (ONOO−) might be targeted to specific epitopes of proteins. Changes in the regulation of metabolism in response to proinflammatory disease states are discussed for GH signal transduction and tissue specificity. 相似文献