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991.
992.
AIM:To study the effects of synthetic kainic acid (SKA) and 1-heptanol (1-Hep), a gap junction blocker, on the cytoskeletal filament expression in the astrocytes. METHODS:The neonatal rat brain was obtained from the Wistar rats (1 day old) and primary purified astrocytes were obtained by differential attachment for removing filamentoblasts and orbital shaker for removing the oligodendrocytes. The effects of SKA and other interventions on the morphologic changes and expression levels of skeleton protein filamentous actin (F-actin) were observed in the astrocytes after 24 h of the exposures by laser scanning confocal microscopy. The effect of 1-Hep on the expression of F-actin was also explored. RESULTS:Compared with control group, the fluorescence intensities in KCl group and KCl+SKA group were increased, and highly increased in KCl+SKA group. The F-actin filaments in the above 2 groups were more intensive, thickened and concentrated than those in control group, and more obvious in KCl+SKA group. l-Hep significantly decreased the expression of F-actin in KCl group and KCl+SKA group as compared with control group, and parts of the filamentous fracture were seen in the astrocytes in all 1-Hep-treated groups, in which some of the filamentous lines were crosscut. CONCLUSION:Increase in the expression of F-actin in the astrocytes affects the structure and function of the intercellular gap junctions, which may be involved in the mechanism of SKA-induced epilepsy. 相似文献
993.
“马家沟芹菜”作为蔬菜类地理标志农产品的典型代表,经过多年的培育,已经成为我国知名的品牌。本文从“马家沟芹菜”的历史形成、品牌培育以及发展和保护等方面进行系统阐述。 相似文献
994.
WANG Xin-shi ZENG Qing-yi ZHU Zhen-guo ZHU Pan XU Hui-qin ZHENG Rong-yuan 《园艺学报》2014,30(12):2254-2258
AIM:To study the effect of idazoxan (IDA) on the permeability of blood-brain barrier (BBB) and the expression of matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinase 1 (TIMP-1) in mouse experimental autoimmune encephalomyelitis (EAE).METHODS:Female C57BL/6 mice (n=36) were randomly divided into control group, EAE group and IDA group, with 12 mice in each group. EAE was induced by myelin oligodendrocyte glycoprotein 35-55 (MOG35-55). IDA (2 mg/kg, ip, bid) was administered for 15 d after immunization. The neurological defects of the mice were observed daily and scored. The pathological changes were observed under microscope with HE staining and LFB myelin staining. The BBB permeability was detected by Evans blue extravasation. The expression of MMP-9 and TIMP-1 in the brain of EAE mice was determined by Western blotting.RESULTS:Compared with EAE group, the score of neurological defects in IDA group was decreased, the inflammation was relieved, the BBB permeability was reduced, and the expression MMP-9 and the ratio of MMP-9/TIMP-1 were decreased (P<0.05).CONCLUSION:The neuroprotective effect of IDA on mouse EAE might be related to the down-regulation of MMP-9 and the ratio of MMP-9/TIMP-1, thus reducing the degradation of BBB and the permeability of BBB, and ameliorating the pathologic process of EAE. 相似文献
995.
996.
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998.
功能性堆肥及其浸提液在设施温室甜瓜栽培上的应用研究 总被引:3,自引:0,他引:3
以甜瓜蜜世界为试材,采用单因素完全随机设计,研究了功能性堆肥及其浸提液对甜瓜生长指标、叶绿素荧光参数、品质、单果质量及产量的影响,探讨堆肥及其浸提液在设施温室甜瓜栽培上的应用效果.为其在植物生产上的应用提供依据。结果表明,堆肥及其浸提液促进根系发育,有利于甜瓜叶面积、茎粗和株高的增加及叶片叶绿素的累积;显著提高qP,对Fv/Fm影响不显著;促进果实营养物质的累积,提高产量且改善品质;使甜瓜提前上市5-6d;降低施肥量63.28%以上,进而减少肥料成本42.86%。 相似文献
999.
芽孢杆菌属细菌在芽孢状态下,对外界环境及理化因素具有高度抵抗力。适宜的温度、湿度及营养条件能促进芽孢萌发,影响其对常规灭菌方法的抵抗力。本试验选取蜡样芽孢杆菌作为研究对象,在适宜培养条件下使其形成芽孢,通过研究萌发后芽孢对温度、H2O2及含氯消毒剂等条件的抵抗力,证实了适当的条件(温度37 ℃、湿度40%、pH 7.4、30 min)能有效促进蜡样芽孢杆菌芽孢萌发,致使芽孢对高温(80 ℃、2 h)、H2O2(1.5 mol/L、2 h)及含氯消毒剂(有效氯含量约800 mg/L、2 h)等常规灭菌方法抵抗力明显降低,并能被有效杀灭和灭活,相对有效杀灭率分别达98.4%、98.9%及99.1%,有效杀灭率分别为88.3%、88.7%及88.9%,这对进一步研究芽孢杆菌属细菌的杀菌消毒条件具有重要参考意义。 相似文献
1000.
A Real-time quantitative PCR method was developed for the rapid detection of enterohemorrhagic Escherichia coli (EHEC) O157∶H7 based on the primers and TaqMan probes which were designed for the conservative domain of rfbE gene of EHEC O157∶H7.The results showed that the sensitivity of Real-time PCR was 7.3 CFU/mL.20 from 310 samples of meat,egg,milk and its products,animal diarrhea materials and artificial contamination samples were positive detected by Real-time PCR assay,which was in accordance with the testing result according to AOAC standard.The results indicated that Real-time PCR assay was a sensitive,rapid and simple tool. 相似文献