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61.
AIM:To investigate expression and function of CD40 ligand by peripheral blood mononuclear cells (PBMCs) in patients with systemic lupus erythematosus (SLE).METHODS:Expression of CD40 ligand by PBMCs in patients with SLE and control were examined by flow cytometric analysis before and after stimulated by phytohemagglutinin(PHA)and depressed by Dexamethasone(Dex). The correlation between expression of CD40 ligand and SLE activity index(SLEDAI) was analysed in patients with SLE.RESULTS:The expression of CD40 ligand by PBMCs in patients with active SLE was higher than that in patients with inactive SLE and control. Though the expression of CD40 ligang by PBMCs could be stimulated by PHA in three groups, it was the highest in patients with active SLE. Dex depressed the expression of CD40 ligand by PBMCs significantly in patients with SLE, but not in control. There was high positive correlation between expression of CD40 ligand and SLEDAI in patients with active and inactive SLE.CONCLUSION:Increased expression of CD40L by PBMCs in patients with SLE may play an important role in pathogenesis of SLE.  相似文献   
62.
AIM:To explore the mechanism of neuronal injury and repair by investigating the expression of caspase-3 and apurinic/apyrimidinic endonuclease (APE/Ref-1) after focal cerebral ischemia. METHODS:A model of middle cerebral artery occlusion in rats was performed. The expression of caspase-3P20 and APE/Ref-1 was examined by immunohistochemistry staining, TUNEL was applied to detected DNA damage, and double labeling with TUNEL and APE/Ref-1 was used to determine the relationship between APE/Ref-1 and DNA damage. RESULTS:The active subunit P20 of caspase-3 was predominantly expressed within ischemic penumbra. The peak time of caspase-3P20 positive cells preceded the appearance of TUNEL. With aggravation of cerebral ischemia, APE/Ref-1 immunoreactive cells in penumbra were significantly decreased. CONCLUSION:The activation of caspase enzymatic cascade following cerebral ischemia leads to degradation in DNA, meanwhile, decrease in DNA repair molecules or the failure of DNA repair may deteriorate the course.  相似文献   
63.
AIM:To examine the relationship between the activity of matrix metallproteinases(MMPs) and ventricular remodeling following myocardial ischemia in the rat.METHODS:The model of myocardial ischemia(MI) in the rat was established by isoprenaline(ISP). The activity of MMPs was measured by zymography and collagen concentration was assessed by the method of chloramine T, so did I/III collagen ratio by immunohistochemical staining. The microstructure of myocardium was also observed by electron microscope.RESULTS:The activity of MMP-2 in myocardial ischemia group (group M) increased by 5.8 folds at 1 st week(P<0.01), 2.3 folds at 2 nd week(P<0.01) and 1.7 flods at 4 th week(P<0.05) compared with control group (group C) and MMP-9's activity in group M increased by 4.9 folds (P<0.01), 1.9 flods(P<0.01) and 1.4 folds(P<0.05), respectively. Collagen amount and I/III collagen ratio in group M increased compared with that in group C at 2 nd week and 4 th week. It showed that cardiac myocytes in group M were necrosed and collagen grew abundantly in interstitium under electron microscope.CONCLUSION:The activity of MMPs in the myocardial interstitium increased following myocardial ischemia, then collagen amount and I/III collagen ratio increased, which may be the major causes of ventricular remodeling.  相似文献   
64.
化学防卫是昆虫防御外来侵害的方法之一。简要评述了墨西哥豆瓢虫Epilachna varivestis、南瓜瓢虫Epilachna borealis、苜蓿瓢虫Subcoccinella vigintiquatuorpunctata 3种瓢虫蛹分泌的化学防御物质——氮杂大环内酯的结构、生物活性以及生物合成的研究进展。  相似文献   
65.
黑河干流中游地区耗水量变化的历史分析   总被引:9,自引:6,他引:9  
黑河流域水资源极其匮乏 ,加之地区上的配置不均衡和中游地区水土资源的过度开发导致了黑河下游严重生态环境问题 ,已影响到我国北方广大地区生态环境质量 ,受到国家的高度重视和全社会的广泛关注。黑河水资源开发利用主要集中在中游地区 ,该区是全国重要的商品粮、蔬菜和经济作物生产基地之一 ,耗水量占流域耗水量的 85 %以上 ,是黑河的主要耗水区和径流利用区。本文利用黑河上游控制站莺落峡站和中游控制站正义峡站水文资料 ,分析了黑河中游耗水量的变化 ,结果表明 :2 0世纪 80年代以前黑河中游耗水量在 4.2 0× 10 8m3 左右 ,比较稳定 ;进入 2 0世纪 80年代以来耗水量明显增加 ,80年代耗水量比 40年代末期至 70年代增加了 2 .0× 10 8~ 2 .5×10 8m3 左右 ;90年代耗水量又比 80年代增加了 1.6 0× 10 8m3 左右。 80年代以来流域耗水量呈明显增加的趋势 ,这是以人类活动影响为主的结果  相似文献   
66.
苏云金芽孢杆菌cry基因在大肠杆菌中表达产物和生物活性   总被引:4,自引:0,他引:4  
研究了几种Bt cry基因于大肠杆菌(Escherichia coli)中表达产物在pH 10.0的50mmol/L碳酸钠和20mmol/L乙醇胺溶解液中的溶解性 ,发现同样的Cry蛋白在碳酸钠中的溶解度大于乙醇胺。通过胰蛋白酶消化 ,明确Cry1Ca7、Cry1Ia8酶解产物为 38kD多肽 ;Cry1Ie1、Cry1Cb2、Cry2Ab4酶解产物为 41kD多肽 ;Cry1Ac酶解产物为60kD多肽。采用FPLC层析方法对 6种原毒素及其酶解后得到的毒素多肽进行了分离纯化 ,比较了原毒素和毒素的杀虫活性的差异。其结果表明 ,Cry1Ac的原毒素和毒素对棉铃虫初孵幼虫的校正死亡率均为 100% ,Cry2Ab4的原毒素的毒力高于其酶解毒素。  相似文献   
67.
菊花18个品种的RAPD分析   总被引:25,自引:3,他引:25  
秦贺兰  游捷  高俊平 《园艺学报》2002,29(5):488-490
 采用RAPD 技术分析了18 个菊花品种DNA 的多态性。从80 个10 碱基随机引物中筛选出多态性频率高的3 个引物。扩增的多态性片段在600 bp~1300 bp 之间。检测出两个品种特有的分子标记, ‘大红托桂’有OPD15 (1200 bp) ,‘玉翎管’缺失OPA17 (1100 bp) 。瓣型一致的品种间基因型相似系数较高。  相似文献   
68.
AIM:To explore the expressive profile of nestin protein in the focal ischemic brain and to study the recovery mechanism of brain focal infarct.METHODS:Cellular morphology,time-course and distribution pattern of nestin positive response were immunohistochemically examined in different brain regions of 36 adult male SD rats. RESULTS:Nestin positive response of different brain regions in sham operated rats was present in small- and micro-vasculartures and the third ventricle bottom and ependyma. A large number of nestin positive cells were detected in ischemic brain, and were more remarkable in the cortical areas of parietal lobe and preoptic area as well as ischemic caudoputamen. Stellate nestin positive cells were located in the deep layer of ischemic cortex, but fibrillary cells were located in the shallow layer. Nestin positive cells in the ischemic caudoputamen showed the same changes of morphology as those cells in the deep layer of ischemic cortex. Morphological and number alterations of nestin positive cells were the most remarkable at 1 weeks post-ischemia, which showed more hypertrophy and proliferation in morphology, and a marked increase in number was present in the ischemic cerebral cortex and the ischemic caudoputamen. These alterations of nestin positive cells persisted up to 6 weeks post-ischemia, and then, the nestin positive response in the ischemic brain decreased gradually.CONCLUSION:Focal cerebral ischemia induces nestin re-expression on reactive astrocytes, which may be very important to the self-recovery of cerebral infarct.  相似文献   
69.
AIM:To investigate the effect of lansoprazole on gastric ulceration in rats. METHODS:Using the gastric ulcer model induced by hemorrhagic shock, restraint water-immersion stress and pylorus-ligature, the protective effect of lansoprazole (iv) on gastric ulceration was observed. RESULTS:Pretreatment with lansoprazole (7.5-60 mg/kg) significantly inhibited the formation of gastric ulcer in the three models in a dose-dependent manner. The autiulcer efficacy of lansoprazole was similar to that of omeprazole in the equal dose, but stronger than that of omeprazole for ulcer induced by water-immersion stress.CONCLUSION:The intravenously administered lansoprazole inhibited formation of experimental gastric ulcer in rats.  相似文献   
70.
AIM: To study the effects of tetrandrine(Tet) and fructose-1, 6-diphosphate(FDP) on the elevated intrasynaptosomal [Ca2+]i induced by excitatory amino acids(EAA). METHODS: A rapid method for preparing synaptosomes was used, and intrasynaptosomal free calcium([Ca2+]i) was measured by using the fluorescent indicator quin-2. RESULTS: L-glutamate(Glu, 100 μmol/L), aspartate(Asp, 100 μmol·L-1), N-methy1-D-aspartate(100 μmol/L) and Glu(50 μmol/L) plus Asp(50 μmol/L) all elevated intrasynaptosomal [Ca2+]i in a dose-dependent manner. Pretreatment with Tet(10, 30, 60 μmol/L), FDP(15, 30, 75, 150 μmol/L), MK-801(10, 20 μmol/L) and Tet(15, 30 μmol/L) plus FDP(15, 30 μmol/L) all attenuated the increase in intrasynaptosomal [Ca2+]i induced by EAAs mentioned as above in a dose-dependent manner, and the effect of Tet plus FDP was most significant. CONCLUSION: Both Tet and FDP inhibited a rise in intrasynaptosomal [Ca2+]i induced by EAAs, which may be one of mechanisms that Tet and FDP pretect cerebral tissues against ischemia injury.  相似文献   
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