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971.
AIM: To investigate the effect of flavonoids from stem and leaf of Scutellaria baicalonsis Georgi (SSF) on paired helical filament (PHF) abnormality and the regulatory mechanism of protein phosphatase (PP) in rats' brain induced by okadaic acid (OA). METHODS: Male Sprague-Dawley (SD) rats were microinjected with OA (200 ng/kg) by the lateral ventricle to establish a memory impairment model. Morris water maze was used to screen the memory impairment model. The successful model rats were continuous intragastric infusion (ig) SSF for 36 days. The relative protein expression of PHF, PP1, PP2A-Cα, PP2A-Cβ, PP2CA and PP2CB in the rat cerebral cortex and hippocampus were detected by Western blot. GinKgo biloba leaf flavonoids (GLF) were used as positive control drug. RESULTS: Compared with the sham-operated rats, the relative protein expression of PHF in the cerebral cortex and hippocampus and PP1 in cortex of model rats were significantly increased (P<0.01), and the protein expression of PP2A-Cα, PP2A-Cβ in the cerebral cortex and hippocampus and PP2CB in the hippocampus were decreased (P<0.05), while the relative protein expression of PP2CA and PP2CB in the cortex were significantly increased (P<0.01). SSF reversed the abnormality in the protein expression of PHF, PP2A-Cα and PP2A-Cβ in rat cortex and hippocampus and PP1 in rat cortex induced by OA (P<0.01), which had no significant effect on the relative protein expression of PP2CA and PP2CB. GLF also showed similar results to SSF. CONCLUSION: SSF significantly reduces the abnormal formation of PHF in rats' brain induced by OA, which may be related to the regulation of PP1, PP2A-Cα and PP2A-Cβ expression, but not with PP2CA and PP2CB expression.  相似文献   
972.
AIM: To investigate the effects of transplantation of bone marrow mesenchymal stem cells (BMSCs) modified by bcl-2 gene on myocardial cell apoptosis, angiogenesis and cardiac function in the rabbit after acute myocardial infarction (MI).METHODS: The rabbit BMSCs were isolated, cultured and purified in vitro. The BMSCs were transfected with adenovirus or adenovirus-Bcl-2. The rabbit model of MI was established by ligation of left anterior descending branch. The rabbits were injected with Ad-Bcl-2-BMSCs (MI+Bcl-2-BMSCs group), Ad-BMSCs (MI+BMSCs group) and DMEM (MI group) in infarction marginal zone 2 weeks after ligation. The cardiac function was evaluated by echocardiography.The apoptosis of myocardial cells was measured by TUNEL. The mRNA expression of VEGF was detected by real-time PCR. The expression of CD31 was examined by immunohistochemical staining, and new blood capillaries were counted at 4 weeks after BMSCs transplantation. The correlation of the above values with cardiac function was analyzed.RESULTS: The cardiac function was better, the apoptotic rate was lower, the mRNA expression of VEGF and the capillary density were higher in both MI+Bcl-2-BMSCs group and the MI+BMSCs group than those in MI group, and those in MI+Bcl-2-BMSCs group increased more obviously.The left ventricular ejection fraction (LVEF) had a negative correlation with the myocardial cell apoptosis rate. A positive correlation with the mRNA expression level of VEGF and the capillary density was also observed.CONCLUSION: The transplantation of BMSCs modified by bcl-2 gene significantly reduces the myocardial cell apoptosis, promotes angiogenesis, improves heart function of the rabbits with MI.  相似文献   
973.
墨兰炭疽病菌生物学特性研究   总被引:3,自引:0,他引:3  
高洋  刘爱媛  冯淑杰  张荣 《北方园艺》2010,(24):170-171
以墨兰炭疽病菌为试材,研究墨兰炭疽病菌的生物学特性。结果表明:菌丝生长和孢子萌发最适温度为26℃,产生孢子最适温度为30℃;菌丝生长最适pH为7~8,产生孢子最适pH为7~9,孢子萌发最适pH为7;26℃下连续光照产孢量最多;相对湿度低于81%时分生孢子不能萌发。  相似文献   
974.
介绍了改进亚硫酸法的国内外动态和新工艺的技术原理和技术成熟度、工艺路线、技术指标,提出了一种改进亚硫酸法新工艺,即利用蔗渣生产的制糖专用吸附剂,去除蔗汁中的色源物质(色素)、胶体、残硫等物质,使糖厂生产出低硫、低色值、低浊度的优质糖,从根本上达到提高白砂糖质量的目的。  相似文献   
975.
通过调查中华常春藤的生境和测量茎的生长情况,总结了中华常春藤的种植特点和分枝方式,同时利用SPSS软件的回归分析建立回归模型,并根据建立的模型用Excel软件绘制坐标图。结果表明:中华常春藤主枝生长完毕所需的有效积温为2 718.34℃/d;茎伸长量随有效积温延续的变化呈"S"形曲线,而茎伸长速度变化趋于钟罩型单峰曲线。再利用此结果估算出:在理想的生长条件下采用三角形定植方式定植中华常春藤为宜,并且植株与植株之间的最佳定植密度为510 mm×510 mm。  相似文献   
976.
采用HPLC方法测定“红圆”芜菁(HY)和“白玉”芜菁(BY)肉质根和叶片中芥子油苷(GS)成分和含量.结果表明:不同品种芜菁以及同一品种不同部位中芥子油苷(简称GS)含量差别较大.在“红圆”芜菁肉质根中检测出11种GS,在其叶片中检测出9种GS;“红圆”根中主要为苯乙基GS和2-羟基-3-丁烯基GS,分别占总硫苷的37.2%和20.9%,根中总GS含量是叶中的2.1倍.在“白玉”芜菁肉质根中检测出9种GS,主要GS种类为3-丁烯基GS和苯乙基GS,分别占总GS的65.6%和23.4%;在“白玉”芜菁叶片中含8种GS,不合有苯乙基GS,“白玉”叶中GS总量是根中含量的1.2倍.  相似文献   
977.
综述了黄檗的主要病虫害种类、为害特点和生物学特性,并提出了无公害防治措施,可为进一步做好黄檗病虫害防治工作,保护现有黄檗资源及其可持续研究和利用提供参考.  相似文献   
978.
以14份乌腺金丝桃为试材,采用L_(16)(4~5)正交实验设计,建立并优化乌腺金丝桃的ISSR-PCR反应体系,并利用优化的反应体系分析供试材料间的遗传多样性。结果表明:20μL ISSR-PCR反应体系中应含有Taq DNA聚合酶1.0U,dNTPs 0.2mmol·L~(-1),Mg~(2+)2.0mmol·L~(-1),模板DNA 45ng。从45条ISSR引物中筛选出11条多态性引物,利用筛选的多态引物对14份乌腺金丝桃材料进行了ISSR遗传多样性分析,共扩增出85条带,其中多态性条带57条,占67.06%;4个乌腺金丝桃居群的遗传相似系数介于0.375 1~0.725 2,平均值为0.541 6;通过UPGMA进行聚类分析表明,14份材料可分为3个类群4个亚群。乌腺金丝桃居群间遗传多样性水平明显高于居群内,其遗传距离与地理距离具有一定的相关性。  相似文献   
979.
高红治  张媛  辛铭霞 《北方园艺》2018,(11):178-182
通过对沈阳市5区县蔬菜种植户的调研及数据整理,分析了沈阳市蔬菜种植的成本收益,并与全国大中城市的蔬菜生产成本收益进行比较,以了解沈阳市蔬菜生产的优势和特点,可为政府及相关部门发展蔬菜产业提供决策依据。结果表明:1)沈阳市蔬菜种植从业人员年龄偏大、文化程度较低,加快对新型职业农民的培育,留住或吸引一批知识青年从事蔬菜生产经营对产业发展意义重大;2)相对于露地蔬菜,设施蔬菜具有高投入、高产量、高收益的特点,沈阳市设施蔬菜的收益是全国大中城市收益的5.7倍,应加快发展设施蔬菜,尤其是推进高标准、规模化建设;3)大城市周边受人工和土地成本的压力,应以提高劳动生产率为前提,通过资金扶持、科技支撑等手段发展规模种植、特色种植,以提高蔬菜种植收益,保障蔬菜供应。  相似文献   
980.
AIM:To examine the effect of compound salvae-dropping-pill (CSDP) on intracellular free calcium in cultured rat myocardial cells subjected to hypoxia and reoxygenation.METHODS:The Fluo- 3/AM was applied to probe intracellular calcium concentration and the fluorescent intensity was detected using laser confocal microscopy technique.RESULTS:Fluorescent intensity in hypoxia plus CSDP group was significantly lower (1 217.78±312.07) than that of hypoxia group (1 509±508.48), and the Fluorescent intensity of hypoxia/reoxygenation plus CSDP group was also markedly lower (1 567.91±577.61) than that of hypoxia/reoxygenation group (1 617.60±477.53).CONCLUSION:The cultured rat myocardial cells could be effectively protected by administration of CSDP in case of hypoxia and reoxygenation through decreasing the intracellular calcium concentration.  相似文献   
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