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71.
In this technical note we describe the setup and application of automated sample preparation and usage of flow-through NMR equipment for the characterization of ligand binding on proteins. In addition, we focus on the perspectives of automated analysis of 2D HSQC spectra to identify changes in patterns indicative for ligand binding or changes of sample conditions. In this context we discuss a combination of statistical and non-statistical data analysis.  相似文献   
72.
将ADA-LacZ融合基因经直接注射导入小鼠皮肤组织,用注射点处的皮肤组织制作冰冻切片,经组织化学方法显示:此融合基因可在皮肤成纤维细胞中表达一种具有腺苷脱氨酶(ADA)和β-半乳糖昔酶(β-gal)双重酶活性的融合蛋白,这种直接将融合基因导入体内进行表达的方式.为在基因治疗和基因疫苗研究中探索一条新的简便可行的外源基因在体内表达的途径,提供了有益的实验依据。  相似文献   
73.
参麦注射液抗心肌缺氧-再给氧损伤实验研究   总被引:3,自引:0,他引:3  
采用Langendorf离体心脏灌注模型,对大鼠心肌缺氧—再给氧损伤中抗自由基酶SOD和GSH-Px,过氧化产物MDA、心肌酶CPK和心肌细胞超微结构进行了观察、同时探讨了参麦注射液的保护作用机理。结果表明:(1)心肌缺氧灌注40min,富氧再灌5min,与正常对照组比较,心肌细胞超微结构损伤严重,线粒体数目减少,大部分空泡变性,嵴消失,糖原颗粒减少,心肌收缩结构受到严重破坏。同时CPK活性明显升高,SOD及GSH-Px活性明显降低,MDA含量明显升高(P<0.01)。(2)预先给不同剂量参麦注射液进行灌注,与模型组比较,心肌超微结构损伤明显减轻,线粒体数目较多,嵴密集,未见肿胀变形,糖原颗粒丰富,心肌收缩结构基本正常。CPK活性明显降低,心肌SOD及GSH-Px活性明显增高,心肌MDA含量明显降低(P<0.01)。且参麦大剂量组疗效优于复方丹参液(P<0.05)。我们推测其保护作用机理可能是稳定心肌细胞膜,保护心肌线粒体,增加能量供应,提高抗自由基酶活性,从而减轻氧自由基对心肌的损害  相似文献   
74.
Expressionofmilkproteingenesisinvolvedinahugenetworkofregulatorycircuitswhicharelinkedtotheintactdevelopingmammarygland,andhomeostasisduringpuberty,pregnancy,lactationandinvolution.Analysisofputativeregulatoryelementsandhybridgeneintissueculturesystems…  相似文献   
75.
The recently conducted ADAURA trial concludes daily dosing of adjuvant osimertinib, a third-generation EGFR tyrosine kinase inhibitor (TKI), improves disease-free survival with stage IB/II/IIIA EGFR -mutated non-small cell lung cancer patients in comparison to placebo. We have developed a preclinical orthotopic mouse model, using luciferase tagged lung adenocarcinoma cells harboring EGFR TKI sensitive exon 19 deletion to model and extend trial implications comparing a weekly vs daily dosing outcome of osimertinib to a first-generation TKI- erlotinib. We find that 100% of mice in both the groups receiving osimertinib daily or weekly before injection of cells show a complete absence of homing of cells in mice''s lungs from day three until day 18 post-injection of cells. On the other hand, 25% and 75% of mice receiving erlotinib daily and weekly before injecting cells show homing of cells to the lungs. The tumors observed in the lungs, when dissected at day 30, confirmed the colonization of the injected cells homing to the organ. Thus, our study establishes the efficacy of pretreatment with osimertinib in reducing tumor cells'' homing to mouse lungs in an in vivo mouse model.  相似文献   
76.
Transient expression of liposome-encapsulated DNA in liver after intravenous injection to rats and mice has raised questions concerning the intracellular fate of this DNA. Electron microscope autoradiography shows that at 10 min after injection the highest concentration of liposomal DNA which is taken up by the liver is associated with lysosomes and vesicles. The proportion of DNA associated with the mitochondria steadily increases for 1 h after injection, up to 48% of the exogenous DNA found in the tissue. Part of this DNA follows the subcellular fractionation profile of the mitochondrial matrix marker, malate dehydrogenase. In contrast, 14% of the liposomal DNA taken up by the liver is found in the nuclei at 3 min after injection, and this percentage decreases over a period of 1 h. These results permit us to establish the distribution of liposome-encapsulated DNA among subcellular organelles in liver at different times after injection.  相似文献   
77.
Inadequate oxygen concentration in the root zone is a constraint to plant performance particularly in heavy, compacted and/or saline soils. Sub-surface drip irrigation (SDI) offers a means of increasing oxygen to plant roots in such soils, provided irrigation water can be hyper-aerated or oxygenated. Hydrogen peroxide (HP) at the rate of 5 litre ha−1 at the end of each irrigation cycle was injected through SDI tape to a field-grown zucchini (courgette) crop (Cucurbita pepo) on a saturated heavy clay soil in Queensland, Australia. Fruit yield, number and shoot weight increased by 25%, 29% and 24% respectively due to HP treatment compared to the control. Two pot experiments with vegetable soybean (Glycine max) and cotton (Gossypium hirsutum) compared the effectiveness of HP and air injection using a Mazzei air injector (a venturi), throughout the irrigation cycle in raising crop yield in a heavy clay soil kept at saturation or just under field capacity. Fresh pod yield of vegetable soybean increased by 82–96% in aeration treatments compared with the control. The yield increase was associated with more pods per plant and greater mean pod weight. Significantly higher above ground biomass and light interception were evident with aeration, irrespective of soil water treatment. Similarly cotton lint yield increased by 14–28% in aeration treatments compared with the control. The higher lint yield was associated with more squares and bolls per plant which accompanied greater above ground biomass and an increase in root mass, root length and soil respiration. Air injection and HP effected greater water use, but also brought about an enhancement of water use efficiency (WUE) for pod and lint yield, and increased leaf photosynthetic rate in both species but had no effect on transpiration rate and stomatal conductance per unit leaf area. Aeration-induced enhanced root function was arguably responsible for greater fruit set and yield in all three crops, while in vegetable soybean greater canopy cover, radiation interception and total vegetative biomass were responsible for additional yield benefit. Increased aeration of the root zone in heavy clay soils employing either air injection or HP proved beneficial to SDI irrigated crops, irrespective of the soil water conditions, and can add value to grower investments in SDI.  相似文献   
78.
人巨细胞病毒(HCMV)是疱疹病毒中最大也是最常见的一种,HCMV感染危害性大,亚洲与非洲地区的人群感染率高,目前临床仍缺乏专属性强的治疗药物。在其治疗过程中,抗病毒药物长期应用导致耐药问题存在,而机体免疫功能抑制与病毒耐药发生率关系密切,因此HCMV防治过程中,抗病毒抗氧化协同治疗势在必行。洁罗维注射液(阿昔洛韦氯化钠注射液Ⅱ)是一种"抗病毒+抗氧化+营养支持"三重作用机制的新型复方抗病毒输液,可提高机体免疫功能,降低病毒耐药性,有利于临床诸多科室HCMV感染的预防与治疗,具有极高的临床推广价值。  相似文献   
79.
目的:本文用慢病毒定点注射的方法构建了在下丘脑中过表达mi R-505的小鼠模型,并利用荧光原位杂交方法在冰冻切片组织上快速检测mi RNAs,以确认慢病毒载体介导的mi R-505在丘脑中的表达能力。方法:实验小鼠在脑立体定位仪下定位到下丘脑位置,采用原位注射的方式进行慢病毒注射,注射后采用实时荧光定量RCR和应用了LNA探针和TSA系统的FISH(fluorescence in situ hybridization)技术,完成在慢病毒介导的mi R-505过表达老鼠下丘脑区域细胞中的mi R-505检测和示踪。结果:mi R-505慢病毒注射未成年小鼠下丘脑区5、10、20和40天后,均可检测到mi R-505在下丘脑区域的表达,且实验结果表明在慢病毒介导的过表达小鼠下丘脑注射部位,mi R-505表达量有明显的提高。结论:利用慢病毒注射未成年小鼠下丘脑脑区的方法,成功的建立了下丘脑中过表达mi R-505的小鼠模型,使用LNA标记探针的FISH方法探索mi RNA表达规律较稳定,且重复率高。  相似文献   
80.
目的:探析参芎葡萄糖注射液与脑蛋白水解物联合治疗急性脑梗塞患者的临床疗效和对神经功能、血液流变学的影响。方法:入选急性脑梗患者130例,随机分为两组各65例。对照组在常规治疗基础上使用脑蛋白水解物治疗,治疗组在常规治疗基础上不仅使用脑蛋白水解物,还加用参芎葡萄糖注射液治疗,比较两组患者的临床效果、神经功能缺损评分改变和血液流变学情况。结果:治疗组有效率显著高于对照组(P0.05);神经功能缺损评分治疗后均有下降,但治疗组下降幅度更大(P0.05);治疗组红细胞压积、血小板聚集率和纤维蛋白原均显著下降(P0.05),且同期相比,治疗组纤维蛋白原和红细胞压积下降幅度显著优于对照组(P0.05)。结论:参芎葡萄糖注射液与脑蛋白水解物联合治疗急性脑梗塞患者疗效确切,安全可靠,值得临床推广。  相似文献   
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