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41.
电脉冲介导基因转移效率的实验研究 总被引:6,自引:0,他引:6
目的 研究电脉冲介导的基因转移效率及其最佳的基因转移的电脉冲参数。方法 用微量注射器将pcD2/LacZ质粒10μg,在昆明小鼠的股四头肌注射,1~2min内在注射部位给予不同参数的电脉冲刺激(不同的电脉冲参数每组10只小鼠),然后进行β-半乳糖苷酶活性的测定或酶组织化学染色。同时设空白对照组及单纯注射组。结果 电脉冲可明显增加LacZ基因的表达,电脉冲组的β-半乳糖苷酶活性(131.6U/mg±86.5U/mg蛋白)是单纯注射组(4.9U/mg±1.0U/mg蛋白)的30倍(P<0.05)。组织化学染色结果表明电脉冲组肌肉组织中β-半乳糖苷酶蓝色颗粒的数目和染色的程度均明显高于单纯肌肉注射组。当电脉冲参数电压200V/cm,波宽40ms,脉冲次数6次和频率1Hz时,可获得最高的基因表达效率。结论 在最佳的电脉冲参数条件下,电脉冲介导的基因转移可获得较高的基因表达。 相似文献
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目的探讨不稳定性心绞痛患者血清hs—CRP、TnI、CK—MB变化及测定的临床意义。方法利用乳胶增强免疫比浊法和电化学发光法,对154例健康人群、112例uA患者、68例SA患者检测其血清hs—CRP、TnI和CK—MB的水平。结果UA组hs-CRP、TnI、CK—MB水平明显高于SA组(P〈0.01),更远远高于健康组(P〈O.01),并且sA组此三项检测也明显高于健康组(P〈0.05),UA组和SA组及健康组存在显著差异。结论如果将hs—CRP、TnI、CK—MB联合检测,对冠心病的早期诊断,尤其是对不稳定性心绞痛的早期发现及危险性预测,具有重大的现实意义。 相似文献
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COHEN M.; PARRY G.; ADAMS P.C.; XIONG J.; CHAMBERLAIN D.; WIECZOREK I.; FOX K. A. A.; KRONMAL R.; FUSTER V.; THE ANTITHROMBOTIC THERAPY IN ACUTE CORONARY SYNDROMES RESEARCH GROUP 《European heart journal》1994,15(9):1196-1203
The aim of this trial was to compare the efficacy of combinationantithrombotic therapy with a prostacyclin-sparing aspirin plusanticoagulation versus conventional aspirin plus anticoagulation,when added to antianginal therapy, in patients with unstableangina or non-Q wave myocardial infarction already being treatedwith aspirin. In a double-blind (for the aspirin) study, 144prior aspirin users were randomized; 72 patients received controiled-release,prostacyclin-sparing aspirin 75 mg daily plus anticoagulation(intravenous heparin followed by warfarin to maintain the internationalnormalized ratio at 23), and 72 patients received conventionalaspirin 75 mg daily plus the same anticoagulation. Controlled-releaseaspirin was formulated to preserve endothelial cell prostacyclinsynthesis. Trial therapy was begun by 13.2 ± 12.3 h ofqualifying pain, and continued for 12 weeks. The frequency of recurrent angina with electrocardiographicchanges, myocardial infarction, or death, was analysed by intentionto treat. At 12 weeks, events were 相似文献
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During a multiple-casualty incident, a large casualty caseload adversely affects the quality of trauma care given to individual patients. From a trauma care perspective, the goal of the hospital emergency plan is to provide severely injured patients with a level of care that approximates the care given to similar patients under normal conditions. Therefore, the realistic admitting capacity of the hospital is determined primarily by the number of trauma teams that the hospital can recruit. Effective triage of these casualties is often not straightforward, with high overtriage rates. Simplified triage algorithms may be a practical alternative to more elaborate schemes. The concept of minimal acceptable care is the key to a staged management approach during a mass-casualty incident. Discrete-event computer simulation and war game tabletop exercises for key personnel are 2 new modalities that are supplementing the traditional mock disaster drill as effective planning and training tools. 相似文献
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Summary The levels of insulin antagonism exhibited by human plasma albumin samples extracted by the alcoholic-trichloroacetic acid (TCA) method were found to vary over a wide range. Similar variations were found in the chlorine contents of these albumin samples, thus indicating a variation in TCA content. Chlorine content correlated with the levels of antagnonism exhibited by the various samples. Both chlorine levels and antagonistic activity were reduced appreciably by chromatography with Dowex 50W ion exchange resin. When Dowex treated (nonantagonistic) albumin was dissolved in water and re-extracted by the TCA-ethanol method, the resulting albumin preparations were high in chlorine content and highly antagonistic toward insulin. Nonantagonistic albumin was rendered antagonistic by the addition of TCA. The levels of antagonism exhibited by the TCA treated albumin preparations correlated with their chlorine contents. It is concluded that at least a portion of the insulin inhibitory effects exhibited by albumin preparations isolated by the TCA-ethanol method is due to TCA which is bound to the protein. 相似文献
46.
Brittany R. Alperin Katherine K. Mott Dorene M. Rentz Phillip J. Holcomb Kirk R. Daffner 《Psychophysiology》2014,51(7):620-633
An age‐related “anterior shift” in the distribution of the P3b is often reported. Temporospatial principal component analysis (PCA) was used to investigate the basis of this observation. ERPs were measured in young and old adults during a visual oddball task. PCA revealed two spatially distinct factors in both age groups, identified as the posterior P3b and anterior P3a. Young subjects generated a smaller P3a than P3b, while old subjects generated a P3a that did not differ in amplitude from their P3b. Rather than having a more anteriorly distributed P3b, old subjects produced a large, temporally overlapping P3a. The pattern of the age‐related “anterior shift” in the P3 was similar for target and standard stimuli. The increase in the P3a in elderly adults may not represent a failure to habituate the novelty response, but may reflect greater reliance on executive control operations (P3a) to carry out the categorization/updating process (P3b). 相似文献
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