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71.
目的观察耐力训练和一次性力竭运动对大鼠骨骼肌线粒体通透性转换孔(mitochondrial permeability transi-tion pore,MPTP)相关因素及细胞凋亡的影响。方法 24只大鼠随机分为3组:对照组(C组)、耐力训练组(T组)和一次性力竭组(E组)。T组进行无负重游泳训练,6次/周,共6周,训练时间从每天45 min逐渐增加到90 min;E组正常笼内饲养6周后进行一次力竭性游泳运动。通过紫外分光光度仪检测MPTP的开放;Western blot检测细胞色素c(Cyt c)的释放;RT-PCR检测Bcl-2和Bax mRNA;双光束紫外分光光度仪检测线粒体Ca2+的转运。结果与对照组相比:(1)T组线粒体吸光度值和Ca2+的转运量无显著性变化,Cyt c的释放量与Bax mRNA的表达显著减少,Bcl-2 mRNA的表达显著增加;(2)E组线粒体吸光度值显著减少,Cyt c释放量及Ca2+转运量显著增加,Bcl-2mRNA表达显著下降,Bax mRNA表达显著增强。结论 耐力运动可能通过上调Bcl-2/Bax基因表达,减少Cyt c释放,稳定MPTP开放,从而减少细胞凋亡;一次性力竭运动可能通过下调Bcl-2/Bax基因表达,MPTP异常开放,增加Cyt c和Ca2+释放,促进细胞凋亡。  相似文献   
72.
Le texte rédigé par Sālih b.Yahyā constitue une source primordiale pour létude des expéditions militaires mameloukes contre Chypre entre 1424 et 1426 car l’auteur a joué un rôle principal dans la deuxième et la troisième attaque. Â la différence d'autres chroniqueurs arabes, Sālih b.Yahyā fournit des informations importantes qui permettent de reconstruire les événements et de comprendre le fonctionnement de la marine mamelouke.  相似文献   
73.
β-Amylase activity (BAA) and thermostability (BAT) are important traits for malt quality. In this study, 138 Tibetan annual wild barley accessions and 20 cultivated genotypes differing in BAA were planted and analyzed in 2009 and 2012. Significant differences were detected among genotypes in BAA and BAT. The cultivated genotypes had a mean BAA of 1137.6 U/g and a range of from 602.1 to 1407.5 U/g, while the wild accessions had a mean of 1517.9 U/g and a range of from 829.7 to 2310.0 U/g. The cultivated genotypes had a mean relative residual β-amylase activity (RRBAA) of 61.6% and a range of from 22.2% to 82.3%, while the wild barleys had a mean of 57.8% and a range of from 21.9% to 96.1%. Moreover, there was a significant difference among genotypes in the response of RRBAA to the temperature and duration of heat treatment. The wild barleys had wider variation in BAA and BAT than cultivated genotypes.  相似文献   
74.
Preeclampsia is a multisystem disorder associated with maternal hypertension, placental abnormalities and adverse fetal outcomes. The various pathways involved in its etiology include endothelial dysfunction, inflammatory milieu, lipid peroxidation and immunological imbalance. The present study was conducted to evaluate the causative and predictive role of nitric oxide, lipid peroxidation end products (MDA) and inflammatory cytokines (IL-6, TNF-α) in clinical presentation, severity and fetal outcome in preeclampsia. The study population was divided into 3 groups- Non- pregnant females comprising the control population; G1 and G2 groups included normal pregnant and pregnant females with preeclampsia with 50 patients in each group. Nitric Oxide and MDA levels were found to be highest in the preeclamptic patients as compared to other two groups. ROC curve analysis shows the superiority of the inflammatory markers as determinants of severity of preeclampsia which suggests the emerging role of pro inflammatory markers in the various pathological changes in preeclampsia. TNF-α emerged as the best marker in multivariate analysis and thus, has the potential for being used as a marker for PIH. Our study illustrates the multifactorial etiology of preeclampsia involving oxidative stress, proinflammatory milieu and endothelial dysfunction.  相似文献   
75.
The pathogenesis of idiopathic nephrotic syndrome is not completely understood. We postulate that cytokine gene polymorphisms may influence susceptibility or clinical course in Idiopathic Nephrotic Syndrome. Polymorphisms of IL-4, IL-6, and TNF-α cytokines were investigated in 150 children with Idiopathic Nephrotic Syndrome and 569 healthy controls by using polymerase chain reaction and restriction fragment length polymorphism. On comparing patient with controls strong association were found for IL-6, TNF-α and IL-4 at allelic level (IL-6-G174C (G vs. C): P = <0.001; OR = 6.33, TNF-α-G308A (G vs. A): P = <0.001; OR = 1.99, IL-4-C590T (C vs. T): P = 0.048; OR = 1.38). Further when SR group was compared with SS group significant association was found at genotypic level in all the studied genetic polymorphisms. Studied cytokine gene polymorphisms may influence susceptibility to idiopathic nephrotic syndrome and might affect steroid response in INS patients.  相似文献   
76.
The ninth/fifteenth century Arabic work, Kharīdat al-?Ajā?ib wa Farī?at al-Gharā?ib, ascribed to Ibn al-Wardī (d. 861/1457), was frequently translated into Ottoman Turkish and widely read by the Ottoman literati between the tenth/sixteenth and thirteenth/nineteenth centuries. The most popular translation of the Kharīdat al-?Ajā?ib that is extant today with more than thirty copies in libraries worldwide was made by the tenth/sixteenth century Ottoman preacher Ma?mūd al-Ha?īb. Within the context of Medieval Islamic cosmographical works and their translations, which have potential to shed light on the Ottoman worldview in the early modern era, this paper delves into the extra-textual statements of the translator in the form of eye-witness accounts and contemporary hearsay. By doing so, it argues that Ma?mūd al-Ha?īb's intervention in the text he translated not only provides him with grounds for confirmation of the worldview promoted in the Kharīdat al-?Ajā?ib, but also expressions on certain issues related to sixteenth century Ottoman rule.  相似文献   
77.
利用纳米磁性颗粒将bFGF定位于大鼠骨骼肌钝挫伤部位,考察该方法对大鼠急性骨骼肌钝挫伤恢复过程中收缩应力及MHC-Ⅱb表达影响。研究结果表明,bFGF对大鼠腓肠肌钝挫伤后第17、24天的收缩力有明显提高。损伤后第2~10天,bFGF包裹组与其余各组之间的MHC-ⅡbmRNA表达差异显著(P<0.05)。因此,磁纳米化的bFGF能明显改善大鼠急性骨骼肌钝挫伤后的收缩应力衰减,显著促进损伤肌肉MHC-ⅡbmRNA的表达,改善损伤肌肉再生和结构修复。  相似文献   
78.
In this ITEMS module, we frame the topic of scale reliability within a confirmatory factor analysis and structural equation modeling (SEM) context and address some of the limitations of Cronbach's α. This modeling approach has two major advantages: (1) it allows researchers to make explicit the relation between their items and the latent variables representing the constructs those items intend to measure, and (2) it facilitates a more principled and formal practice of scale reliability evaluation. Specifically, we begin the module by discussing key conceptual and statistical foundations of the classical test theory model and then framing it within an SEM context; we do so first with a single item and then expand this approach to a multi‐item scale. This allows us to set the stage for presenting different measurement structures that might underlie a scale and, more importantly, for assessing and comparing those structures formally within the SEM context. We then make explicit the connection between measurement model parameters and different measures of reliability, emphasizing the challenges and benefits of key measures while ultimately endorsing the flexible McDonald's ω over Cronbach's α. We then demonstrate how to estimate key measures in both a commercial software program (Mplus) and three packages within an open‐source environment (R). In closing, we make recommendations for practitioners about best practices in reliability estimation based on the ideas presented in the module.  相似文献   
79.
设a和b是两个不同的实数,如果一个矩阵的元素为a或b,我们称这样的矩阵为(a,b)矩阵。根据a、b的不同取值分三种情形给出了n阶非奇异对称(a,b)矩阵中元素a的可能个数。  相似文献   
80.
To correlate blood lead levels (BLLs) and oxidative stress parameters in pregnant anemic women. A total of 175 pregnant women were found suitable and included for this study. Following WHO criteria, 50 each were identified as non-anemic, mild anemic and moderate anemic and 25 were severe anemic. The age of all study subjects ranged from 24–41 years. At admission, BLLs and oxidative stress parameters were estimated as per standard protocols and subjected with ANOVA, Pearson correlation analysis and cluster analysis. Results showed significantly (p < 0.01) high BLLs, zinc protoporphyrin (ZPP), oxidized glutathione (GSSG), lipid peroxide (LPO) levels while low delta aminolevulinic acid dehydratase (δ-ALAD), iron (Fe), selenium (Se), zinc (Zn), haemoglobin (Hb), haematocrit (Hct), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), red blood cell (RBC) count, reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and total antioxidant capacity (TAC) in all groups of anemic pregnant women as compared with non anemic pregnant women. In all groups of pregnant women, BLLs showed significant (p < 0.01) and direct association with ZPP, GSSG and LPO while inverse relation with δ-ALAD, Fe, Se, Zn, Hb, Hct, MCV, MCH, MCHC, RBC, GSH, SOD, CAT and TAC. Study concluded that low BLLs perturb oxidant-antioxidant balance and negatively affected hematological parameters which may eventually Pb to Fe deficiency anemia during pregnancy.  相似文献   
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