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431.
We interviewed 51 blood donors in four major US metropolitan areas subsequently found to have had antibodies to human T-cell lymphotropic virus (anti-HTLV) in late 1984-early 1985. Sixteen donors (31%) reported that they or a sexual contact had a history of blood transfusion. Twelve donors (24%) reported that they or a sexual contact used intravenous drugs. Ten donors (20%) were blacks born in the southeastern US. Four of the male donors (15%) reported homosexual contact. The most common characteristic was an association with Japan or the Caribbean basin (61%). These results show a broader variation of epidemiologic backgrounds than anticipated.  相似文献   
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目的:探讨miR-95与胃癌细胞洛铂敏感性的关系及作用机制。方法:收集30例手术切除的胃癌组织及癌旁组织标本,实时定量PCR(qPCR)法检测组织中miR-95的表达情况,CCK-8法检测洛铂对胃癌组织细胞的体外抑制率。采用miR-95抑制物(anti-miR-95)和miR-95模拟物(miR-95 mimics)分别转染人胃癌细胞株SGC7901,检测转染前后细胞对洛铂敏感性的变化;采用qPCR及Western blot法检测细胞耐药相关基因MDR1、GST-π、LRP、Survivin、xIAP、Bad mRNA和蛋白的表达。结果:qPCR检测结果显示,30例胃癌组织miR-95的相对表达水平(0.106±0.023)显著高于癌旁组织(0.046±0.025)(P < 0.05)。以miR-95表达均值为界将胃癌组织分为miR-95高表达组17例,低表达组13例。洛铂对miR-95表达水平高的胃癌细胞的抑制率低于miR-95低水平者(P < 0.05)。anti-miR-95转染后,SGC7901细胞对洛铂的敏感性明显增高(P < 0.01),耐药相关基因MDR1、Survivin、xIAP mRNA和蛋白表达水平明显降低(P < 0.05),而Bad mRNA和蛋白表达水平明显增高(P < 0.05)。miR-95 mimics转染后,洛铂对SGC7901细胞的抑制率明显增加(P < 0.01),耐药相关基因MDR1、Survivin、xIAP mRNA和蛋白表达水平明显升高(P < 0.05),而Bad mRNA和蛋白表达水平明显降低(P < 0.05)。结论:miR-95通过调节一些耐药基因的表达影响胃癌组织和细胞对洛铂的敏感性。  相似文献   
435.
Background/aim This study was conducted to elucidate the effects of lutein/zeaxanthin isomers (L/Zi) on lipid metabolism, oxidative stress, NF-κB/Nrf2 pathways, and synaptic plasticity proteins in trained rats.Materials and methods Wistar rats were distributed into four groups: 1) control, 2) L/Zi: rats received L/Zi at the dose of 100 mg/kg by oral gavage, 3) exercise, 4) exercise+L/Zi: rats exercised and received L/Zi (100 mg/kg) by oral gavage. The duration of the study was eight weeks. Results Exercise combined with L/Zi reduced lipid peroxidation and improved antioxidant enzyme activities of muscle and cerebral cortex in rats (p < 0.001). In the Exercise + L/Zi group, muscle and cerebral cortex Nrf2 and HO-1 levels increased, while NF-κB levels decreased (p <0.001). Also, L/Zi improved BDNF, synapsin I, SYP, and GAP-43 levels of the cerebral cortex of trained rats (p < 0.001). The highest levels of BDNF, synapsin SYP, and GAP-43 in the cerebral cortex were determined in the Exercise+L/Zi group.Conclusion These results suggested that exercise combined with L/Zi supplementation might be effective to reduce neurodegeneration via improving neurotrophic factors and synaptic proteins, and oxidative capacity in the cerebral cortex.  相似文献   
436.
Background/aimTo investigate the changes in the spleen size, parenchymal heterogeneity, and computed tomography (CT) texture analysis features of patients diagnosed with Coronavirus disease 2019 (COVID-19)Materials and methodsThe size and parenchymal structure of the spleen in 91 patients who underwent thoracic CT examination due to COVID-19 were evaluated. For the evaluation of parenchymal heterogeneity, CT texture analysis was performed using dedicated software (Olea Medical, France). The texture analysis of each case consisted of 15 first-order intensity-based features, 17 gray level co-occurrence matrix-based features, and 9 gray level run length matrix-based features.ResultsA total of 91 patients (45 males, 46 females) with a mean age of 54.31 ± 16.33 years (range: 18–81) were included in the study. A statistically significant decrease in spleen size was seen in the follow-up CT examinations (p < 0.001) whereas no statistically significant difference was found between the Hounsfield unit (HU) values. The radiomics consisted of first-order intensity-based features such as 90th percentile, maximum, interquartile range, range, mean absolute deviation, standard deviation, and variance, all of which showed statistically significant differences (p - values: < 0.001, < 0.001, 0.001, 0.003, 0.001, 0.001, and 0.004, respectively). “Correlation” as a gray level co-occurrence matrix-based feature and “gray level nonuniformity” as a gray level run length matrix-based feature showed statistically differences (p-values: 0.033 and < 0.001, respectively).ConclusionsAlthough COVID-19 manifests with lung involvement in the early stage, it can also cause systemic involvement, and the spleen may be one of its target organs. A decrease in the spleen size and parenchymal microstructure changes can be observed in the short follow-up time. It is hoped that the changes in the parenchymal microstructure will be demonstrated by a noninvasive method: texture analysis.  相似文献   
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