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81.
Retroviral resistance mediated by the murine Fv1 gene is believed to result from a direct interaction between the Fv1 gene product and the viral capsid protein. To study the mechanism of Fv1 action, the expression and intracellular localisation of the Fv1 protein were examined. Only very low levels of protein expression seem necessary for virus restriction but the site of expression appears crucial. Active Fv1 was found in association with tubules of the trans-Golgi network, whereas an inactive form was localised in the endoplasmic reticulum. We hypothesize that Fv1 is compartmentalised in the cell on the pathway taken by virus en route to the nucleus, suggesting that incoming virus must pass the trans-Golgi network during its transit to the nucleus. 相似文献
82.
Jingqi Liu Ligang Chen Jinshui Pan Meiya Chen Jingping Zhou Fei Zhou Peizhong Chen Yang Song 《Archives of Medical Science》2021,17(1):142
IntroductionHepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Despite the therapeutic advances in HCC in the past few decades, the mortality rate of HCC is still high. Hepatitis C (HCV) infection is one of the major etiological risk factors of HCCs. However, the underlying mechanisms of HCV-induced hepatocarcinogenesis remain largely unclear.Material and methodsOur study represented the comprehensive analysis of differentially expressed lncRNAs in HCV-positive HCC for the first time by analyzing the public dataset . Co-expression network and gene ontology (GO) analysis revealed the functions of those differentially expressed lncRNAs.ResultsWe identified 256 upregulated lncRNAs and 198 downregulated lncRNAs in HCV- positive HCC compared to the normal liver tissues. Co-expression network and GO analysis showed that these lncRNAs were involved in regulating metabolism, energy pathways, proliferation and the immune response. Seven lncRNAs (LOC341056, CCT6P1, PTTG3P, LOC643387, LOC100133920, C3P1 and C22orf45) were identified as key lncRNAs and co-expressed with more than 100 differentially expressed genes (DEGs) in HCV-related HCC. Kaplan-Meier analysis showed that higher expression levels of LOC643387, PTTG3P, LOC341056, CCT6P1 and lower expression levels of C3P1 and C22orf45 were associated with shorter survival time in the TCGA dataset.ConclusionsWe believe that this study can provide novel potential therapeutic and prognostic biomarkers for HCV-positive HCC. GSE17856相似文献
83.
Gaetano Scala Paolo De Girolamo Mario Corona Gaetano Vincenzo Pelagalli 《Anatomical record (Hoboken, N.J. : 2007)》2002,266(1):58-68
The microvasculature of the water buffalo (Bubalus bubalis) epididymis was investigated using light (LM), scanning electron (SEM), and transmission electron (TEM) microscopy techniques. SEM analysis of the buffalo epididymis showed fenestrations that occupied ovoid inside the endothelium of the postcapillary venules located in the caput, corpus, and cauda. They varied in shape and dimension, but more importantly, they connected the venules of the blood vascular system to the capillaries of the peripheral lymphatic vascular system. Morphofunctional analysis of these connections suggests that the microvasculature of the buffalo epididymis plays a role in facilitating the circulation of biologically active substances, and the absorption and secretion processes necessary for the survival and maturation of spermatozoa. The lymphatic capillaries at the connection points formed a network of variously sized polygonal links. These capillaries then converged to form the precollector lymphatic vessels, which in turn converged with the larger vessels originating from the testis. It was further noted that in the capillary endothelium there were no fenestrations, and in the large veins there were many diverticula. These diverticula appear to play a role in the regulation of the seasonal variations of the blood reflux. In general, the microvascular architecture of the buffalo epididymis, particularly its connection to the lymphatic vascular system, appears to play an important role in the absorption and secretion processes of the epididymal epithelium. Anat Rec 266:58–68, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
84.
Dr. Y. Fukuoka M. Noshiro H. Shindo H. Minamitani M. Ishikawa 《Medical & biological engineering & computing》1997,35(1):33-39
The nonlinearity included in the PCO
2 control system in humans is evaluated using the degree of nonlinearity based on a difference of residuals. An autoregressive
moving average (ARMA) model and neural networks (linear and nonlinear) are employed to model the system, and three types of
network (Jordan, Elman and fully interconnected) are compared. As the Jordan-type linear network cannot approximate respiratory
data accurately, the other two types and the ARMA model are used for the evaluation of the nonlinearity. The results of the
evaluation indicate that the linear assumption for the PCO
2 control system is invalid for three subjects out of seven. In particular, strong nonlinearity was observed for two subjects. 相似文献
85.
Heinzerling L Frew AJ Bindslev-Jensen C Bonini S Bousquet J Bresciani M Carlsen KH van Cauwenberge P Darsow U Fokkens WJ Haahtela T van Hoecke H Jessberger B Kowalski ML Kopp T Lahoz CN Lodrup Carlsen KC Papadopoulos NG Ring J Schmid-Grendelmeier P Vignola AM Wöhrl S Zuberbier T 《Allergy》2005,60(10):1287-1300
Skin prick testing (SPT) is the standard method for diagnosing allergic sensitization but is to some extent performed differently in clinical centres across Europe. There would be advantages in harmonizing the standard panels of allergens used in different European countries, both for clinical purposes and for research, especially with increasing mobility within Europe and current trends in botany and agriculture. As well as improving diagnostic accuracy, this would allow better comparison of research findings in European allergy centres. We have compared the different SPT procedures operating in 29 allergy centres within the Global Allergy and Asthma European Network (GA(2)LEN). Standard SPT is performed similarly in all centres, e.g. using commercial extracts, evaluation after 15-20 min exposure with positive results defined as a wheal >3 mm diameter. The perennial allergens included in the standard SPT panel of inhalant allergens are largely similar (e.g. cat: pricked in all centres; dog: 26 of 29 centres and Dermatophagoides pteronyssinus: 28 of 29 centres) but the choice of pollen allergens vary considerably, reflecting different exposure and sensitization rates for regional inhalant allergens. This overview may serve as reference for the practising doctor and suggests a GA(2)LEN Pan-European core SPT panel. 相似文献
86.
预测非编码RNA对认识其调控功能具有重要意义。选择单核苷酸和二核苷酸出现频率作为神经网络分类特征,运用主成分分析方法降低输入数据的维数,去除数据间的相关性,采用Levenberg-Marquardt算法改善网络训练速度。对数据集的测试结果表明,此方法对细菌混合ncRNA的预测精度达到81.3%,对原核生物tRNA的预测精度达到93.3%,表明该方法能有效预测原核生物ncRNA。预测结果还发现两种古细菌的ORF序列在序列特征上与其它细菌和古细菌存在差别。 相似文献
87.
88.
采用多分辨率分析和人工神经网络相结合的方法实现对心室晚电位的检测。首先利用多分辨率分解技术提取高分辨率心电信号不同频带的能量构成一组特征值 ,再利用这些特征值训练BP神经网络 ,并完成对心室晚电位的识别。经过对 2 8例 3导高分辨率心电图实验数据的处理 ,取得了较高的识别准确率 相似文献
89.
应用模糊极小极大神经网络研究了化合物复杂结构和性能(QSAR)之间的关系,用该法进行几组化合物致癌的识别,结果优于线性回归的方法,对此作出一些分析。 相似文献
90.
一种EEG信号盲分离和分类的神经网络方法 总被引:2,自引:1,他引:2
提出一种采用多神经网络处理脑电(EEG)信号的方法。首先,对混有噪声的脑电信号给出一种盲分离的自适应神经算法。通过寻求采样时间序列线性组合的kurtosis系数的局部极值,得出该算法的模型和步骤。在盲分离的基础上,对分离出的估计信号进一步利用Kohonen网络进行分类。将该算法用于300个EEG样本处理,并给出处理结果。 相似文献