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51.
Vilchez RA Lopez-Terrada D Middleton JR Finch CJ Killen DE Zanwar P Jorgensen JL Butel JS 《Virology》2005,342(1):38-46
Simian virus 40 (SV40) is associated with some systemic non-Hodgkin's lymphomas (NHL) among HIV-positive patients, based on assays for viral DNA sequences. To investigate the possible production of the viral transforming protein, we examined age-matched case-control specimens from patients with HIV/AIDS for the expression of SV40 large tumor antigen (T-ag). Masked specimens initially examined by polymerase chain reaction (PCR) for polyomavirus and herpesvirus DNA sequences were assessed for the expression of SV40 T-ag and phenotypic lymphocyte markers by immunohistochemistry (IHC). Fifty-five systemic NHL and 25 nonmalignant lymphoid and malignant nonlymphoid tissue control cases from two HIV community programs in Texas and New Jersey were scored for IHC positivity without knowledge of the PCR results. IHC showed expression of SV40 T-ag among B-cell lymphomas, whereas none of the control tissue samples were positive for T-ag (12/55, 22% vs. 0/25, 0%; P = 0.01). SV40 T-ag expression was detected only in B-cell lymphoma specimens that contained SV40 DNA sequences. Not all lymphoma cells in a positive specimen stained for T-ag, and the reaction was lower intensity than observed in SV40 hamster tumors. SV40 T-ag was demonstrated in both primary and recurrent tumors from one patient. A germinal center B-cell-like (GCB) profile was more frequently expressed by SV40-positive tumors than in Epstein-Barr virus (EBV)-related lymphomas (10/12, 83% vs. 6/13, 46%; P = 0.05), whereas a non-GCB phenotype was more frequent in EBV-positive than in SV40-positive lymphomas (7/13, 54% vs. 2/12, 17%; P = 0.05). This study shows that SV40 gene expression occurs in a fraction of cells in some B-cell lymphomas among patients with HIV/AIDS. 相似文献
52.
目的 检测子宫肌瘤患者信号通路分子及MMPs、IL-6、IL-10及T细胞亚群相关指标并探讨其临床意义.方法 选取海南医学院附属医院妇科2013年1月至2016年10月收治的患子宫肌瘤而行子宫全切除术或子宫次全切除术患者68例作为观察组,选择同期60例因宫颈CINⅢ级行子宫切除术的患者作对照组,采用Western blot检测信号通路分子的含量,免疫组化法测定MMP-2、MMP-7、MMP-9、IL-6、IL-10的含量,S-P法对T细胞亚群相关指标进行检测分析.结果 观察组患者抗氧化信号通路分子ARE、Nrf2含量分别为(79.31±15.24)、(83.53±16.42),明显低于对照组的(227.35±27.17)、(173.41±20.15),增殖信号通路分子Ras、JNK、ERK含量分别为(87.36±13.75)、(92.16±15.31)、(95.47±15.03),高于对照组的(23.69±3.61)、(35.16±6.37)、(34.73±5.81),差异均有统计学意义(P<0.05).观察组血清中MMP-2、MMP-7、MMP-9含量分别为(35.24±3.78)、(25.74±4.63)、(38.56±4.39),均低于对照组的(84.57±17.39)、(94.75±16.57)、(85.73±17.41),观察组IL-6、IL-10水平分别为(28.96±0.68)、(16.37±6.42),低于对照组的(39.18±1.56)、(13.25±2.46),差异均具有统计学意义(P<0.05).观察组外周血CD4+、CD8+及CD4+/CD8+细胞水平分别为(39.63±9.64)%、(29.24±7.62)%、(1.32±0.18),均显著低于对照组(79.82±8.75)%、(38.72±6.21)%、(1.96±0.34),差异均有统计学意义(P<0.05).结论 MMPs、IL-6、IL-10及T细胞亚群相关指标可早期预测子宫肌瘤的发生. 相似文献
53.
Gurevich S Hadani R Sochen N 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(29):9869-9873
A system of functions (signals) on the finite line, called the oscillator system, is described and studied. Applications of this system for discrete radar and digital communication theory are explained. 相似文献
54.
Margaret Gamalo-Siebers Ram Tiwari Lisa LaVange 《Journal of biopharmaceutical statistics》2016,26(6):1040-1055
ABSTRACTThe paradigm shift towards precision medicine reignited interest in determining whether there are differential treatment effects in subgroups of trial participants. Intrinsic to this problem is that any assessment of a differential treatment effect is predicated on being able to estimate the treatment response accurately while satisfying constraints of balancing the risk of overlooking an important subgroup with the potential to make a decision based on a false discovery. While shrinkage models have been widely used to improve accuracy of subgroup parameter estimates by leveraging the relationship between them, there is still a possibility that it can lead to excessively conservative or anti-conservative results. This can possibly be due to the use of the normal distribution as prior, which forces outlying subjects to have their means over-shrunk towards the population mean, and the data from such subjects may be excessively influential in estimation of both the overall mean response and the mean response for each subgroup, or a model misspecification due to unaccounted variation or clustering. To address this issue, we investigate the use of nonparametric Bayes, particularly Dirichlet process priors, to create a flexible shrinkage model. This model represents uncertainty in the prior distribution for the overall response while accommodating heterogeneity among individual subgroups. We simulated data to compare estimates when there is no differential subgroup effect and when there is a differential subgroup effect. In either of these scenarios, the flexible shrinkage model does not force estimates to shrink excessively when similarity of treatment effects is not supported but still retains the attractiveness of improved precision given by the narrower credible intervals. We also applied the same method to a dataset based on trials conducted for an antimicrobial therapy on several related indications. 相似文献
55.
Paul A. Brown Chantal Allée Céline Courtillon Nathan Szerman Evelyne Lemaitre Didier Toquin 《Avian pathology》2019,48(4):311-318
To date, four subgroups of avian metapneumoviruses have been defined (AMPV-A, B, C and D) based on genetic and antigenic differences. The extent of infection in the three principal species (turkeys, chickens and ducks) by these subgroups is, however, not well defined. Here, a series of controlled and ethically approved experimental infections were performed in specific pathogen-free turkeys, chickens and ducks with each of the four AMPV subgroups. For subgroup C, one strain isolated from turkeys in the USA (turkey AMPV-C) and one isolated from ducks in France (duck AMPV-C) were compared. Globally, these extensive experimental trials demonstrated that AMPV-A, B, turkey C and D were well adapted to Galliformes, especially turkeys; however, chickens showed limited clinical signs and differences in seroconversion and transmission. Notably, chickens did not transmit AMPV-A to contacts and were shown for the first time to be susceptible to AMPV-D. The duck AMPV-C was well adapted to ducks; however, chickens and turkeys seroconverted and were positive by virus isolation. In addition, seroconversion of contact turkeys to duck AMPV-C demonstrated horizontal transmission of this virus in a non-palmiped species under our experimental conditions. Interestingly, in chickens and turkeys, duck AMPV-C isolation was possible despite a lack of detection of viral RNA. Likewise, the turkey AMPV-C virus was well adapted to turkeys yet was also isolated from chickens despite a lack of detection of viral RNA. These results would suggest a selection for viral genetic sequences that differ from the original strain upon adaptation to a ‘non-conventional host’. 相似文献
56.
Martin Benesch Martin Mynarek Hendrik Witt Monika Warmuth-Metz Torsten Pietsch Brigitte Bison Stefan M. Pfister Kristian W. Pajtler Marcel Kool Ulrich Schüller Klaus Pietschmann Björn-Ole Juhnke Stephan Tippelt Gudrun Fleischhack Irene Schmid Christof M. Kramm Peter Vorwerk Andreas Beilken Carl Friedrich Classen Pablo Hernáiz Driever Gabriele Kropshofer Thomas Imschweiler Andreas Lemmer Rolf-Dieter Kortmann Stefan Rutkowski Katja von Hoff 《The oncologist》2019,24(9):e921-e929
57.
摘要:目的 了解江苏省男男性行为人群特征,为制定切实有效的干预措施提供依据。方法 采用横断面调查研究的方法,对2013年江苏省男男性行为人群(MSM)进行匿名问卷调查,采集血液进行 HIV和梅毒抗体检测。结果 2013年共招募4208例MSM,样本量以酒吧/歌舞厅/茶室/会所(BDT)1561例最多;MSM以本地未婚青壮年为主,但各亚组间分布差异有统计学意义(P<0.001);同性近6个月无保护性肛交发生率以PTG组最高;异性性行为安全套坚持使用率以ELSE组最好;近1年STD患病率以BSM(9.0%)最高;HIV阳性率以ELSE(11.9%)最高;HIV相关危险因素及服务,HIV阳性率方面各亚组分布差异有统计学意义(P<0.001)。结论 江苏省不同性活动场所的MSM人群在人口学、高危性行为、HIV阳性率方面存在显著差异,提示在制定MSM的干预措施应该有所侧重。 相似文献
58.
Smits DW Ketelaar M Gorter JW van Schie PE Becher JG Lindeman E Jongmans MJ 《Journal of intellectual disability research : JIDR》2011,55(6):550-562
Background Children with cerebral palsy (CP) are at greater risk for a limited intellectual development than typically developing children. Little information is available which children with CP are most at risk. This study aimed to describe the development of non‐verbal intellectual capacity of school‐age children with CP and to examine the association between the development of non‐verbal intellectual capacity and the severity of CP. Methods A longitudinal analysis in a cohort study was performed with a clinic‐based sample of children with CP. Forty‐two children were assessed at 5, 6 and 7 years of age, and 49 children were assessed at 7, 8 and 9 years of age. Non‐verbal intellectual capacity was assessed by Raven's Coloured Progressive Matrices (RCPM). Severity of CP was classified by the Gross Motor Function Classification System, type of motor impairment and limb distribution. manova for repeated measurements was used to analyse time effects and time × group effects on both RCPM raw scores and RCPM intelligence quotient scores. Results The development of non‐verbal intellectual capacity was characterised by a statistically significant increase in RCPM raw scores but no significant change in RCPM intelligence quotient scores. The development of RCPM raw scores was significantly associated with the severity of CP. Children with higher levels of gross motor functioning and children with spastic CP showed greater increase in raw scores than children with lower levels of gross motor functioning and children with dyskinetic CP. Conclusions Children with CP aged between 5 and 9 years show different developmental trajectories for non‐verbal intellectual capacity, which are associated with the severity of CP. The development of non‐verbal intellectual capacity in children with less severe CP seems to resemble that of typically developing children, while children with more severe CP show a limited intellectual development compared to typically developing children. 相似文献
59.
60.
目的 探讨T淋巴细胞亚群、可溶性白介素2受体和肿瘤坏死因子α在梅毒发病机制中的作用。方法 应用流式细胞仪和双抗体夹心ELISA法对86例梅毒患者T淋巴细胞亚群(CD3+、CD4+、CD8+)、可溶性白介素2受体(sIL-2R)及肿瘤坏死因子α(TNF-α)水平进行检测,并对其相关性进行分析。结果 梅毒患者CD4+及CD4+/CD8+比值明显低于正常人对照组(P<0.01),CD8+显著高于正常人对照组(P<0.05),而CD3+与正常人对照组无显著性差异(P>0.05);活动期梅毒CD4+/CD8+比值低于恢复期(P<0.05)。活动期梅毒及非活动期梅毒患者血清sIL-2R水平均明显增高(P<0.01),且活动期高于非活动期(P<0.01)。活动期梅毒患者血清TNF-α水平高于非活动期及正常对照组(P<0.01),且活动期高于非活动期(P<0.01)。活动期梅毒患者 CD4+、CD8+与 sIL-2R和 TNF-α水平呈正、负相关。结论 本研究提示梅毒患者存在细胞免疫功能抑制现象,且 T淋巴细胞功能的紊乱和TNF-α及sIL-2R水平的改变与梅毒的发病有密切关系。 相似文献