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991.
992.
The "Mainzer EMF-Wachhund," a watchdog project, offered a system of self-notification of health complaints attributed to exposures to electromagnetic fields (EMFs) to a population of a part of Germany with about 4 million inhabitants. By using a self-administered questionnaire, which was provided online and for download from the Internet, 192 persons reported such health complaints in the period from October 2003 to March 2005. Of these, 56% classified themselves as electromagnetic hypersensitive (EH). Predictors of this self classification were being affected by all kinds of EMF rather than single EMF sources and being female. On average, EH subjects reported a high degree of suffering, 77% of whom had already sought advice from physicians. An Internet-based standardized questionnaire is an economic way of offering affected persons a direct link to scientific institutions to establish contact. However, the study base obtained by such an approach is not representative to estimate a population-based prevalence. As a large number of subjects did not classify themselves as EH and reported very specific links between exposure and symptoms, they may provide a very distinct and interesting group for future research.  相似文献   
993.
994.

Background  

DNA Microarrays have become the standard method for large scale analyses of gene expression and epigenomics. The increasing complexity and inherent noisiness of the generated data makes visual data exploration ever more important. Fast deployment of new methods as well as a combination of predefined, easy to apply methods with programmer's access to the data are important requirements for any analysis framework. Mayday is an open source platform with emphasis on visual data exploration and analysis. Many built-in methods for clustering, machine learning and classification are provided for dissecting complex datasets. Plugins can easily be written to extend Mayday's functionality in a large number of ways. As Java program, Mayday is platform-independent and can be used as Java WebStart application without any installation. Mayday can import data from several file formats, database connectivity is included for efficient data organization. Numerous interactive visualization tools, including box plots, profile plots, principal component plots and a heatmap are available, can be enhanced with metadata and exported as publication quality vector files.  相似文献   
995.
The glycoprotein CD86 is an important costimulatory molecule that has been shown to be predominantly expressed on APCs, such as dendritic cells, macrophages, and B cells. More recently, CD86 was also detected on T cells in specific pathological conditions. The mechanisms of how CD86 might be induced and its functional role in T cells are not well understood. In the present study, we showed that treatment with IL-2 markedly upregulated CD86, but not CD80, in human CD4(+) and CD8(+) T cells. This upregulation occurred in the absence of bystander cells, and isolated naive CD4(+) or CD8(+) T cells exhibited different time-dependent CD86-expression patterns in response to IL-2. Upregulation of CD86 on activated T cells was reduced by Abs that block IL-2 and IL-2Rα (CD25), indicating a receptor-mediated mechanism. IL-2-dependent CD86 upregulation was blocked by pharmacological inhibitors of the NFAT and mammalian target of rapamycin pathways and was largely reduced by simultaneous exposure to IFN-α. Importantly, a marked increase in CD86 on T cells was also observed in vivo in IL-2-treated patients. In conclusion, IL-2 upregulates CD86 expression on human CD4(+) and CD8(+) T cells via a receptor-dependent mechanism that involves the NFAT and mammalian target of rapamycin pathways.  相似文献   
996.
997.
Genetic variation at the TERT-CLPTM1L locus at 5p15.33 is associated with susceptibility to several cancers, including epithelial ovarian cancer (EOC). We have carried out fine-mapping of this region in EOC which implicates an association with a single nucleotide polymorphism (SNP) within the TERT promoter. We demonstrate that the minor alleles at rs2736109, and at an additional TERT promoter SNP, rs2736108, are associated with decreased breast cancer risk, and that the combination of both SNPs substantially reduces TERT promoter activity.  相似文献   
998.
DNA ligase IV (LigIV) deficiency was identified as the molecular basis for a severe form of combined immunodeficiency in two microcephalic siblings with cellular radiosensitivity. In one patient the diagnosis was made directly after birth, allowing analysis of the role of LigIV in the development of specific immune cells. Absolute numbers of B cells were reduced 100-fold and alphabeta T cells 10-fold, whereas gammadelta T cells were normal. Spectratyping of all three cell populations showed a diverse repertoire, but sequencing of IgH V(D)J junctions revealed shorter CDR3 regions due to more extensive nucleotide deletions among D and J elements and fewer N nucleotide insertions. Clonal restriction of IgG-expressing, but not IgM-expressing, B cells and the lack of primary and secondary lymph node follicles indicated impaired class switch recombination. Observations in the older sibling showed that this rudimentary immune system was able to mount specific responses to infection. However, partial Ab responses and extensive amplification of gammadelta T cells could not prevent a life-threatening course of viral and bacterial infections, the development of an EBV-induced lymphoma, and immune dysregulation reflected by severe autoimmune cytopenia. Impaired generation of immune diversity under conditions of limited LigIV activity can cause a human SCID variant with a characteristic immunological phenotype.  相似文献   
999.
Interleukin-6 (IL-6) exerts pro- as well as anti-inflammatory activities in response to infection, injury, or other stimuli that affect the homeostasis of the organism. IL-6-induced expression of acute-phase protein genes in the liver is tightly regulated through both IL-6-induced feedback inhibitors and the activity of pro-inflammatory cytokines such as tumor necrosis factor alpha and interleukin-1beta. In previous studies mechanisms for how IL-1beta counteracts IL-6-dependent acute-phase protein gene induction have been proposed. Herein we analyzed IL-1beta-mediated regulation of IL-6-induced expression of the feedback inhibitor SOCS3. In hepatocytes IL-1beta alone does not induce SOCS3 expression, but it counteracts SOCS3-promoter activation in long term studies. Surprisingly, short term stimulation revealed IL-1beta to be a potent enhancer of SOCS3 expression in concert with IL-6. This activity of IL-1beta does not depend on IL-1beta-dependent STAT1-serine phosphorylation but on NF-kappaB-dependent gene induction. Such a regulatory network allows IL-1beta to counteract IL-6-dependent expression of acute-phase protein genes without inhibiting IL-6-induced SOCS3 expression and provides a reasonable mechanism for the IL-1beta-dependent inhibition of acute-phase gene induction, because reduced SOCS3 expression would lead to enhanced IL-6 activity.  相似文献   
1000.
In ischemic hearts, venous retroperfusion is a potential myocardial revascularization strategy. This study aimed to refine the technical and functional aspects of a pig model of acute myocardial infarction and retroperfusion with respect to the azygos connection. Global retroperfusion after ligation of the ramus interventricularis paraconalis (equivalent to the left anterior descending artery in humans) was performed in 16 Landrace pigs (Sus scrofa domestica). Coronary sinus perfusion was performed in 8 pigs (P+) but not in the other 8 (P–), and the azygos vein was ligated (L+) 4 of the 8 pigs in each of these groups but left open (L–) in the remaining animals. Hemodynamic performance (for example, cardiac output, stroke volume) was significantly better in P+L+ pigs that underwent coronary sinus perfusion with ligation of the azygos vein compared with all other animals. In addition, troponin I release was significant lower in P+L+ pigs (1.7 ± 1.3 ng/mL) than in P–L– (5.47 ± 2.1 ng/mL), P–L+ (6.63 ± 2.4 ng/mL), and P+L– (4.81 ± 2.3 ng/mL) pigs. Effective retrograde flow and thus hemodynamic stability was achieved by ligation of the azygos vein. Therefore, experiments focusing on global retroperfusion will benefit from effective inhibition of the blood flow through the azygos vein.Abbreviations: ACS, aorta-to-coronary–sinus shunt, CS, coronary sinus, L, ligation, LAD, left anterior descending artery, P, perfusionAnimal models are used frequently to investigate myocardial revascularization techniques, and researchers have studied global or selective venous retroperfusion in dogs,22 pigs,9 and sheep.33 The goal underlying retrograde coronary sinus (CS) perfusion is perfusion of the ischemic myocardium proximal to the occlusion or stenosis. This method frequently is used for delivering cardioplegic solutions during cardiac surgery. In addition, both clinical2,3,6,16,28,30 and experimental 11,21,25,34,37,42 studies have validated the efficiency of CS retroperfusion.Interpreting the results from experimental animal models and follow-up examinations of patients who have undergone venous revascularization has led to controversy.9,37 In particular, technical problems with some studies have been identified. Previous animal studies on interspecies anatomic differences in mammals4,7,19 have concentrated on the venous connections of the vessels draining the myocardium and have demonstrated a need for further feasibility studies of the pig model (German Landrace pigs, Sus scrofa domestica) that focus on hemodynamic performance.We wanted to characterize in detail the contribution of the azygos vein connection in swine during retroperfusion after myocardial infarction and hypothesized that ligation of the azygos vein would preserve hemodynamic function after ligation of the left anterior descending artery (LAD) in a global retroperfusion model in pigs.  相似文献   
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