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排序方式: 共有601条查询结果,搜索用时 31 毫秒
1.
Claudia Trenkwalder MD Heike Benes MD Ludger Grote MD Svenja Happe MD Birgit Högl MD Johannes Mathis MD Gerda M. Saletu‐Zyhlarz MD Ralf Kohnen PhD CALDIR study group 《Movement disorders》2007,22(5):696-703
We report the first large-scale double-blind, randomly assigned study to compare two active dopaminergic therapies for Restless Legs Syndrome (RLS), the dopamine agonist cabergoline (CAB) and levodopa/benserazide (levodopa). Patients with idiopathic RLS were treated with fixed daily doses of 2 or 3 mg CAB or 200 or 300 mg levodopa for 30 weeks. Efficacy was assessed by changes in the IRLS (International RLS Severity Scale) and by time to discontinuation of treatment due to loss of efficacy or augmentation. 361 of 418 screened patients (age 58 +/- 12 years, 71% females) were randomly assigned and treated (CAB: n = 178; levodopa: n = 183) in 51 centers of four European countries. Baseline IRLS total score was 25.7 +/- 6.8. The baseline-adjusted mean change from baseline to week 6 in IRLS sum score was d = -16.1 in the CAB group and d = -9.5 in the levodopa group (d = -6.6, P < 0.0001). More patients in the levodopa group (24.0%) than in the CAB group (11.9%, P = 0.0029, log-rank test) discontinued because of loss of efficacy (14.2% vs. 7.9%, P = 0.0290) or augmentation (9.8% vs. 4.0%, P = 0.0412). Adverse events (AEs) occurred in 83.1% of the CAB group and in 77.6% of the levodopa group. In both groups, most frequent AEs were gastrointestinal symptoms (CAB: 55.6%, levodopa: 30.6%, P < 0.0001). This first large-scale active controlled study in RLS showed superior efficacy of cabergoline versus levodopa after a 30-week long-term therapy. Tolerability was found more favorable with levodopa than with cabergoline. 相似文献
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Immunity against Eimeria-infections is highly specific and it depends on cell-mediated effector mechanisms. Infections of BALB/c mice with 1000 sporulated oocysts of Eimeria falciformis led to protection against challenge infections. Treatment with the anticoccidium Toltrazuril, during primary infection, terminated the ongoing disease and did not interfere with the establishment of protective immunity against challenge infections. Mesenteric lymph node cells of infected, treated as well as non-treated and challenged BALB/c mice, showed a similar proliferation upon stimulation with parasite antigen. In contrast, neither cells of the Peyers patches, intraepithelial lymphocytes, nor spleen cells responded to stimulation with parasite antigens. Cells from all compartments and of all investigated groups proliferated and released the cytokines IFN- and IL-4 in response to the mitogen Concanavalin A. The number of cells releasing IFN- or IL-4 was not dependent on the status of infection or previous treatment with Toltrazuril. The serum IgG response against total sporozoite antigens of individual mice showed that in addition, a systemic humoral response developed in infected mice, independent of a previous drug treatment, although the specific IgG antibody concentration was higher in non-treated mice. Thus, Toltrazuril does not impair the parasite specific intestinal cellular and systemic antibody response and does not prevent the development of protection against challenge infection. 相似文献
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OBJECTIVE: Because of the wide dissemination of malignant glioma cells by the time that malignant glioma is diagnosed, anti-invasive strategies that are designed to limit their further spread may be of little value unless mechanisms of the invasive cascade can be used to render invasive cells susceptible to cytoreductive treatments. We recently determined that elevated thromboxane synthase gene expression and enzymatic activity are associated with a highly migratory phenotype of glioma cells in vitro and that specific inhibitors of this enzyme block cell migration. Interference with this inherent phenotype of malignant gliomas also affects glioma cell proliferation and apoptosis. METHODS: To study the effect of thromboxane synthase inhibitors on motility, metabolic activity, and cell death, we used five human glioma cell lines, four glioblastoma-derived, low-passage cell cultures, normal human astrocytes, and fibroblasts. Motility was measured in a monolayer migration assay. Caspase activation as an early event in apoptotic cell death was assessed using a caspase 3 cleavage assay. Intracellular deoxyribonucleic acid (DNA) fragmentation was detected by enzyme-linked immunosorbent assay quantification of histone-complexed DNA. Subsequent cell death was scored by trypan blue exclusion. RESULTS: In this study, we demonstrate that the treatment of human glioma cells with the specific thromboxane synthase inhibitor furegrelate leads first to caspase activation (detectable 6 h after treatment), then to DNA fragmentation (24-48 h after treatment) and subsequent cell death. Caspase inhibitors abrogate this effect. Furthermore, the inhibition of thromboxane synthase by furegrelate increases cells' susceptibility to the induction of DNA fragmentation by camptothecin, etoposide, N,N'-bis(2-chloroethyl)-N-nitrosourea, and anti-CD95 antibodies. No induction of apoptosis was observed in normal astrocytes and fibroblasts. CONCLUSION: These data indicate that thromboxane synthase may represent a vortex of divergent signaling cascades that regulate motility and apoptosis in glioma cells. This paradigm may offer a novel perspective in the treatment of patients with malignant gliomas. 相似文献
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Reduced frequencies and suppressive function of CD4+CD25hi regulatory T cells in patients with chronic lymphocytic leukemia after therapy with fludarabine 总被引:20,自引:3,他引:20 下载免费PDF全文
Beyer M Kochanek M Darabi K Popov A Jensen M Endl E Knolle PA Thomas RK von Bergwelt-Baildon M Debey S Hallek M Schultze JL 《Blood》2005,106(6):2018-2025
Globally suppressed T-cell function has been described in many patients with cancer to be a major hurdle for the development of clinically efficient cancer immunotherapy. Inhibition of antitumor immune responses has been mainly linked to inhibitory factors present in cancer patients. More recently, increased frequencies of CD4+CD25hi regulatory T cells (Treg cells) have been described as an additional mechanism reducing immunity. We assessed 73 patients with B-cell chronic lymphocytic leukemia (CLL) and 42 healthy controls and demonstrated significantly increased frequencies of cytotoxic T lymphocyte-associated protein 4 (CTLA4+)-, Forkhead box P3 (FOXP3+)-, glucocorticoid-induced tumor necrosis factor receptor-related protein (GITR+)-, CD62L+-, transforming growth factor beta1 (TGF-beta1+)-, interleukin 10 (IL-10+)-Treg cells in patients with CLL, with highest frequencies in untreated or progressing patients presenting with extended disease. Most surprisingly, in the majority of patients with CLL treated with fludarabine-containing therapy regimens the inhibitory function of Treg cells was decreased or even abrogated. In addition, frequencies of Treg cells were significantly decreased after therapy with fludarabine. In light of similar findings for cyclophosphamide the combination of fludarabine and cyclophosphamide might be further exploited in strategies reducing immunosuppression prior to cancer immunotherapy. 相似文献
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Svenja M. Spuling Verena Klusmann Catherine E. Bowen Anna E. Kornadt Eva-Marie Kessler 《European journal of ageing》2020,17(4):445
Although a large body of research has demonstrated the predictive power of subjective ageing for several decisive developmental outcomes, there remains some controversy about whether subjective ageing truly represents a unique construct. Thus, information about the convergent and discriminant validity of different approaches to measuring subjective ageing is still critically needed. Using data from the 2014 wave of the German Ageing Survey, we examined how three established subjective ageing measures (subjective age, global attitude toward own ageing, multidimensional ageing-related cognitions) were inter-related as well as distinct from general dispositions (optimism, self-efficacy) and well-being (negative affect, depressive symptoms, self-rated health). Using correlational and multivariate regression analysis, we found that the three subjective ageing measures were significantly inter-related (r = |.09| to |.30|), and that each measure was distinct from general dispositions and well-being. The overlap with dispositional and well-being measures was lowest for subjective age and highest for global attitudes towards own ageing. The correlation between global attitudes towards own ageing and optimism was particularly striking. Despite the high convergent validity of the different dimensions of ageing cognitions, we nevertheless observed stronger associations between specific dimensions of ageing cognitions with negative affect and self-rated health. We conclude that researchers should be aware of the multidimensional nature of subjective ageing. Furthermore, subjective age appears to be a highly aggregated construct and future work is needed to clarify its correlates and reference points.Electronic supplementary materialThe online version of this article (10.1007/s10433-019-00529-7) contains supplementary material, which is available to authorized users. 相似文献
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Michael Stimmelmayr Jan-Frederik Güth Kurt Erdelt Arndt Happe Markus Schlee Florian Beuer 《Clinical oral investigations》2013,17(8):1929-1935
Objectives
Precise implant-supported prosthodontics requires accurate impressions. Many in vitro studies comparing different implant impression techniques were performed. The purpose of this in vivo study was to compare the discrepancy of two different impression techniques of implants clinically.Material and methods
Four implants were inserted nearly bilateral in ten edentulous jaws. From each jaw, two different impressions (A, transfer; B, splinted pick-up) were taken. Respectively two stone casts of each jaw were produced and scan bodies were mounted on the lab analogues to digitize the casts. One scan body of the digitized casts was each superimposed and the deviations of the remaining three scan bodies were measured three dimensionally. The fit of the suprareconstructions was evaluated clinically on both casts and in the mouth.Results
The mean discrepancy of scan body 2 was 192 μm (±96), 282 μm (±97) for scan body 3, and 366 μm (±114) for scan body 4. The discrepancies between two scan bodies were statistically significant (p?≤?0.010; ANOVA test). Comparing the data with the span between the scan bodies, a linear regression line could be drawn to show the dependency between the misfit and the length of the span. Clinically, the fit on the cast produced by the splinted pick-up technique was favorable.Conclusions
The discrepancy between the splinted pick-up impression technique and the transfer technique were in a range with clinical influence.Clinical relevance
For better accuracy of implant-supported prosthodontics, the splinted pick-up technique should be used for impressions of four implants evenly spread in edentulous jaws. 相似文献10.
Breloer M Kretschmer B Lüthje K Ehrlich S Ritter U Bickert T Steeg C Fillatreau S Hoehlig K Lampropoulou V Fleischer B 《European journal of immunology》2007,37(3):634-648
The transmembrane glycoprotein CD83 has been described as a specific maturation marker for dendritic cells and several lines of evidence suggest that CD83 regulates thymic T cell maturation as well as peripheral T cell activation. Here we show for the first time that CD83 is involved also in the regulation of B cell function. CD83 is up-regulated on activated B cells in vivo, specifically in the draining lymph nodes of Leishmania major-infected mice. The ubiquitous transgenic (Tg) expression of CD83 interferes with Leishmania-specific T cell-dependent and with T cell-independent antibody production. This defect is restricted to the B cell population since the antigen-specific T cell response of CD83Tg mice to L. major infection is unchanged. The defective immunoglobulin (Ig) response is due to Tg expression of CD83 on the B cells because wild-type B cells display normal antigen-specific responses in CD83Tg hosts and CD83Tg B cells do not respond to immunization in a mixed wild-type/CD83Tg bone marrow chimera. Finally, the treatment of non-Tg C57BL/6 mice with anti-CD83 mAb induces a dramatic increase in the antigen-specific IgG response to immunization, thus demonstrating a regulatory role for naturally induced CD83 on wild-type B cells. 相似文献