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排序方式: 共有889条查询结果,搜索用时 15 毫秒
1.
Ouédraogo Dieu-Donné Tiendrébéogo Wendlassida Joelle Stéphanie Kaboré Fulgence Ntsiba Honoré 《Clinical rheumatology》2020,39(7):2069-2075
Clinical Rheumatology - Since December 2019, the pandemic caused by coronavirus disease 2019 (COVID-19) raises a real public health problem. COVID-19 appeared in Wuhan (Hubei province) in China.... 相似文献
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F Laffitte J P Chavoin P Guedj D Rouge M Costagliola 《Annales de chirurgie plastique et esthétique》1989,34(5):433-437
The authors present their experience of the use of carbon dioxide laser for the treatment of angiodysplasias (so-called "cavernous" angiomas). The reduction of operative haemorrhage and the simpler postoperative course resulting from the intraoperative and postoperative use of this technique have ensured very satisfactory results in a series of 76 patients. The limitations of the technique are defined. The authors also discuss the complex classification of "cavernous angiomas" and propose a synthetic clinical approach by combining the embryological, histological, evolutive and radiographic features of these lesions. 相似文献
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Lack of a role of cytotoxic necrotizing factor 1 toxin from Escherichia coli in bacterial pathogenicity and host cytokine response in infected germfree piglets
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Ludwig Wilkens Joelle Tchinda Dagmar Burkhardt Hans Heinrich Kreipe 《Pathobiology》2002,70(4):204-208
OBJECTIVE: Comparative genomic hybridization (CGH) has been established as an informative technique in genetic analysis. However, differences in the ratio of hybridization intensities were reported for particular chromosomes, which may affect CGH results. The aim of this study was to define these differences in more detail. For this purpose, CGH results of 70 samples of bone marrow cells (BMC) with normal karyotype in conventional cytogenetics (CC) were evaluated using seven different reference DNAs and two different DNA labeling systems. METHODS AND RESULTS: CGH using fluorochrome-conjugated nucleotides for DNA labeling indicated signal deviations in 21/70 BMC samples. Deviations affected chromosomes 1 (n = 21), 2 (n = 11), 4 (n = 11), 5 (n = 9), 6 (n = 7), 7 (n = 2), 8 (n = 2), 12 (n = 5), 13 (n = 15), 14 (n = 1), 16 (n = 17), 17 (n = 11), 19 (n = 21), 20 (n = 12), and/or 22 (n = 17). None of the imbalances were confirmed by fluorescence in situ hybridization (FISH). Using digoxigenin and biotin-conjugated nucleotides in exemplary cases (n = 5) led to the disappearance of the signal deviations. Repeated CGH experiments using seven different reference DNAs showed remarkable variations in the signal deviations. CONCLUSION: Hybridization differences depend not only on the hapten or fluorochrome-labeled nucleotides used for DNA labeling, but also on the reference DNA chosen. Therefore, close control of CGH experiments is mandatory, and additional techniques such as FISH should be performed to confirm the results obtained by CGH. 相似文献
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We have investigated the density of peptides required to elicit different biological responses in cytotoxic T lymphocytes (CTL), including trogocytosis (i.e., the phenomenon whereby the lymphocytes actively capture fragments of plasma membrane from those cells with which they establish an immune synapse). We have used two separate mouse models of CTL recognising defined peptides presented by MHC class I molecules. In both systems, triggering of cytotoxicity and capture of membrane components reached saturation with low densities of ligand. On the other hand, down-modulation of cell-surface levels of TCR, induction of IFN-gamma production and detection of peptide captured required much higher ligand densities. Interestingly, fratricide (i.e., killing between CTL sharing the same specificity), a mechanism proposed to account for CTL exhaustion, was detected only at antigen concentrations still well above that second threshold leading to full blown activation. Taken together, our results show that the different thresholds that govern the elicitation of different CTL functions correlate with different proportions of antigen among the target cell components being captured via trogocytosis. 相似文献
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Heather A. Pines Pamina M. Gorbach Robert E. Weiss Kristen Hess Ryan Murphy Terry Saunders Joelle Brown Peter A. Anton Ross D. Cranston 《AIDS and behavior》2013,17(3):1002-1015
We assessed the acceptability of three of over-the-counter products representative of potential rectal microbicide (RM) delivery systems. From 2009 to 2010, 117 HIV-uninfected males (79 %) and females (21 %) who engage in receptive anal intercourse participated in a 6-week randomized crossover acceptability trial. Participants received each of three products (enema, lubricant-filled applicator, suppository) every 2 weeks in a randomized sequence. CASI and T-ACASI scales assessed product acceptability via Likert responses. Factor analysis was used to identify underlying factors measured by each scale. Random effects models were fit to examine age and gender effects on product acceptability. Three underlying factors were identified: Satisfaction with Product Use, Sexual Pleasure, and Ease of Product Use. For acceptability, the applicator ranked highest; however, differences between product acceptability scores were greatest among females and younger participants. These findings indicate that RM delivery systems impact their acceptability and should be considered early in RM development to enhance potential use. 相似文献