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51.
The presence of IgE on macrophages and dendritic cells infiltrating into the skin lesion of atopic dermatitis 总被引:7,自引:0,他引:7
D Y Leung E E Schneeberger R P Siraganian R S Geha A K Bhan 《Clinical immunology and immunopathology》1987,42(3):328-337
Monoclonal antibodies reactive with human IgE were used to investigate the presence of surface IgE in situ on mononuclear cells infiltrating into the skin lesion of atopic dermatitis (A.D.) by application of the immunoperoxidase technique to tissue sections for light and electron microscopic examination. A substantial proportion of infiltrating macrophages but not of lymphocytes were found to bear IgE on their cell surfaces. These observations raise the possibility that IgE may contribute to the skin inflammation associated with A.D. via non-mast-cell-mediated immune mechanisms. We hypothesize that allergens introduced into the skin lesion of A.D. are potentially capable of interacting not only with IgE-bearing mast cells but also with IgE-bearing macrophages and dendritic cells to cause the release of inflammatory mediators. 相似文献
52.
Dirschka T Radny P Dominicus R Mensing H Brüning H Jenne L Karl L Sebastian M Oster-Schmidt C Klövekorn W Reinhold U Tanner M Gröne D Deichmann M Simon M Hübinger F Hofbauer G Krähn-Senftleben G Borrosch F Reich K Berking C Wolf P Lehmann P Moers-Carpi M Hönigsmann H Wernicke-Panten K Helwig C Foguet M Schmitz B Lübbert H Szeimies RM;AK-CT Study Group 《The British journal of dermatology》2012,166(1):137-146
Background Photodynamic therapy (PDT) with 5‐aminolaevulinic acid (ALA) or its methylester [methyl‐5‐aminolaevulinate (MAL) or 5‐amino‐4‐oxopentanoate] was recently ranked as first‐line therapy for the treatment of actinic keratosis (AK) and is an accepted therapeutic option for the treatment of neoplastic skin diseases. BF‐200 ALA (Biofrontera Bioscience GmbH, Leverkusen, Germany) is a gel formulation of ALA with nanoemulsion for the treatment of AK which overcomes previous problems of ALA instability and improves skin penetration. Objectives To evaluate the efficacy and safety of PDT of AKs with BF‐200 ALA in comparison with a registered MAL cream and with placebo. Methods The study was performed as a randomized, multicentre, observer‐blind, placebo‐controlled, interindividual trial with BF‐200 ALA, a registered MAL cream and placebo in a ratio of 3 : 3 : 1. Six hundred patients, each with four to eight mild to moderate AK lesions on the face and/or the bald scalp, were enrolled in 26 study centres in Germany, Austria and Switzerland. Patients received one PDT. If residual lesions remained at 3 months after treatment, PDT was repeated. Results PDT with BF‐200 ALA was superior to placebo PDT with respect to patient complete clearance rate (78·2% vs. 17·1%; P < 0·0001) and lesion complete clearance rate (90·4% vs. 37·1%) at 3 months after the last PDT. Moreover, superiority was demonstrated over the MAL cream regarding the primary endpoint patient complete clearance (78·2% vs. 64·2%; P < 0·05). Significant differences in the patient and lesion complete clearance rates and severity of treatment‐related adverse events were observed for the narrow‐ and broad‐spectrum light sources. Conclusions BF‐200 ALA is a very effective, well‐tolerated new formulation for AK treatment with PDT and is superior to a registered MAL medication. Efficacies and adverse events vary greatly with the different light sources used. 相似文献
53.
青年学者常常在完成资料收集和分析之后对获得的结果充满了激情。然而,在开始写作论文时,这种热情常常锐减。事实也如此,国家级学术会议的论文数远高于最终发表的医学文献数。优秀的研究成果不能发表的原因2大多在于写作新手在开始写作时对写作的认识混乱和畏缩。一般产生畏缩的原因有2个:要么是研究者不知从何着手,要么是不知如何组织文章结构。不过,大部分放射学论文的写作均有规律可寻,在很大程度上是程式化的。本文试图介绍一种可应用于典型放射学论文的逐段写作法。如果初学者能够完成按照本文教授的18段写作,其论文将具有合理的结构,… 相似文献
54.
Celiac disease (CD) follows an autoimmune course in which both genetic and environmental factors contribute to its development. A strong association with HLA class II molecules, predominantly HLA-DQ2, has been reported in most ethnic groups with CD. The aim of this study was to determine if genetic polymorphisms in L-selectin, E-selectin, and intercellular adhesion molecule-1 (ICAM-1) have any correlation with CD. We investigated 5 mutations, namely F206L in L-selectin, S128R and L554F in E-selectin, and G241R and K469E in ICAM-1, in 37 North Indian pediatric patients with CD. A significant increase in allele frequencies of 128R of E-selectin and the associated genotype SR was observed in patients. No significant differences were observed in the F206L polymorphism of L-selectin, or the G241R and E469K polymorphisms in the ICAM-1 gene in CD. This study illustrates that selectin gene polymorphism might contribute to the genetic background of CD and invites further investigation relevant to understanding the mechanisms underlying the immunopathogenesis of this autoimmune disease. 相似文献
55.
Blocking inducible co-stimulator in the absence of CD28 impairs Th1 and CD25+ regulatory T cells in murine colitis 总被引:4,自引:0,他引:4
de Jong YP Rietdijk ST Faubion WA Abadia-Molina AC Clarke K Mizoguchi E Tian J Delaney T Manning S Gutierrez-Ramos JC Bhan AK Coyle AJ Terhorst C 《International immunology》2004,16(2):205-213
Several autoimmune disease models depend on an imbalance in the activation of aggressor T(h)1 and CD4(+)CD25(+) regulatory T (T(reg)) cells. Here we compare the requirement for signals through the co-stimulatory molecules CD28 and inducible co-stimulator (ICOS) in chronic murine colitis, a model for inflammatory bowel disease. We used a colitis model in which disease-causing CD45RB(hi) T cells alone or in combination with CD4(+)CD25(+) T cells from either CD28-deficient or wild-type donors were transferred into T cell-deficient animals, half of which were treated with ICOS-blocking reagents. Blocking ICOS on the surface of CD28-deficient T(h)1 cells abrogated development of colitis, whereas blocking CD28 or ICOS alone had little to no effect on disease induction. In contrast to T(h)1 cells, regulatory T cell functioning depended mostly on CD28 signaling with only a minor contribution for ICOS. We conclude that CD28 and ICOS collaborate to development of murine colitis by aggressor T(h)1 cells, and that CD28 is required for T(reg) cells, which should caution against the use of CD28-blocking reagents in inflammatory bowel disease. 相似文献
56.
Identification and characterization of CS20, a new putative colonization factor of enterotoxigenic Escherichia coli. 总被引:1,自引:0,他引:1 下载免费PDF全文
An enterotoxigenic Escherichia coli (ETEC) strain producing a previously undescribed putative colonization factor was isolated from a child with diarrhea in India. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of bacterial heat extracts revealed a polypeptide band of 20.8 kDa when the bacteria were grown at 37 degrees C which was absent after growth at 22 degrees C. A specific rabbit antiserum raised against the purified 20.8-kDa protein bound specifically to the fimbriae, as shown by immunoelectron microscopy, and inhibited bacterial adhesion to tissue-cultured Caco-2 cells. Transformation with a recombinant plasmid harboring the cfaD gene, which encodes a positive regulator for several ETEC fimbriae, induced hyperexpression of the 20.8-kDa fimbrial subunit and a substantial increase in the proportion of bacterial cells that were fimbriated. The N-terminal amino acid sequence of the polypeptide showed 65 and 60% identity to the PCFO20 and 987P fimbriae of human and porcine ETEC, respectively. We propose the term CS20 for this new putative colonization factor of human ETEC. 相似文献
57.
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59.
Objectives
To analyze the concept of “case series” in the medical literature compared with case reports.Methods
A PubMed search for articles published during 2009 which had “case series” in their title was performed. A total number of 621 articles were retrieved. 586 papers were included in the analysis and 35 were excluded (18 were commentary letters, 5 were not in English, and twelve could not be retrieved by our Library). The number of patients and category of these articles were analyzed.Results
The median (range) of the number of cases of articles having “case series” in their title was 7 (1–6432) cases. 186/ 586 articles had less than 5 cases (31.7%, 95% CI (28.3–35.1%)). The median (range) of the number of cases of articles having “case report” as their publication type was 4 (1–178) cases. Out of the 219 articles categorized as case reports 114 (52.1%, 95% CI (45.6–58.6%)) had less than five cases.Conclusions
The concept of “case series” is not well defined in the literature and does not reflect a specific research design. We suggest that a case series should have more than four patients while four paitents or less should be reported individually as case reports. 相似文献60.
Azabdaftari G Alroy J Banner BF Ucci A Bhan I Cheville JC 《Pathology, research and practice》2008,204(10):719-723
Metanephric adenoma is a benign renal neoplasm with morphologic features similar to those of malignant renal neoplasms, such as papillary renal cell carcinoma (RCC) and Wilms' tumor. Different methods have been used to distinguish between metanephric adenoma and papillary RCC and Wilms' tumor. However, some techniques are not always available, such as certain immunohistochemical stains, cytogenetics, molecular genetics, and electron microscopy. In the current study, we compared the expression of S100 protein in 15 cases of metanephric adenoma, 10 cases of Wilms' tumor, and 13 cases of papillary RCC. Our results revealed strong expression of S100 proteins in all cases of metanephric adenoma, weak expression in two cases of Wilms' tumor, and no expression in any of the cases of papillary RCC. These findings indicate that S100 could be a useful and accessible tool for the diagnosis of metanephric adenoma. 相似文献