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71.
Background: A novel member of the interleukin (IL)‐12 family, IL‐35 is an important inhibitory cytokine released by regulatory T cells. The aim of this study is to evaluate gingival crevicular fluid (GCF), saliva, and plasma levels of IL‐35 in periodontal disease and health. Methods: Samples of GCF, whole saliva, and plasma were obtained from systemically healthy, non‐smoking individuals with gingivitis (n = 20) or chronic periodontitis (CP) (n = 20) and periodontally healthy individuals (n = 20). Full‐mouth clinical periodontal measurements, including probing depth (PD), bleeding on probing, gingival index, and plaque index (PI), were also recorded. Enzyme‐linked immunosorbent assay was used to determine IL‐35 levels in the samples. Data were tested statistically by analysis of variance and Pearson rank correlation test. Results: All clinical parameters were significantly higher in the CP group than the healthy and gingivitis groups (P <0.001). The GCF total amount of IL‐35 was significantly higher in the CP group than the other groups (P = 0.04), whereas the GCF concentration of IL‐35 was significantly higher in the healthy group than the other groups (P = 0.002). There were significant differences among the study groups in terms of salivary IL‐35 level (P <0.001), with the highest level observed in the healthy group and the lowest in the CP group. There was no statistical difference between groups in plasma levels of IL‐35 (P >0.05). There was a positive correlation between GCF total amount of IL‐35 and PD (r = 0.338, P = 0.03) and PI (r = 0.374, P = 0.005) parameters. Conclusions: IL‐35 could have an important role in suppressing periodontal inflammation and maintaining periodontal health. Additional studies are required to evaluate its role in periodontal diseases.  相似文献   
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BACKGROUND/AIMS: Combined hepatocellular-cholangiocarcinoma (HCC-CC) show dual hepatocellular and biliary epithelial differentiation. To better understand the relations between cholangiocarcinoma (CC), HCC-CC and hepatocellular carcinoma (HCC), we screened for genetic alterations. METHODS: A series of nine CC, 15 HCC-CC and three separated HCC and CC lesions ('collision tumors') were screened for loss of heterozygosity (LOH) using 400 microsatellite markers and for p53 and beta-catenin mutations. A comparison with a previously characterized series of 137 HCC was performed. RESULTS: In six cases of CC and HCC-CC, we identified TP53 gene mutations. A CTNNB1/beta-catenin was identified in two patients presenting collision tumors, but no mutations were found in CC or in HCC-CC. A high level of chromosome instability in both CC and HCC-CC was found. Recurrent specific LOH were identified at 3p and 14q in more than 50% of the CC and the HCC-CC cases, whereas these chromosomal regions were deleted in less than 10% of the HCC cases (P<10(-5)). Minimal common regions of deletion (MCRD) were defined at 3p24-p14 and 14q24-q32, respectively. CONCLUSIONS: These results suggest that combined HCC-CC are genetically closer to CC than HCC and common carcinogenesis pathways may be altered in HCC-CC and CC.  相似文献   
74.

PURPOSE

The aim of this study was to evaluate whether the push-out bond strength varies between oval and circular fiber posts, and to examine the effect on the resin cement thicknesses around the posts.

MATERIALS AND METHODS

Eighteen mandibular premolar roots were separated into two groups for oval and circular fiber posts systems. Post spaces were prepared and fiber posts were luted to the post spaces. Roots were cut horizontally to produce 1-mm-thick specimens. Resin cement thicknesses were determined with a metallographic optical microscope and push-out tests were done.

RESULTS

No significant differences were observed in terms of push-out bond strength between the oval and circular fiber posts (P>.05) The resin cement thicknesses of the oval posts were greater than those of the circular posts group in the coronal, middle and apical specimens (P<.05).

CONCLUSION

In the light of these results, it can be stated that resin cement thickness does not affect the push-out bond strength.  相似文献   
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The phonation process of vertebrates is influenced by the material characteristics of the participating structures, ranging from molecular to macroscopic dimensions. Good animal models for phonation research are still lacking. Due to easy availability and relatively simple structure, the syrinx of birds might serve as a good animal model for this purpose. Our aim was therefore to determine structural features of the syrinx and obtain insights into its mucus layer characteristics. Epithelium and glands were analyzed using histological, histochemical, and immunohistochemical methods and conclusions were drawn on the use of the syrinx as a model for phonation research by comparing the epithelium and its mucus characteristics to human laryngeal secretions. Ten adult partridges were analyzed. The tympanum of the syrinx developed from the last two tracheal cartilages, whereas the caudal part of the syrinx was formed from eight pieces of bronchial cartilages. The tracheal and bronchial epithelia and the pessulus of the syrinx were lined by pseudo‐stratified columnar epithelium in which goblet cells and intraepithelial glands were localized. Collagen fibers were distributed in the lamina propria of all parts of the syringeal mucosa. Elastic fibers in the membranes of the syrinx showed evident distribution. All glandular epithelial cells and goblet cells were positive for neutral, acidic and carboxylated mucins were dominant in particular. Epithelium and glands revealed positive reactivity with antibodies to the mucins MUC1, MUC2, and MUC5AC. Of these, MUC2 and MUC5AC were dominant. The syrinx of partridge can serve as a good ex vivo model for phonation research. Anat Rec, 298:602–617, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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This article describes a chitosan–collagen composite membrane as corneal tissue-engineering biomaterials. The membrane was prepared by dissolving the chitosan into collagen with the weight ratio of 0, 15, 30, 45, 60, and 100%, followed by crosslinked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. Mechanical properties, contact angles, and optical transmittance were determined and compared between chitosan membrane and crosslinking composite membrane. As a result, the optical transparency and mechanical strength of the chitosan–collagen membranes were significantly better than that of the sample of chitosan. In addition, in vitro cell culture studies revealed that the collagen has no negative effect on the cell morphology, viability, and proliferation and possess good biocompatibility. Overall, the dendrimer crosslinked chitosan–collagen composite membranes showed promising properties that suggest that these might be suitable biomaterials for corneal tissue-engineering applications.  相似文献   
80.
目的:分析并探讨影响接受外科治疗的胸腺瘤患者预后的临床、病理等因素。方法:回顾性分析南京医科大学第一附属医院胸外科2008年1—6月收治的胸腺瘤患者354例,评估分析年龄、性别、肿瘤直径、世界卫生组织(World Health Organization,WHO)病理分型、TNM分期、Masaoka?Koga分期、重症肌无力、根治性切除对患者预后的影响。结果:Kaplan?Meier单因素生存分析显示:年龄(P=0.002)、肿瘤直径(P=0.045)、WHO病理分型(P=0.051)、TNM分期(P=0.004)、Masaoka?Koga分期(P < 0.001)、根治性切除(P < 0.001)与患者预后相关。Cox多因素生存分析显示,年龄(P=0.003,危害比:10.151,95%CI:2.239~46.021)、WHO病理分型(P=0.045,危害比:3.376,95%CI:1.030~11.064)、Masaoka?Koga分期(P=0.009,危害比:5.621,95%CI:1.552~20.352)是影响胸腺瘤患者总体生存的独立预后因素。结论:胸腺瘤的早期诊断可以有效提高其外科治疗效果,积极实行根治性切除是改善胸腺瘤患者预后的重要手段,术后准确的病理分析可帮助临床医生预测患者预后。  相似文献   
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