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1.
The topical application of aspirin and omega-3 polyunsaturated fatty acids (PUFAs) may trigger the resolution of inflammation by inducing the biosynthesis of pro-resolvers such as lipoxins and resolvins while also avoiding the side effects of systemic aspirin intake. This study assessed the effect of enhanced granulation tissue (EGT) on periodontal tissue regeneration through the local application of aspirin and omega-3 PUFAs directly to granulation tissue (GT) during periodontal surgery. This randomized controlled experiment assesses 38 pockets in 19 patients. In every patient, two similar intrabony periodontal defects are treated with an open flap debridement, one with EGT (GT extracted, enhanced with aspirin and omega-3 PUFAs, and replaced) and the other with standard GT removal. Clinical attachment level (CAL) and probing pocket depth (PPD) are assessed at baseline and 2 and 6 months after surgery. The experimental protocol (EGT) results in a greater CAL gain as compared to that in the controls at 6 months (p < 0.05), while PPD reduction is not affected. The retained GT does not compromise healing. EGT is proposed as a promising, inexpensive, and simple method that may improve the outcome of periodontal regenerative treatment. However, the described protocol requires optimization and further assessment. Practical Applications : The biosynthesis of mediators including resolvins and lipoxins triggered by aspirin and omega-3 PUFAs promote the resolution of inflammation, eventually leading to faster regeneration of inflamed tissues. While granulation tissue is a necessary component in wound healing, enhancing granulation tissue with aspirin and omega-3 PUFAs results in CAL gain in the surgical treatment of periodontal defects. Retained granulation tissue does not compromise periodontal healing. The EGT strategy is an inexpensive and simple method that may improve the clinical outcomes of regenerative periodontal procedures.  相似文献   
2.
Deregulated melanogenesis is involved in melanomagenesis and melanoma progression and resistance to therapy. Vitamin D analogs have anti-melanoma activity. While the hypercalcaemic effect of the active form of Vitamin D (1,25(OH)2D3) limits its therapeutic use, novel Vitamin D analogs with a modified side chain demonstrate low calcaemic activity. We therefore examined the effect of secosteroidal analogs, both classic (1,25(OH)2D3 and 25(OH)D3), and novel relatively non-calcemic ones (20(OH)D3, calcipotriol, 21(OH)pD, pD and 20(OH)pL), on proliferation, colony formation in monolayer and soft-agar, and mRNA and protein expression by melanoma cells. Murine B16-F10 and hamster Bomirski Ab cell lines were shown to be effective models to study how melanogenesis affects anti-melanoma treatment. Novel Vitamin D analogs with a short side-chain and lumisterol-like 20(OH)pL efficiently inhibited rodent melanoma growth. Moderate pigmentation sensitized rodent melanoma cells towards Vitamin D analogs, and altered expression of key genes involved in Vitamin D signaling, which was opposite to the effect on heavily pigmented cells. Interestingly, melanogenesis inhibited ligand-induced Vitamin D receptor translocation and ligand-induced expression of VDR and CYP24A1 genes. These findings indicate that melanogenesis can affect the anti-melanoma activity of Vitamin D analogs in a complex manner.  相似文献   
3.
测井新技术在四川油气勘探开发中的应用   总被引:1,自引:0,他引:1  
综述随着四川盆地油气勘探深入所面临的油气领域复杂和困难的技术问题,介绍应用测井新技术为四川油气开发解决了大量的技术难题,特别是在复杂缝,洞型储层的评价,井旁地质构造形态精细分析和地质,测井,地震多学科结合储层横向预测等3个方面所取得的良好应用效果。  相似文献   
4.
We report on a single‐layer organic memory device made of poly(N‐vinylcarbazole) embedded between an Al electrode and ITO modified with Ag nanodots (Ag‐NDs). Devices exhibit high ON/OFF switching ratios of 104. This level of performance could be achieved by modifying the ITO electrodes with some Ag‐NDs that act as trapping sites, reducing the current in the OFF state. Temperature dependence of the electrical characteristics suggest that the current of the low‐resistance state can be attributed to Schottky charge tunnelling through low‐resistance pathways of Al particles in the polymer layer and that the high‐resistance state can be controlled by charge trapping by the Al particles and Ag‐NDs.  相似文献   
5.
Object orientation and formal methods are widely regarded as two fields with significant potential for new software engineering techniques. This paper discusses the relations between these two approaches. We present various specification techniques which incorporate object-oriented paradigms, discuss their place in software development process, and analyse possible benefits from their applications.  相似文献   
6.
Genomic signal processing (GSP) concerns the processing of genomic signals. It may be defined as the analysis, processing, and use of genomic signals to gain biological knowledge and the translation of that knowledge into systems-based applications. In this article, the authors discuss the key research issues for GSP. It is important to recognize that "genomic signal processing" is not a name for genomic bioinformatics nor for the application of signal processing methods in genomics. We note that the research issues pertaining to GSP fit within the overall challenges confronting research in the area of multimodal biomedical systems.  相似文献   
7.
In this paper, mobility parameters for enhancement-mode N-channel 4H SiC MOSFETs are extracted and implemented into 2-D device simulation program and SPICE circuit simulator. The experimental data were obtained from lateral N-channel 4H SiC MOSFETs with nitrided oxide–semiconductor interfaces, exhibiting normal mobility behavior. The presence of increasing interface-trap density (Dit) toward the edge of the conduction band is included during the 2-D device simulation. Using measured distribution of interface-trap density for simulation of the transfer characteristics leads to a good agreement with the experimental transfer characteristic.  相似文献   
8.
To identify possible sources of the observed differences in the career choices of women and men, three facets of career preferences were examined: the relative importance attributed to career-related aspects, the within-aspect preferences (i.e., desirable characteristics of occupations), and the structure of aspects derived from these within-aspect preferences. The career-related preferences of 2,000 young adults who were in the process of making their career decisions were analyzed. These career-related preferences were elicited during their dialogues with a computer-assisted career guidance system. The analyses revealed (a) only small gender differences in the relative importance of the aspects, (b) considerable gender differences in the within-aspect preferences, and (c) certain gender differences in the structure of aspects. The findings and their possible theoretical and practical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
10.
By comparing the experimental data of the Sauter-mean-diameter d 32 and the hold up ? with models from literature, there are presented equations for d 32 and ? for the used conical turbine in gas-liquid systems. The necessary adjustment of the proportionality constants of the literature equations will be explained on the basis of fluiddynamical phenomena. It can be established by fluid-dynamical results of a former study carried out with laser-doppler-anemometry. Coalescence phenomena are taken into account in the model using an analogy to bubble columns. The analogy to bubble columns turns out to be suitable. Arguments for the necessity of considering the local fluiddynamics in the modelling of dispersions are presented.  相似文献   
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