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Over the last decade, several compounds have been identified for the treatment of obesity. However, due to the complexity of the disease, many pharmacological interventions have raised concerns about their efficacy and safety. Therefore, it is important to discover new factors involved in the induction/progression of obesity. Adipose stromal/stem cells (ASCs), which are mostly isolated from subcutaneous adipose tissue, are the primary cells contributing to the expansion of fat mass. Like other cells, ASCs release nanoparticles known as extracellular vesicles (EVs), which are being actively studied for their potential applications in a variety of diseases. Here, we focused on the importance of the contribution of ASC-derived EVs in the regulation of metabolic processes. In addition, we outlined the advantages/disadvantages of the use of EVs as potential next-generation anti-obesity agents.  相似文献   
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高温抗盐降滤失剂SPX树脂   总被引:4,自引:1,他引:4  
深井和超深井越来越多,对钻井液抗温抗污染能力的要求也越来越高,这样就需要抗高温抗污染的降滤失剂,根据降滤失剂在使用过程中存在的高温增粘和遇到金属离子污染增粘的问题,从研究降滤失剂的分子结构出发,通过苯氧(基)乙酸与苯酚,甲醛发生缩聚反应同时磺化,合成出磺化苯酚/苯氧(基)乙酸/甲醛树脂(简称SPX树脂),室内实验以在180℃下老化16h后的8%二级钠膨胀土钻井液为研究对象,评价了SPX树脂的抗盐性,抗温性,复配性能,高温高压滤失性能及其对表观粘度的影响等,结果表明,SPX树脂单独使用就具有抗饱和盐,抗高温,非增粘降滤失的作用,而且降滤失效果良好,与SMC和SMK有良好的复配效果,SPX树脂已成功地在中国原油田得到应用。  相似文献   
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苏49井是冀中坳陷霸县凹陷文安斜坡信安镇北潜山构造上的一口重点预探井,完钻井深5250 m。针对所钻地层胶结性差,造浆性强,易塌、易漏的特点,上部地层采用正电胶聚合物钻井液体系;下部地层采用聚磺钻井液体系。现场应用表明,这两种钻井液体系性能稳定,抗温性能强,防塌效果好,抑制了玄武岩、煤层的垮塌,保证了取心、电测、下套管及固井施工的顺利进行,全井未发生粘卡事故。  相似文献   
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致密砂岩储集层裂缝综合录井识别技术研究   总被引:6,自引:0,他引:6  
陈清贵  潘小东 《录井工程》2006,17(3):6-9,23
四川盆地油气勘探结果表明,盆地油气储集层普遍为致密砂岩非常规储集层,有效性主要取决于孔、洞、缝发育程度,因此在油气钻井中如何识别致密储集层的孔、洞、缝并确定其所在井段尤其重要。针对综合录井仪的0.1m钻时及相关参数的资料采集技术要求,通过对大量录井数据资料的统计和演算,建立起储集层裂缝发育程度及裂缝发育位置的3种储集层裂缝识别模型,即直接识别模型、地层可钻性(A值)识别模型、钻时回归(RWSR)值识别模型。系统阐述了致密砂岩储集层裂缝综合录井识别技术方法原理,详细介绍了致密砂岩储集层裂缝识别的3个模型在实际生产中的应用情况。该技术方法的研究在国内尚属首次,为油气勘探中储集层评价提供了一个新的方法和手段,可最大限度地发挥现代录井技术在油气勘探开发过程中的作用。  相似文献   
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Farmed European sea bass (Dicentrarchus labrax, Linnaeus, 1758) were collected during 2016 from one Sicilian fish farm that uses two different rearing systems – sea cage and concrete tank – for determination of polychlorinated biphenyls (PCB), organochlorine pesticides (OCP) and polycyclic aromatic hydrocarbons (PAH) residues by HRGC-MS/MS. Moreover, commercial feed was analysed. This study aimed to determine whether the different rearing systems affect the concentration of these compounds, and to assess the safety of cultured fish. PCBs represent the pollutants with the highest concentration; in particular, PCB138 and 153 have the highest concentration in almost all samples. Among OCPs, only 4,4′-DDE, 4,4′-DDD and 4,4′-DDT residues have been detected. Concerning PAHs, only fluorene and phenanthrene were detected, in both rearing systems. Although some residues of organic pollutants were found in the analysed samples, they were always below the MRLs, so the results suggest that farmed sea bass are safe for human consumption.  相似文献   
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As part of an ongoing effort by the Ministry of Social Affairs and Employment of the Netherlands, a research project is being undertaken to construct a causal model for occupational risk. This model should provide quantitative insight into the causes and consequences of occupational accidents. One of the components of the model is a tool to systematically classify and analyse reports of past accidents. This tool ‘Storybuilder’ was described in earlier papers. In this paper, Storybuilder is used to analyse the causes of accidents reported in the database of the Dutch Labour Inspectorate involving people working in the construction industry. Conclusions are drawn on measures to reduce the accident probability. Some of these conclusions are contrary to common beliefs in the industry.  相似文献   
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为了更好地推进水平井钻井液的现场应用技术,论述了水平2井中出现的复杂事故、对煤层防塌及长段水平井钻井液的处理情况。试用了无机阳离子胶技术,较好地解决了井下漏失、井塌、携砂及润滑防卡等一系列问题,满足了钻井工程和保护油层的需要。  相似文献   
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The mucins of colonic murine mucus are highly O‐glycosilated sulfosialoglycoproteins. We have characterized the sialylation pattern of oligosaccharide chains of colonic murine mucins by conventional histochemical methods and by lectin histochemistry combined with chemical pretreatments and sialidase digestion. Oligosaccharide chains are strongly sulphated, with an increase of sulfation from the proximal toward the distal colon and a decrease of sialic acid expression and acetylation toward the distal colon. In the goblet cells of proximal colon, sialic acid bound α2,3 to Galβ1,3GalNAc subterminal dimers is diacetylated at C7,C8;C7,C9;C8,C9 or triacetylated at C7,8,9. In the distal colon, sialic acid‐linked α2,3 to Galβ1,3GalNAc subterminal dimers shows reduced O‐acetylation at C7 and/or C8, while acetyl substituents at C9 and at C4 are almost absent. Sialic acid is involved in different essential physiological functions; thus, alterations of its expression and acetylation in oligosaccharide chains of intestinal mucins are generally associated with diseases, such as ulcerative colitis and cancer. Mice may represent a suitable animal model to study alterations of oligosaccharidic chains in colonic mucins and lectin histochemistry combined with chemical pretreatments, and enzyme digestion may be a valuable tool for this study. Our present work may represent a landmark for further lectin histochemical studies to evaluate alterations of mouse colon mucins under different physiological, pathological, or experimental conditions, with possible translational value in humans. Microsc. Res. Tech., 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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