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991.
Aims/hypothesis Recent studies have shown that the inflammatory process is involved in the pathogenesis of diabetic nephropathy. Fourteen-membered ring macrolides, including erythromycin, have anti-inflammatory, as well as antibacterial effects. The aim of this study was to investigate the renoprotective effects of erythromycin in streptozotocin (STZ)-induced diabetic rats.Methods STZ-induced diabetic rats were treated orally with erythromycin (5 mg/kg body weight) or vehicle every day for 8 weeks. To evaluate the effect of erythromycin treatment, we measured urinary albumin excretion, and examined the following in the kidney: histological changes, the expression of intercellular adhesion molecule-1 (ICAM-1), macrophage infiltration, and nuclear factor-kappa B (NF-content/k5412j18x3104j40/xxlarge954.gif" alt="kappa" align="BASELINE" BORDER="0">B) activity.Results Erythromycin significantly reduced urinary albumin excretion without affecting blood glucose levels and blood pressure. Erythromycin also attenuated glomerular hypertrophy, mesangial expansion, macrophage infiltration and ICAM-1 expression in renal tissues. The expression of the gene encoding TGFB1 (also known as TGF-content/k5412j18x3104j40/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">1), type IV collagen protein production and NF-content/k5412j18x3104j40/xxlarge954.gif" alt="kappa" align="BASELINE" BORDER="0">B activity in renal tissues were increased in diabetic rats and reduced by erythromycin treatment.Conclusions/interpretation Erythromycin prevented renal injuries without changes of blood glucose levels and blood pressure in experimental diabetic rats. These results suggest that the renoprotective effects of erythromycin are based on its anti-inflammatory effect via suppression of NF-content/k5412j18x3104j40/xxlarge954.gif" alt="kappa" align="BASELINE" BORDER="0">B activation. Modulation of microinflammation with erythromycin may provide a new approach for diabetic nephropathy.  相似文献   
992.
We tested the hypotheses that the protective effect of intragastric nicotine against ethanol-induced gastric mucosal injury is dependent on propranolol- orN-ethylmaleimide-sensitive mechanisms. Propranolol was administered in doses (2 and 20 mg/kg) that provided dose-related blockade of content/j06616jh3q931364/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-adrenoceptors (significant decreases in heart rate).N-Ethylmaleimide was administered in doses that previously had been shown to increase gastric vascular permeability (10 mg/kg) or inhibit gastric mucosal sulfhydryl compounds (50 mg/kg). At 0.5 hr after these or control subcutaneous pretreatments, the rats received intragastric nicotine (4 mg/kg) or vehicle. One hour later 40% ethanol was given intragastrically. The gastric corpus mucosal lesions were recorded by polaroid photographs after another hour, and their areas measured unbiasedly by computerized image analysis. The results showed thatN-ethylmaleimide, but not propranolol, aggravated ethanol-induced gastric mucosal injury. The protective effect of intragastric nicotine was not modified by either pretreatment. We conclude that the mechanism mediating intragastric nicotine protection against 40% ethanol-induced gastric mucosal injury is independent of propranolol- orN-ethylmaleimide-sensitive mechanisms.Supported by Veterans Administration Medical Research Funds, and in part by research grants (0162-01, 02 and 0291-01) from the Smokeless Tobacco Research Council, Inc., and by funds (1RT 80) provided by the Cigarette and Tobacco Surtax Fund of the State of California through the Tobacco-Related Disease Research Program of the University of California to FWL. Dr. Endoh is a recipient of the University of California Tobacco-Related Disease Research Program Research Fellowship Award (FT 37).  相似文献   
993.
994.
995.
目的:调研四川市售白芍饮片质量。方法:随机采购四川市售白芍饮片16批,参照现行2010版药典的规定,测定饮片水分、总灰分、水溶性浸出物,并采用HPLC法测定芍药苷含量。结果:16批次白芍饮片中仅3批次芍药苷的量符合药典规定,9批次水分符合药典规定。结论:白芍饮片存在的质量问题主要是芍药苷含量和水分含量不合格。针对导致白芍药材或饮片质量问题的多种原因,药品监督管理部门应加强监督管理,规范饮片市场。  相似文献   
996.
997.
When an additive is used to replace a certain amount of cement, a concrete pore structure becomes dense. Thus, it results in inhibiting the penetration of chlorine ions and suppressing corrosion of reinforcing bars. However, the pH level of the concrete decreases, and it deteriorates the performance of the passive film formed on the surface of the rebars embedded in the concrete. Therefore, in this study, the service lives of reinforced concrete containing different types of concrete binders were predicted and compared. The chloride ion diffusion coefficients of concretes with various binders were measured, and the critical chloride content of the rebar was assessed by the real-time monitoring on the corrosion initiation time of the rebar embedded in concrete. Moreover, Fick’s 2nd law was applied to predict when the chloride content at the 40 mm depth of cover reached the critical chloride content based on the chloride ion diffusion coefficient. It was observed that the service life of S6 (OPC 40% + GGBFS 60%) was the highest, followed by TBC (OPC 40% + GGBFS 40% + FA 20%), S3 (OPC 70% + GGBFS 30%), and OPC (OPC 100%).  相似文献   
998.
背景 在加速推进家庭医生责任制服务进程中,为家庭医生配置类似助手的角色,可有效提升家庭医生的服务效率,该助手角色通常被称为家庭医生助理。上海、北京等社区卫生服务中心已经构建了以家庭医生为核心和责任主体的、护士作为主要助理人员的服务模式。但对于家庭医生团队的核心人员结构、家庭医生助理的人员特征、工作范围和薪酬体制等还缺少统一的标准。目的 了解国内外家庭医生助理的服务模式运行现况,为我国家庭医生助理的服务模式建设提供借鉴。方法 于2019年11月5-20日,选择PubMed、ScienceDirect、中国知网(CNKI)和万方数据知识服务平台为文献搜索引擎,在数据库中检索与家庭医生助理模式(包括家庭医生助理的人员配置及人员特征、主要职责及服务内容、绩效考核方式及分配方式等)相关的文献,检索时间范围为2009-2019年,检索词(主题词或关键词)为“family physician assistant”OR“general practitioner assistant”OR“全科医生助理”OR“家庭医生助理”OR“家庭医生”AND“助理”OR“全科医生”AND“助理”。通过评阅文献内容,总结国内外家庭医生助理模式开展现状。结果 阅读全文后最终获得符合要求的文献47篇,其中英文文献31篇,中文文献16篇。家庭医生助理主要由专职医生助理、护士、公共卫生医生、乡村医生、“3+2”助理全科医生担任;人员特征方面,国外的医生助理通常为接受过“医生助理”项目培训并取得相应资格或学历的专业人员;中国承担家庭医生助理的专职医生助理主要由非医学专业人员经过岗位培训后担任,担任家庭医生助理的护士、公共卫生医生和乡村医生都是由社区卫生服务中心在岗的卫生专业人员兼任。家庭医生助理的职责范围在不同国家有不同的规定,主要包括患者治疗方案的实施、健康管理、健康宣教、患者分诊、健康初步评估、慢性病随访等。在绩效考核方式方面,国外家庭医生助理一般由机构根据统一的考核指标体系进行考核,或由家庭医生直接对助理进行考核;中国家庭医生助理的绩效考核方式包括二级考核,机构质控部门统一考核,涉及全中心的工作内容由机构统一考核、与家庭医生工作相关内容由家庭医生考核。结论 国内外家庭医生助理在人员特征、主要职责和绩效考核分配方式上存在较大差异,建议构建以“全科医生+护士/乡村医生”或“全科医生+专职助理”为核心人员的家庭医生服务团队,分类设立家庭医生助理的岗位职责和服务内容,建立以“医疗技术的复杂程度”“服务质量”“工作数量”作为主要绩效考核指标的薪酬分配制度。  相似文献   
999.
目的:研究白芍总苷对小鼠皮肤机械屏障受损的修复作用及可能机制。方法:雌性ICR小鼠随机分为正常组、模型组、白芍总苷低剂量(0.2 mg/g)组、白芍总苷高剂量(0.4 mg/g)组和糠酸莫米松(1 mg/g)组,每组12只。除正常组外,其余各组采用胶带法诱导小鼠皮肤机械屏障损伤模型,连续5 d。第6天起,各组给予相应药物外用干预,0.3 g/只,正常组和模型组给予等量水凝胶基质,连续14 d。末次给药后,检测受损皮肤的含水量、油脂含量及pH值。分离受损皮肤组织,HE染色后光镜下观察皮肤组织形态学变化,试剂盒检测皮肤组织白介素-6(IL-6)和神经酰胺的含量。结果:①HE染色观察显示,模型组小鼠皮肤炎症细胞浸润,角质层增厚,腺上皮细胞增多;白芍总苷干预后上述病变情况明显改善,高剂量组作用更为显著。②与正常组相比,模型组小鼠受损皮肤的含水量、油脂含量及pH值明显降低(P0.01);与模型组相比,糠酸莫米松组及白芍总苷高、低剂量组小鼠的皮肤含水量均显著升高(P0.05,P0.01),糠酸莫米松组及白芍总苷高剂量组小鼠皮肤的油脂含量亦显著升高(P0.01)。③与正常组相比,模型组小鼠皮肤组织IL-6含量显著升高(P0.05),神经酰胺含量显著降低(P0.01);与模型组相比,白芍总苷高剂量组和糠酸莫米松组小鼠皮肤组织的IL-6含量明显降低(P0.05,P0.01),神经酰胺含量明显升高(P0.01)。结论:白芍总苷可修复皮肤机械屏障受损,其机制可能与降低角质层中炎症介质IL-6的含量、增加角质层中神经酰胺的含量有关。  相似文献   
1000.
Tens of millions of individuals around the world use decentralized content distribution systems, a fact of growing social, economic, and technological importance. These sharing systems are poorly understood because, unlike in other technosocial systems, it is difficult to gather large-scale data about user behavior. Here, we investigate user activity patterns and the socioeconomic factors that could explain the behavior. Our analysis reveals that (i) the ecosystem is heterogeneous at several levels: content types are heterogeneous, users specialize in a few content types, and countries are heterogeneous in user profiles; and (ii) there is a strong correlation between socioeconomic indicators of a country and users behavior. Our findings open a research area on the dynamics of decentralized sharing ecosystems and the socioeconomic factors affecting them, and may have implications for the design of algorithms and for policymaking.Every month, ∼150 million users worldwide share files over the Internet using BitTorrent (1), the most widely used decentralized peer-to-peer (P2P) communication protocol. Eleven years after its inception, file sharing through BitTorrent is one of the top three major contributors to the overall Internet traffic, accounting for 9–27% of the total traffic, depending on the continent (2, 3).The expansion in scale and breadth of decentralized file-sharing has highlighted the conflicts between the interests of creators (musicians and writers, e.g.) and those of P2P users. Creators and creative industries argue that they are being deprived of fair compensation for their work (4), which is being widely distributed for free in violation of copyright laws. Users, however, argue that P2P can be (and is) used for sharing nonproprietary contents, and warn that widespread monitoring of online activity by corporations and law enforcement violates P2P users’ right to privacy. Proof of the complexity of the situation includes the rejection of the Anti-Counterfeiting Trade Agreement by the European Parliament and the controversy with the Stop Online Piracy Act in the United States.Despite the growing social, economic, and technological importance of BitTorrent (4), there is currently little understanding of how users behave in this complex technosocial (5, 6) ecosystem. Due to the decentralized structure of P2P ecosystems, it is very difficult to gather large-scale data about interactions and behavioral patterns of the users without their explicit consent; this is in contrast to other forms of online exchange where all of the information is stored in a central system, be it publicly accessible as in Wikipedia (7), partially accessible through a public interface as in Twitter (8, 9) or Google [through its search logs (10) or its public services (11, 12)], or restricted as in Facebook (13, 14) or in email communications within organizations (1518).Because of the difficulty to collect complete user-level data of large and representative samples of users (3), studies of user behavior in P2P networks have so far been based on (i) small datasets; (ii) aggregate data collected from “trackers” or from individual Internet service providers (ISPs); and (iii) incomplete user data collected using a single crawler client connected to the network (1923).Here, we investigate the complete activity patterns of a large and representative pool of BitTorrent users. Our analysis reveals that P2P sharing is highly heterogeneous, that users are specialized, giving rise to well-defined user profiles, and that the abundance of certain user profiles in a country is highly correlated with socioeconomic factors. Our findings open a research area on the dynamics of decentralized sharing ecosystems, and may have implications for the understanding and design of algorithms and for policymaking.  相似文献   
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