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Dry powder inhalers (DPIs) are gaining popularity for the delivery of drugs. A cost effective and efficient delivery device is necessary. Developing new DPIs by modifying an existing device may be the simplest way to improve the performance of the devices. The aim of this research was to produce a new DPIs using computational fluid dynamics (CFD). The new DPIs took advantages of the Cyclohaler® and the Rotahaler®. We chose a combination of the capsule chamber of the Cyclohaler® and the mouthpiece and grid of the Rotahaler®. Computer-aided design models of the devices were created and evaluated using CFD. Prototype models were created and tested with the DPI dispersion experiments. The proposed model 3 device had a high turbulence with a good degree of deagglomeration in the CFD and the experiment data. The %fine particle fraction (FPF) was around 50% at 60?L/min. The mass median aerodynamic diameter was around 2.8–4?μm. The FPF were strongly correlated to the CFD-predicted turbulence and the mechanical impaction parameters. The drug retention in the capsule was only 5–7%. In summary, a simple modification of the Cyclohaler® and Rotahaler® could produce a better performing inhaler using the CFD-assisted design. 相似文献
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Is it possible to make a diagnosis of raw,heated, and baked egg allergy in children using cutoffs? A systematic review 下载免费PDF全文
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Jennifer J. Schoch Reesa L. Monir Kerrie G. Satcher Jessica Harris Eric Triplett Josef Neu 《Pediatric dermatology》2019,36(5):574-580
Recent focus on the neonatal intestinal microbiome has advanced our knowledge of the complex interplay between the intestinal barrier, the developing immune system, and commensal and pathogenic organisms. Despite the parallel role of the infant skin in serving as both a barrier and an interface for priming the immune system, large gaps exist in our understanding of the infantile cutaneous microbiome. The skin microbiome changes and matures throughout infancy, becoming more diverse and developing the site specificity known to exist in adults. Delivery method initially determines the composition of the cutaneous microbiome, though this impact appears transient. Cutaneous microbes play a critical role in immune system development, particularly during the neonatal period, and microbes and immune cells have closely intertwined, reciprocal effects. The unique structure of newborn skin influences cutaneous microbial colonization and the development of dermatologic pathology. The development of the infantile skin barrier and cutaneous microbiome contributes to future skin pathology. Atopic dermatitis flares and seborrheic dermatitis have been linked to dysbiosis, while erythema toxicum neonatorum is an immune response to the establishment of normal bacterial skin flora. Physicians who care for infants should be aware of the impact of the infantile skin microbiome and its role in the development of pathology. A better understanding of the origin and evolution of the skin microbiome will lead to more effective prevention and treatment of pediatric skin disease. 相似文献
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Studying skin barrier function is central to our understanding of many skin disorders. The past decade has seen a surge of skin barrier related investigative work. Genetic, biochemical and cell biology experiments have added much evidence to the importance of the barrier in disease pathogenesis of a variety of disorders including ichthyosis, atopic dermatitis and psoriasis. However, functional assays prove ever more important to demonstrate relevance of any of these findings. A paper published by Monash and Blank 60 years ago describes a stress test of the skin barrier, measuring skin barrier recovery, a functional test of tremendous implications. This seminal paper has not been cited for almost 15 years, time to acknowledge its critical importance and to review the relevance of this method today. 相似文献
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目的观察消风散合凉血五根汤联合西药治疗成人过敏性紫癜性肾炎(HSPN)的临床疗效及对患者血表皮生长因子(EGF)、血小板活化因子乙酰水解酶(PAF-AH)的影响。方法将90例成人HSPN患者按照随机数字表法分为2组。对照组45例予常规西医治疗;治疗组45例在对照组基础上加服消风散合凉血五根汤治疗。2组均治疗8周。比较2组治疗前后中医证候评分、血肌酐(Cr)、尿素氮(BUN)、24 h尿蛋白定量、尿红细胞计数(U-RBC)、尿微量白蛋白尿肌酐比值(UACR)、估算肾小球滤过率(e GFR)、血EGF、PAF-AH水平,并统计2组临床疗效及不良反应情况。结果治疗组总有效率88.89%,对照组总有效率68.89%,治疗组疗效优于对照组(P<0.05)。治疗后2组各项中医证候评分及总分均降低(P<0.05),治疗组治疗后各项中医证候评分及总分均低于对照组(P<0.05)。治疗后2组Cr、BUN、24 h尿蛋白定量、U-RBC、UACR均降低(P<0.05),e GFR升高(P<0.05);治疗组治疗后Cr、BUN、24 h尿蛋白定量、U-RBC、UACR均低于对照组(P<0.05),e GFR高于对照组(P<0.05)。治疗后2组血EGF、PAF-AH水平均降低(P<0.05),治疗组治疗后血EGF、PAF-AH水平均低于对照组(P<0.05)。治疗组不良反应率(11.11%)低于对照组(26.67%,P<0.05)。结论成人HSPN在西医治疗基础上,加用消风散合凉血五根汤可提高临床疗效,不仅可改善临床症状,还能改善肾功能,降低糖皮质激素不良反应,其机制之一可能与其下调血EGF、PAF-AH水平有关。 相似文献
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目的: 应用文献计量学方法,分析国内外医用粘胶相关性皮肤损伤(Medical adhesive-related skin injuries,MARSI)文献的研究主题和热点。方法: 检索Cochrane Library、PubMed、EMbase、Web of science、sinoMed、CNKI、Wanfang、VIP等数据库MARSI相关文献,检索时限为建库至2019年5月。采用SPSS 22.0 软件进行文献计量分析,利用gCLUTO统计对国内外高频主题词进行聚类分析。结果: 共纳入论文103篇,其中外文文献占总文献量的27.18%,中文文献占总文献量的72.82%。聚类分析将国内外高频主题词聚为4大类,依次为皮肤损伤及损伤类型、相关危险因素、风险评估及风险管理、护理干预措施。结论: MARSI仍是国内外研究的热点,其发病机制研究仍处于探索阶段,目前尚缺乏有效的预防策略,研究领域较局限。在今后的研究中,应加强MARSI预防的研究、注重多学科合作。 相似文献