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81.
82.
Jehane Fadlallah Delphine Sterlin Claire Fieschi Christophe Parizot Karim Dorgham Hela El Kafsi Gaëlle Autaa Pascale Ghillani-Dalbin Catherine Juste Patricia Lepage Marion Malphettes Lionel Galicier David Boutboul Karine Clément Sébastien André Florian Marquet Christophe Tresallet Alexis Mathian Guy Gorochov 《The Journal of allergy and clinical immunology》2019,143(4):1575-1585.e4
83.
BACKGROUND: Exposure to fungi is often assessed by culturing floor dust or air samples. Our objective was to evaluate the relationships between dustborne and airborne fungi and to identify factors that modify these relationships. METHODS: From November 1994 to September 1996 sequential duplicate 45-l air samples were collected in bedrooms of 496 homes in the Boston area, using a Burkard culture plate sampler. After air sampling, bedroom floors were sampled with a vacuum cleaner that was modified to collect dust in a cellulose extraction thimble. Dust was sieved, and the fine dust was dilution-plated onto DG-18 media. RESULTS: Concentrations of total culturable fungi per gram of bedroom-floor dust were correlated weakly, but significantly, with those of indoor air (r = 0.13, P < 0.05). Concentrations of some individual taxa in the dust and indoor air were also weakly associated. Adjusting for the concentrations of fungi in outdoor air, dustborne fungal concentrations were positively associated with those in indoor air for the taxa Cladosporium and Penicillium, but not for total fungi. The indoor air fungal levels were often predicted by different covariates to those predicting fungal levels in dust. The type of housing (house or apartment) and the presence of carpeting were often predictive factors for dust fungi. In contrast, outdoor fungal levels were often predictive of the indoor air fungal levels. CONCLUSIONS: Because our data do not indicate a strong overall relationship between culturable fungi in dust and indoor air, the results from these two methods (dust and air sampling) likely represent different types of potential fungal exposures to residents. It may be essential to collect both air and dust samples, as well as information on housing characteristics, as indicators for fungal exposure. 相似文献
84.
Burkhard J Manfras William A Rudert Massimo Trucco Bernhard O Boehm 《Journal of immunological methods》1997,210(2):305
The characterization of the human T-cell receptor (TCR) repertoire in various physiological and pathological conditions has become an important tool in studies of the immune response. Therefore, a number of PCR based strategies for the semiquantitative analysis of the TCR repertoire have been described. Family specific amplification of TCR cDNA has been employed in a number of studies often with contradictory results. We have developed a strategy utilizing exogenous standards with homologous primer binding sites for the quantitative analysis of the α/β T-cell receptor repertoire. This system allows the detection of even minute differences in T-cell populations based on quantitative PCR (Q-PCR) and competitive PCR (C-PCR). Results presented here demonstrate that expansions of T-cell subsets as defined by the specificity of the variable gene segments can be readily monitored when exceeding 1% of the total repertoire. In addition, the proposed method reveals direct information of CDR3 size heterogeneity and can be used to estimate the T-cell repertoire complexity and monitor clonal expansions. We discuss variables such as cell number and experimental conditions influencing accuracy and reproducibility of the analyses. We have used this protocol based on non-radioactive techniques for characterization of the fine specificity of the T-cell repertoire in peripheral and organ-infiltrating T-lymphocytes. The analyses revealed information about polyclonal or clonal expansion of T-cells in vivo and in vitro following various stimuli such as superantigenic stimulation of T-cell subsets as well as antigen-driven shaping of the α/β T-cell repertoire in autoimmune and infectious diseases. 相似文献
85.
时间治疗学的计量研究 总被引:2,自引:0,他引:2
以《中国生物医学文献光盘数据库》(CBM)、《中文生物医学期刊文献数据库》(CMCC)和 OVID为数据源 ,全面检索时间治疗学的文献信息 ,利用文献管理软件 Pro Cite5辅助以手工方法对获取的信息进行管理和计量分析 ,以纳入文献的年代、期刊、著者、主题、国别和机构分布等科学和文献计量学指标全面揭示和评价时间治疗学的研究现状和发展趋势。研究结果显示 :时间治疗学的中文文献 91篇 ,分布于 73种期刊中 ,主题分布于中医学、心血管系统疾病、肿瘤、哮喘、消化性溃疡、糖尿病和时间治疗学总论等方面 ;同时纳入来自 35个国家和地区的有关外文文献 4 80篇 ,主要数据来源于 EMBASE和 MEDL INE,分布于 2 85种期刊中 ,收录时间治疗学文献 5篇以上的期刊有 14种 ,著者包括 12位 ,收录时间治疗学文献前 11名的机构分别为鲍尔勃罗斯医院、德州大学、康涅狄格州医学院、日本自治医学院、明尼苏达大学等。有关时间治疗学的研究 ,国内尚处于临床应用初期 ,国外已经形成核心著者、核心期刊和核心研究机构 ,主要分布在欧美等发达国家 ,已经在多个方面取得成绩。 相似文献
86.
Summary Possible toxic effects of chlorhexidine (CHX) on the sympathetic adrenergic ground plexus were studied in whole mounts of albino rat irides using Falck-Hillarp fluorescence histochemistry. CHX dissolved in an isotone, buffered sodium-acetate solution or in 70% alcohol was injected into the anterior chamber of eye. CHX caused a marked and dose-dependent degeneration of adrenergic nerves. Two days after the lowest dose, 0,25 g (5 l of a 0.05% CHX solution), approximately 30% of the nerves had disappeared. Almost complete degeneration was observed after the same time with higher doses (2.5 g, 5.0 g, and 7.5 g corresponding to 0.5, 1.0, and 1.5% CHX respectively). Two weeks after the lowest dose, the nerves had regenerated almost completely. With the highest dose used, only some 40% of the normal adrenergic nerve plexus had reformed after 51 days. Alcohol as a solvent did not have an additive effect on the neurotoxic action caused by CHX. The results demonstrate yet another aspect of chlorhexidine neurotoxicity, degeneration of peripheral adrenergic nerve terminals. This suggests that neurotoxic actions on thin unmyelinated fiber systems should be looked for also in the central nervous system (CNS).Supported by the Swedisch Council for Planning and Coordination of Research (Project: Chemical Hazards in the Environment), The Swedish Medical Research Council (14X-03185; 14P-5867; 04P-6889), Magnus Bergvalls Stiftelse, and Karolinska Institute Fonder 相似文献
87.
目的 了解四川省成人常住居民糖尿病患病情况及其影响因素,为有效预防糖尿病,降低发病风险提供科学的依据。方法 2018年采用多阶段分层整群随机抽样的方法,抽取四川省18岁及以上常住居民进行身体测量、问卷调查、实验室检测。采用SAS 9.4分析四川省成人糖尿病流行情况和患病影响因素。结果 2018年四川省成人糖尿病患病率12.94%,其中男性患病率为13.09%,女性患病率为12.79%,差异无统计学意义(χ2=3.964,P=0.460); 年龄增长(与18~44岁组相比,75岁及以上OR=6.070,95%CI:3.792~9.716)、职业(与农业生产人员相比,离退休人员OR=1.781,95%CI:1.277~2.484)、锻炼频率(与每周0次相比,每周1~3次OR=0.439,95%CI:0.281~0.686)、血脂异常(OR=2.069,95%CI:1.693~2.528)、中心性肥胖(OR=1.938,95%CI:1.619~2.320)、高血压(OR=2.031,95%CI:1.583~2.606)、糖尿病家族史(OR=2.825,95%CI:1.658~4.813)是糖尿病患病的影响因素。结论 四川省糖尿病患病率处于较高水平,每周锻炼1~3次是预防糖尿病的保护因素,年龄增加、离退休人员、血脂异常、中心性肥胖、高血压、糖尿病家族史是糖尿病患病的危险因素,应进一步开展针对性的预防干预措施。 相似文献
88.
目的 :对肝愈胶囊中苦参所含主要化学成分苦参碱含量进行测定。方法 :采用单波长薄层扫描法 ,λ =5 2 0nm ,SX =3。结果 :方法学考察结果表明 ,这种分析方法有较好的重现性和稳定性 ;测定方法的平均回收率为 98.2 9% ,RSD % =1.64%。结论 :方法简便、快速、准确、重现性好。 相似文献
89.
福建省城乡人群恒牙龋病流行病学抽样调查报告 总被引:20,自引:7,他引:13
目的:了解福建省居民口腔健康状况及流行趋势,为今后进行口腔健康教育、开展口腔保健项目提供依据。方法:采用多阶段、分层、整群随机抽样的方法对福州市、泉州市、南平市的5,12,15,18,35-44及65-74岁年龄组的城乡人群12792人(男女各半)进行口腔检查。结果:随着年龄的增大,龋均、患龋率、充填率呈上升趋势(P<0.01)。35-44岁、65-74岁年龄组龋均、患龋率城市高于农村(P<0.01),其他年龄组城乡之间差别无显著性(P>0.05)。各年龄组充填率城市均高于农村(P<0.01)。福建省城乡居民的恒牙患龋率、龋均高于全国平均水平。结论:应从小进行口腔健康教育,增强口腔健康意识,加大实施口腔预防保健措施的力度。 相似文献
90.
Molly E. Baumann Danielle M. DeBruler Britani N. Blackstone Rebecca A. Coffey Steven T. Boyce Dorothy M. Supp J. Kevin Bailey Heather M. Powell 《Burns : journal of the International Society for Burn Injuries》2021,47(2):466-478
IntroductionDetermining the efficacy of anti-scar technologies can be difficult as qualitative, subjective assessments are often utilized instead of systematic, objective measures. Perceptions regarding the reliability of instruments for quantitative measurements along with their high cost and increased data collection time may discourage their use, leading to use of scar scales which are relatively quick and low-cost. To directly evaluate the reliability of instruments for quantitative measurements of scar properties, instruments and two qualitative scales were compared by assessing a variety of cutaneous scars.MethodsScar height and surface texture were evaluated using a 3D scanner and a mold/cast technique. Scar color was evaluated by using a spectroscopy-based tool, the Mexameter®, and digital photography with image analysis. Scar biomechanics were evaluated using the BTC-2000?, Dermal Torque Meter (DTM®), and ballistometer®. The Vancouver Scar Scale (VSS) and Patient and Observer Scar Assessment Scale (POSAS) were used to qualitatively evaluate the same scar properties. Intraclass correlation coefficients (ICC) were used to determine inter- and intra-user reliability (poor, moderate, good, excellent) with all instruments and the kappa reliability statistic was used to asses inter-user reliability (poor, fair, moderate, good, very good) for VSS and POSAS. Time for measurement collection and after collection analysis was also recorded.ResultsThe Mexameter® was the most reliable method for evaluating erythema and pigmentation compared to digital photography and image processing, POSAS and VSS. Digital photography and analysis was more reliable than POSAS and VSS. Assessment of scar height was significantly more reliable when using a 3D scanner versus VSS and POSAS. The 3D scanner and mold-cast techniques also offered an additional benefit of providing an absolute value of scar height relative to the surrounding tissue. Intra-user reliability for all mechanical tests was moderate to good. Inter-user reliability was greater when using the BTC-2000? and ballistometer® versus the DTM®. All quantitative measurements took less than 90 s for collection, with the exception of the mold/cast technique.ConclusionNon-invasive instruments allow scar properties to be quantitatively assessed with high sensitivity and as a function of time and/or treatment without the need for biopsy collection. Overall, the reliability of scar assessments was significantly improved when quantitative instruments were utilized versus scar scales. Quantitative assessment of color and biomechanics were swift, requiring less than 90 s per measurement while assessments of texture and height required additional analysis time after collection. With proper training of clinical staff and well-defined protocols for measurement collection, reliable, quantitative assessments of scar properties can be collected with little disruption to the clinical workflow. 相似文献