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目的 对广州市越秀区学龄前儿童的流感经济负担进行评估,并针对流感疫苗开展卫生经济学评价,为制定免疫规划策略提供依据。方法 以广州市越秀区托幼机构2019年1—6月发生的9起流感样病例暴发疫情的患病儿童为研究对象,采用问卷调查的方式开展经济负担评估,并以其中1起暴发疫情为基础建立SEIAR动力学模型,模拟不同接种策略下的疫情趋势,评价其经济学效益。结果 患病儿童总经济负担人均1 293.56(95% UI:1 096.23~1 592.84)元,其中直接医疗费用人均422.56(95% UI:320.71~555.29)元,直接非医疗费用人均125.95(95% UI:82.41~188.80)元,间接经济损失人均797.03(95% UI:661.50~938.76)元。在流行季前接种1剂次三价流感疫苗,每投入226.19元,可减少1例流感病例,每投入1元,可获得5.72元效益;接种2剂次三价流感疫苗,每投入178.77元,可减少1例流感病例,每投入1元,可获得7.24元效益;接种四价流感疫苗,每投入315.83元,可减少1例流感病例,每投入1元,可获得4.10元效益。结论 广州市越秀区托幼机构流感样病例暴发疫情经济负担较高,如在流行季前接种2剂次三价流感疫苗,可以获得正效益和最好的效益成本比。  相似文献   
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目的探讨广东省放射诊疗工作人员个人剂量监测调查水平。方法采用方便抽样方法,以2016—2019年委托广东省职业病防治院个人剂量监测室进行个人剂量监测的广东省放射诊疗工作人员为调查对象,对其个人剂量进行监测与分析。结果2016—2019年分别监测诊断放射学、牙科放射学、核医学、放射治疗、介入放射学和其他应用工作人员53674、2563、5001、16687、22272和2087人次,超过调查水平(1.25 mSv)的分别有76、6、18、28、133和2人次,非真实剂量者分别占67.1%、100%、55.6%、82.1%、76.7%和100%。诊断放射学、牙科放射学、核医学、放射治疗、介入放射学和其他应用工作人员周期剂量当量第99百分位数(P99)分别为0.37、0.39、0.67、0.35、0.54和0.30 mSv,周期剂量当量均值分别为0.07、0.06、0.11、0.06、0.07和0.05 mSv。对各组人员周期剂量当量值两两比较,差异均有统计学意义(Z=-26.139~-2.681,P<0.001)。结论考虑超过目前调查水平数据的高不真实性和人工成本的因素,建议近似地将0.40 mSv/3个月作为目前诊断放射学、牙科放射学、放射治疗、其他应用放射工作人员的调查水平,将0.70 mSv/3个月作为目前核医学和介入放射学放射工作人员的调查水平。  相似文献   
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A hearing protection fit testing was conducted on workers (n = 189) in a textile factory in southern China. The 3M E-A-Rfit Dual-Ear Validation System was used to measure the personal attenuation rating (PAR) on an over-the-head style earmuff at the work site. In addition, PARs were obtained several times throughout the same work shift to capture different fits on 39 workers. Follow-up visits were conducted in approximate 6-month or 12-month intervals to repeat the fit testing. Both the immediate and residual effects of training on the field attenuation of hearing protection devices obtained by workers, and the effects of training toward improving the attenuation and protection of earmuffs after a period of daily use, were observed. A questionnaire survey was used to assess the awareness of hearing health and motivation toward the use of earmuffs in a high temperature environment. The results showed that there were wide variations in PARs among the workers tested. The one-on-one training together with fit testing improved PAR and helped to reduce the negative impact caused by use of protective hair covers. Since earmuffs are often used for long periods of time (>1 year), repeating fit tests could be helpful in order to verify the attenuation received throughout their useful life.  相似文献   
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目的 探索小鼠放射性肺损伤模型中大批量、快速、低成本实现全肺野精准照射的有效方法,普及这一重要放射生物学模型在多领域的应用。方法 采用8~10周龄C57BL6雌性小鼠,使用micro-CT三维重建图像进行肺部解剖学参数测量并确定放射野范围(n=12)。结合标准化胸腔暴露及固定、无创通气麻醉等手段建立"一体化"麻醉、固定、定位装置,借助常规医用直线加速器完成批量小鼠精准肺野照射。结果 小鼠CT图像三维重建后在冠状位与矢狀位图像上确定肺结构的解剖位置与尺寸平均值。并进一步根据小鼠呼吸频率及幅度确定受呼吸频率影响的肺野上界、中线和下界,并将测量值标记于专门设计的肺野照射装置用来指导实际操作。本装置大致可分为小鼠固定架和麻醉通气系统两部分构成。固定架用以安置每排10只小鼠用弹力栓妥善固定暴露胸腔。照射中通过麻醉面罩全程给予异氟烷混合气体,确保实验过程中小鼠处于深度麻醉以及均匀呼吸动度。结论 本研究设计的集麻醉、固定、定位为一体的"弹匣式"小鼠肺野照射装置,可显著增加胸部放射实验的准确性、简易性、安全性、稳定性和高效性。大幅减低实验成本和对高端辐照设备的依赖,具有一定的实际应用及推广价值。  相似文献   
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《Toxicology letters》2014,229(1):284-291
Dichlorodiphenyltrichloroethane (DDT), an organochlorine pollutant, is associated with several types of cancer. However, the relationship between DDT and colorectal cancer is uncertain. In this study, the impact of p,p′-DDT on colorectal cancer growth was evaluated using both in vitro and in vivo models. Our results indicated that the proliferation of human colorectal adenocarcinoma DLD1 cells was significantly promoted after exposed to low concentrations of p,p′-DDT ranging from 10−12 to 10−7 M for 96 h. Exposure to p,p′-DDT from 10−10 to 10−8 M led to upregulation of phospho-GSK3β (Ser9), β-catenin, c-Myc and cyclin D1 in DLD1 cells. RNA interference of β-catenin inhibited the proliferation of DLD1 cells stimulated by p,p′-DDT. Inhibiting of estrogen receptors (ERs) had no significant effect on the action of p,p′-DDT. Treatment with p,p′-DDT induced production of intracellular reactive oxygen species (ROS) and inhibited superoxide dismutase (SOD) activity in DLD1 cells. Treatment with N-acetyl-L-cysteine (NAC), a ROS inhibitor, suppressed the induction of Wnt/β-catenin signaling and DLD1 cell proliferation by p,p′-DDT. Moreover, in a mouse xenograft model, 5 nmol/kg p,p′-DDT resulted in increased tumor size, oxidative stress and Wnt/β-catenin signaling. These results indicated that low concentrations of p,p′-DDT promoted colorectal cancer growth through Wnt/β-catenin signaling, which was mediated by oxidative stress. The finding suggests an association between low concentrations of p,p′-DDT exposure and colorectal cancer progression.  相似文献   
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目的 通过对比对结果的分析,了解放射卫生技术服务机构在DR专项检测方面存在的问题,为提高检测能力提供依据。方法 采用整群抽样方法,以自愿参加本次比对的30家放射卫生技术服务机构为研究对象,采用基于四分位数稳健统计技术的z比分数对本次检测所提交的结果进行分析和评价。结果 在参加比对的30家机构所提交可分析的309项数据中,比对结果评价为满意的有267项,占比为86.4%;比对结果评价为可疑的有24项,占比为7.8%;比对结果离群的有18项,占比为5.8%。比对项目"STP"的结果最好,满意项占比为100%,比对项目"剂量测量"的离群结果占比最高,为20.0%,比对项目"极限空间分辨力"的可疑结果占比最高,为16.7%。结论 放射卫生技术服务机构技术水平有待提高,需加强日常质量控制管理,提升标准化操作意识,建设放射卫生检测数据平台,促进放射卫生检测行业健康发展。  相似文献   
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Zwitterionic sulfobetaine-based monolithic stationary phases have attracted increasing attention for their use in hydrophilic interaction chromatography. In this study, a novel hydrophilic polymeric monolith was fabricated through photo-initiated copolymerization of 3-(3-vinyl-1-imidazolio)-1-propanesulfonate (SBVI) with pentaerythritol triacrylate using methanol and tetrahydrofuran as the porogenic system. Notably, the duration for the preparation of this novel monolith was as little as 5 min, which was significantly shorter than that required for previously reported sulfobetaine-based monoliths prepared via conventional thermally initiated copolymerization. Moreover, these monoliths showed good morphology, permeability, porosity (62.4%), mechanical strength (over 15 MPa), column efficiency (51,230 plates/m), and reproducibility (relative standard deviations for all analytes were lower than 4.6%). Mechanistic studies indicated that strong hydrophilic and negative electrostatic interactions might be responsible for the retention of polar analytes on the zwitterionic SBVI-based monolith. In particular, the resulting monolith exhibited good anti-protein adhesion ability and low nonspecific protein adsorption. These excellent features seem to favor its application in bioanalysis. Therefore, the novel zwitterionic sulfobetaine-based monolith was successfully employed for the highly selective separation of small bioactive compounds and the efficient enrichment of N-glycopeptides from complex samples. In this study, we prepared a novel zwitterionic sulfobetaine-based monolith with good performance and developed a simpler and faster method for preparation of zwitterionic monoliths.  相似文献   
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