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《American journal of infection control》2022,50(6):618-623
BackgroundDuring COVID-19 pandemic, a shortage of surgical masks (Mask) and respirators (Resp) was experienced worldwide. We aimed to assess its pattern of use, adverse effects and user errors by Portuguese health care professionals (HCP).MethodsA cross-sectional study was conducted through snowball convenience sample, collected by email/ social media to health care organizations. Participants answered an online anonymous survey in March 2021.ResultsMean age of 3052 respondents was 42.1 years old, 83.6% were female and 77.8% provided direct health care to COVID-19 patients. Mean time of use per shift was 6-8 hours in 40.8% of the participants. 28.0% reported never changing it during their shift. Resp use (vs Mask) was more associated with discomfort (58.2% vs 26.8%), affecting task performance (41.5 vs 18.9%) and communication (55.0 vs 40.9%), dyspnea (36.0 vs 14.4%), skin rash (37.5 vs 19.4%) and headache (37.5 vs 19.4%). Frequent user errors included touching the front while in use (70.1% Mask vs 66.3% Resp) and omitting hand hygiene before (61.8% Mask vs 55.0% Resp) or after use (61.3% Mask vs 57.0% Resp). Average number of errors was higher for Mask (4.3), than for Resp (3.2) (all: P < .001).ConclusionsMost HCP admitted an extended use of Mask/ Resp. Resp were more prone to adverse effects and Mask more prone to errors. Strategies to reinforce good practices should be considered. 相似文献
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Julia R Dorin 《Asian journal of andrology》2015,17(5):716-719
β-defensin peptides are a large family of antimicrobial peptides. Although they kill microbes in vitro and interact with immune cells, the precise role of these genes in vivo remains uncertain. Despite their inducible presence at mucosal surfaces, their main site of expression is the epididymis. Recent evidence suggests that a major function of these peptides is in sperm maturation. In addition to previous work suggesting this, work at the MRC Human Genetics Unit, Edinburgh, has shown that homozygous deletion of a cluster of nine β-defensin genes in the mouse results in profound male sterility. The spermatozoa derived from the mutants had reduced motility and increased fragility. Epididymal spermatozoa isolated from the cauda region of the homozygous mutants demonstrated precocious capacitation and increased spontaneous acrosome reactions compared with those from wild-types. Despite this, these mutant spermatozoa had reduced ability to bind to the zona pellucida of oocytes. Ultrastructural examination revealed a disintegration of the microtubule structure of mutant-derived spermatozoa isolated from the epididymal cauda region, but not from the caput. Consistent with premature acrosome reaction and hyperactivation, spermatozoa from mutant animals had significantly increased intracellular calcium content. This work demonstrates that in vivo β-defensins are essential for successful sperm maturation, and that their disruption alters intracellular calcium levels, which most likely leads to premature activation and spontaneous acrosome reactions that result in hyperactivation and loss of microtubule structure of the axoneme. Determining which of the nine genes are responsible for the phenotype and the relevance to human sperm function is important for future work on male infertility. 相似文献
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《Radiography》2020,26(4):e195-e200
IntroductionAdverse events in radiology are quite rare, but they do occur. Radiation safety regulations and the law obligate organizations to report certain adverse events, harm and near misses, especially events related to patients' health and safety. The aim of this study was to describe and analyse incidents related to radiation safety issues reported in Finland.MethodsThe data were collected from incident reports documented by radiology personnel concerning notifications of abnormal events in medical imaging made to the Radiation and Nuclear Safety Authority between 2010 and 2017. During these eight years, 312 reports were submitted. Only events reported from radiology departments were included; nuclear medicine, radiotherapy and animal radiology cases were excluded. The final number of reports was 293 (94%).ResultsThe majority of the 293 approved reports were related to computed tomography (CT, 68.3%) and to X-ray examinations (27.6%). Altogether 82.9% of those irradiated were adults, most of whom were exposed to unnecessary radiation through CT (86.5%), 5.5% were children, and 4.4% pregnant women. The most common effective dose of unnecessary radiation was 1 mSv or less (89.7% of all examinations). The highest effective doses were reported in CT (from under 1 mSv–20 mSv and above). The reasons for the adverse events were incorrect identification (32%), incorrect procedure, site or side (30%); and human errors or errors of knowledge (20%).ConclusionAdverse events occurred especially in CT examinations. It is important to collect and analyse incident data, assess the harmful events, learn from them and aim to reduce adverse events.Implications for practiceThis study emphasizes the need for radiological personnel to obtain evidence-based information on adverse events and focus on training to improve patient safety. 相似文献
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陈振华 《中国卫生标准管理》2020,(8):76-79
目的探讨儿童流感应用帕拉米韦注射液治疗的临床疗效以及用药安全性。方法随机选定在2016年1月-2019年1月期间佛山市高明区人民医院儿科住院治疗并确诊流感A或B型患儿200例,通过随机数字法将其分为治疗组和对照组。治疗组100例用帕拉米韦注射液治疗,对照组100例用国产磷酸奥司他韦颗粒治疗,评价两组患儿治疗前后症状评分、治疗效果、治疗指标以及不良反应发生情况。结果两组患儿治疗前流感样症状评分无统计学意义(P>0.05),两组患儿治疗后较治疗前流感样症状评分均下降,差异有统计学意义(P<0.05);治疗组治疗后流感样症状评分略小于对照组,但是无统计学意义(P>0.05);治疗组治疗总有效率高于对照组,治疗组患儿发热症状缓解、全部症状缓解以及住院时间均小于对照组,存在统计学意义(P<0.05)。治疗组与对照组不良反应发生率较低,且无统计学意义(P>0.05)。结论帕拉米韦注射液可用于儿童流感治疗,不仅能够保证临床疗效,而且可加快症状缓解,同时存在较高用药安全性。 相似文献
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目的探讨极速实时荧光聚合酶链反应(polymerase chain reaction,PCR)、实时荧光PCR、酶联免疫吸附测定(enzyme-linked immunosorbent assay,ELISA)和胶体金免疫层析法(gold immunochromatography assay,GICA)4种方法检测新型布尼亚病毒的特异度和灵敏度,为发热伴血小板减少综合征的早期诊断提供依据。方法采集2017年6月1日至9月30日山东大学附属济南市传染病医院86例临床诊断为发热伴血小板减少综合征患者的血清样本,分别应用极速实时荧光PCR、实时荧光PCR、ELISA和GICA 4种方法进行检测。统计学分析采用χ^2检验。结果86份患者血清标本中,极速实时荧光PCR、实时荧光PCR、IgM-ELISA、IgG-ELISA、IgM-GICA、IgG-GICA的新型布尼亚病毒阳性分别为82份(95.34%)、79份(91.86%)、41份(47.67%)、8份(9.3%)、19份(22.09%)和3份(3.49%)。极速实时荧光PCR特异度为100%,灵敏度达到1×103拷贝/mL,3次重复扩增试验显示其Ct值变异系数均<2%。在发热伴血小板减少综合征进展的1期、2期、3期病程中,极速实时荧光PCR的阳性检出率为41份(97.62%)、34份(94.44%)、7份(87.50%),实时荧光PCR的阳性检出率为39份(92.86%)、33份(91.67%)、7份(87.50%),在1期和2期两个病程,极速实时荧光PCR阳性检出率略高;IgM-ELISA阳性检出率从1期(28.57%)到3期(87.50%)显著增高,2期、3期与1期相比,差异均有统计学意义(χ^2=8.347、7.561,均P<0.01);IgM-GICA的阳性检出率从1期(14.29%)到2期(33.33%)也有增高,差异有统计学意义(χ^2=3.962,P<0.05),但与其他方法相比,其检出率偏低。1期,实时荧光PCR阳性检出率显著高于ELISA(IgM和IgG)和GICA(IgM和IgG),差异均有统计学意义(χ^2=33.740、55.080、49.010、64.340,均P<0.01)。2期,实时荧光PCR的阳性检出率高于ELISA(IgM和IgG)和GICA(IgM和IgG),差异均有统计学意义(χ^2=7.700、46.720、23.700、50.630,均P<0.01)。3期,极速实时荧光PCR、实时荧光PCR和IgM-ELISA表现出同样高的阳性检出率,远高于IgG-ELISA和GICA(IgM和IgG)。实时荧光PCR阳性检出率和IgG-ELISA、IgM-GICA、IgG-GICA之间差异均有统计学意义(均χ^2=6.250,P<0.05)。结论极速实时荧光PCR在新型布尼亚病毒的早期检测中有更高的灵敏度和特异度,且重复性好、稳定度高,与传统实时荧光PCR相比大大缩短了扩增时间,对发热伴血小板减少综合征的早期快速诊断具有重要价值。 相似文献
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光化学作用对肿瘤细胞胞吞大分子的释放 总被引:1,自引:0,他引:1
目的观察不同光敏剂在肿瘤细胞内的分布,以及光化学作用对肿瘤细胞胞吞大分子的释放作用.方法使用激光共聚焦显微镜观察ALA、ALA-HE、HMME、TPPSa2在肿瘤细胞SW480、K562的胞内分布,使用FITC-右旋糖酐观察肿瘤细胞对荧光标记大分子的胞吞作用,通过光照激发光敏化细胞,动态观察光化学作用前后胞吞大分子FITC-右旋糖酐的胞内分布变化.结果ALA、ALA-HE、HMME、TPPSa24种光敏剂均表现为胞质分布,核内分布少.ALA、ALA-HE的胞内分布主要表现为胞质内的弥散性荧光.HMME则表现为胞质内颗粒状荧光与弥散荧光同时存在.TPPSa2为典型的胞质内颗粒状荧光分布.光敏剂在SW480、K562两种肿瘤细胞的胞内分布没有明显差异.光照激发不同光敏剂对肿瘤细胞胞吞FITC-左旋糖酐的胞内分布影响不同.由TPPSa2及HMME活化而产生的光化学作用表现出明显的荧光颗粒重分布,ALA、ALA-HE则对胞吞荧光无明显重分布作用.结论不同光敏剂因其不同的理化性质而表现为不同的胞内分布.光化学作用可对肿瘤细胞胞吞大分子产生胞吞释放作用,其作用机制可能与光化学作用对胞吞泡的破坏有关. 相似文献