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1.
IntroductionDetailed data on clinical characteristics in children with the omicron strain of SARS-COV-2 are limited.MethodsWe conducted a retrospective observational study of children with COVID-19 at the National Center for Child Health and Development to evaluate the clinical manifestations during and before the emergence of the omicron variant. Only symptomatic patients without underlying diseases were included. Participants were divided into two temporal groups: the “omicron era” (1/2022–2/2022) and the “pre-omicron era,” where the delta variant predominated (7/2021–11/2021). The patients were subclassified into an older vaccine-eligible group (aged 12–17 years), a younger vaccine-eligible group (aged 5–11 years), and a vaccine-ineligible group (aged 0–4 years).ResultsWe compared 113 patients in the omicron era with 106 in the pre-omicron era. Most patients in both eras had non-severe disease, and no patients required mechanical ventilation or died. Among patients aged 0–4 years, sore throat and hoarseness were more common during the omicron era than the pre-omicron era (11.1% vs. 0.0% and 11.1% vs. 1.5%, respectively). Croup syndrome was diagnosed in all patients with hoarseness. Among patients aged 5–11 years, vomiting was more frequent during the omicron era (47.2%) than during the pre-omicron era (21.7%). Cough and rhinorrhea were less common during the omicron era in patients aged 0–4 and 5–11 years, respectively, than during the pre-omicron era.ConclusionsIn children with COVID-19, clinical manifestations differed between the omicron and pre-omicron eras. In the Omicron era, croup syndrome was more frequent in vaccine-ineligible children.  相似文献   
2.
BackgroundVaccines are critical cost-effective tools to control the coronavirus disease 2019 (COVID-19) pandemic. However, the emergence of variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may threaten the global impact of mass vaccination campaigns.AimsThe objective of this study was to provide an up-to-date comparative analysis of the characteristics, adverse events, efficacy, effectiveness and impact of the variants of concern for 19 COVID-19 vaccines.SourcesReferences for this review were identified through searches of PubMed, Google Scholar, BioRxiv, MedRxiv, regulatory drug agencies and pharmaceutical companies' websites up to 22nd September 2021.ContentOverall, all COVID-19 vaccines had a high efficacy against the original strain and the variants of concern, and were well tolerated. BNT162b2, mRNA-1273 and Sputnik V after two doses had the highest efficacy (>90%) in preventing symptomatic cases in phase III trials. mRNA vaccines, AZD1222, and CoronaVac were effective in preventing symptomatic COVID-19 and severe infections against Alpha, Beta, Gamma or Delta variants. Regarding observational real-life data, full immunization with mRNA vaccines and AZD1222 seems to effectively prevent SARS-CoV-2 infection against the original strain and Alpha and Beta variants but with reduced effectiveness against the Delta strain. A decline in infection protection was observed at 6 months for BNT162b2 and AZD1222. Serious adverse event rates were rare for mRNA vaccines—anaphylaxis 2.5–4.7 cases per million doses, myocarditis 3.5 cases per million doses—and were similarly rare for all other vaccines. Prices for the different vaccines varied from $2.15 to $29.75 per dose.ImplicationsAll vaccines appear to be safe and effective tools to prevent severe COVID-19, hospitalization, and death against all variants of concern, but the quality of evidence greatly varies depending on the vaccines considered. Questions remain regarding a booster dose and waning immunity, the duration of immunity, and heterologous vaccination. The benefits of COVID-19 vaccination outweigh the risks, despite rare serious adverse effects.  相似文献   
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4.
Even at low to moderate-speeds, rear-end motor vehicle crashes have been strongly associated with occupant cervicocranial biomechanics that lead to head and neck injury. In this paper, we present the development of an analytic mechanics model of occupant head and neck motion as associated with modeled target vehicle Delta V during rear-end vehicular crashes. The inclusion of stochastic mechanical input variables further developed the model beyond the deterministic framework by reflecting aspects of the random nature of real-world crashes and the resulting injuries. This approach led to the characterization of 1000 crash simulations, quantifying Delta V and the resulting probabilistic occupant biomechanics. The model was validated through the direct comparison with 86 published human subject crash tests. Overall, the model slightly underestimated by −2.6% the magnitude of peak head accelerations identified in the literature. The utility of the model allows a forensic biomechanical investigator to customize some of the fundamental input crash parameters and appropriately explore the resulting vehicular mechanics and their direct influence on injury biomechanics.  相似文献   
5.
长三角一体化上升并发展为国家战略后,国内鲜有探讨长三角地区生物医药产业一体化协同发展的研究,长三角作为我国生物医药产业的重要地区,已初步形成产业集群的发展模式。本研究基于专利及基金项目合作的产学研模式,利用社会网络分析方法(SNA)对长三角地区生物医药产业中专利和国家自然科学基金重大项目合作进行分析研究。研究表明,长三角地区生物医药领域的产学研合作还处于发展阶段,一体化程度也有待提高;高校及科研院所更倾向于与企业合作开展发明专利,与高校合作开展基金项目研究。长三角地区三省一市间的生物医药产业发展也存在一定差距,建议长三角地区采取产学研深度融合模式,相关龙头科研机构建立开放式创新平台,医药类高校借助学科优势培养创新型人才,采取“揭榜挂帅”等方式进行关键核心技术攻关。  相似文献   
6.
经Delta通道椎间孔镜治疗神经根型颈椎病   总被引:1,自引:1,他引:0  
邱峰  张贤  李小军  尹恒  刘一奇 《中国骨伤》2020,33(5):397-401
目的:探讨经Delta通道椎间孔镜治疗神经根型颈椎病的早期临床疗效及安全性。方法:对2017年9月至2018年7月收治的10例神经根型颈椎病患者行经Delta通道后路椎间孔镜下椎间盘摘除术,其中男6例,女4例;年龄30~62(41.5±4.3)岁;均为单侧根性症状,其中C_(4,5) 2例,C_(5,6) 5例,C_(6,7) 3例。所有患者CT及MRI检查提示无后纵韧带骨化及黄韧带钙化等影像学表现,颈椎动力位X线片无颈椎不稳,经系统非手术治疗6周以上,疗效欠佳。观察患者术前及末次随访时颈肩痛VAS评分、JOA评分、NDI评分、颈椎生理曲度、颈椎病变节段椎间高度和稳定性的改变。结果:所有手术顺利完成,无脊髓、神经根或大血管损伤情况的发生。手术时间70~120 min,平均90 min;术中出血量30~90 ml,平均40 ml。10例患者均获得随访,时间6~14个月,平均9个月。所有患者术后神经根性疼痛缓解满意,神经功能有所改善。VAS评分由术前的7.15±2.01降至末次随访时的1.59±0.83;JOA评分由术前的12.57±1.24升至末次随访时的16.42±0.58;NDI评分由术前的41.82±4.71提高到末次随访时的9.59±3.52;末次随访与术前比较差异均有统计学意义(P0.05)。颈椎生理曲度D值由术前的(8.21±0.84) mm升至末次随访时的(10.89±0.96) mm (P0.05)。病变节段椎间高度术前、末次随访时分别为(5.62±0.59)、(5.60±0.57) mm,差异无统计学意义(P0.05)。末次随访时颈椎动力位X线片未见颈椎失稳。结论:经Delta通道后路椎间孔镜下椎间盘摘除术治疗神经根型颈椎病能取得较为满意的疗效,且不影响颈椎的稳定性,安全性可靠,值得临床应用。  相似文献   
7.
《Clinical neurophysiology》2021,132(2):545-553
ObjectiveTo determine the best of commonly used methods for computing the rate of decline in non-rapid eye movement (NREM) sleep EEG delta power overnight (Delta Decline) in terms of vulnerability to missing data and to evaluate whether this rate is slower in insomnia patients than healthy controls (HC).MethodsFifty-one insomnia patients and 53 HC underwent 6 nights of polysomnography. Four methods for estimating Delta Decline were compared (exponential and linear best-fit functions using NREM (1) episode mean, (2) peak, and (3) total delta power and (4) delta power for all available NREM epochs). The best method was applied to compare groups on linear and exponential rates of Delta Decline.ResultsBest-fit models using all available NREM epochs were significantly less vulnerable to deviation due to missing data than other methods. Insomnia patients displayed significantly slower linear and exponential Delta Decline than HC.ConclusionsComputing Delta Decline using all available NREM epochs was the best of the methods studied for minimizing the effects of missing data. Insomnia patients display slower Delta Decline, which is not explained by differences in total sleep time or wake after sleep onset.SignificanceThis study supports using all available NREM epochs in Delta Decline computation and suggests a slower rate in insomnia.  相似文献   
8.
Haemostatic treatment in women experiencing postpartum haemorrhage is increasingly based on point-of-care devices such as ROTEM® thromboelastometry. Recently, a fully automated successor of the ROTEM® Delta device, the ROTEM® Sigma was introduced. To determine whether these devices provide similar results, we compared ROTEM® parameters using the ROTEM® Delta and Sigma devices in women experiencing postpartum haemorrhage. Prospective observational cohort study of 23 women experiencing postpartum haemorrhage. ROTEM® INTEM, EXTEM, FIBTEM and APTEM measurements handled by the ROTEM® Delta and Sigma devices were compared. ROTEM® FIBTEM values were also related to Clauss fibrinogen values. A correlation of Spearman’s r (rs) varying between 0.76 and 0.95 was displayed between clot firmness measured in millimeters at 5 (A5), 10 (A10) and 20 (A20) minutes after start of clot formation measured by EXTEM, INTEM and APTEM assays executed on both devices; A5, A10 and A20 of FIBTEM correlated less well (rS between 0.71 and 0.74), especially after five and ten minutes. Correlation between both devices regarding clotting time (CT) was poor. The observed correlation between levels of Clauss fibrinogen and FIBTEM A5 was rs = 0.70, (95% confidence interval (CI): 0.38 to 0.87) for Delta and rs = 0.85, (CI 0.65 to 0.94) for Sigma. A5, A10 and A20 measured in EXTEM, INTEM and APTEM obtained from ROTEM® Delta and Sigma devices were similar. EXTEM, FIBTEM and APTEM CT values from both devices showed no correlation. Substantial variation was found between FIBTEM assays of the devices. Consequently, results of FIBTEM assays should always be interpreted in the context of device-specific reference values. Correlation with Clauss fibrinogen was better in the ROTEM® Sigma device.  相似文献   
9.
Delta variant of concern (VOC) is the current predominant severe acute respiratory coronavirus type 2 strain causing coronavirus disease 2019 (COVID-19); however, information regarding the impact of the Delta VOC on clinical features and outcomes in pediatric patients with COVID-19 is limited. We conducted a retrospective observational study using the data of patients <18 years of age in COVIREGI-JP, the COVID-19 registry in Japan. The patients were divided into two groups according to the timing of enrollment in the registry (pre-Delta VOC era, October 2020 to May 2021; and Delta VOC era, August to October 2021), and the clinical characteristics and outcomes were compared between the two groups. During the study period, 950 and 349 pediatric patients were registered in the pre-Delta VOC and Delta VOC eras, respectively. The median patient age was younger and the proportion of patients with underlying diseases was higher in the Delta VOC era than that in the pre-Delta VOC era (10.0 vs 7.0 years, P < 0.001, and 7.4% [n = 70] vs. 12.6% [n = 44], P = 0.004, respectively). Significantly more patients were admitted to the intensive care unit in the Delta VOC era than in the pre-Delta VOC era (1.4% [ n = 5] vs. 0.1% [n = 1], P = 0.006), but no patient in either group died or required mechanical ventilation or extracorporeal membrane oxygenation throughout the study period, suggesting that the overall outcomes in children with COVID-19 remained favorable even in the Delta VOC era in Japan.  相似文献   
10.
目的持续提升长三角地区(浙江省、江苏省、安徽省和上海市)献血者和血液安全管理水平。方法 2020年7月通过构建长三角地区献血者间隔期信息共享系统,为血站阻断因不到献血间隔而再次献血的献血者提供数据支撑和技术保障。结果长三角地区血站统一了献血者间隔期信息共享标准、开发了查询服务,实现了献血者间隔期信息共享。结论系统的建立降低了献血间隔期未到而再次献血的风险,进一步提升了长三角地区献血者和血液安全管理水平。  相似文献   
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