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排序方式: 共有580条查询结果,搜索用时 312 毫秒
571.
Can Liu Jiawei Zhang Yongbin Zeng Chun Huang Falin Chen Yingping Cao Siying Wu Donghong Wei Zhong Lin Yali Zhang Ling Zhang Jing Teng Zishun Li Guolin Hong Tianci Yang Huiming Ye Haijian Tu Yupeng Xiao Lishan Huang Caorui Lin Tianbin Chen Yanqin Deng Qishui Ou Jinming Li 《Journal of medical virology》2023,95(1):e28280
Severe acute respiratory syndrome coronavirus 2 breakthrough infection in highly vaccinated populations raises study on the effectiveness for inactivated vaccine, including effectiveness of the vaccine dose, the continuance of effectiveness, the effectiveness against severe/critical coronavirus disease 2019 and against secondary attacks. A population of 10 870 close contacts were investigated in a Delta variant's epidemic. The effectiveness of vaccination was estimated in a test-negative case–control study. In addition, serum was used to detect neutralizing antibodies, to explore their correlation to effectiveness. The vaccine effectiveness (VE) values were estimated for populations aged 12 years or older. The overall adjusted VE was 56.2% and a two-dose vaccine was more effective than a one-dose vaccine (56.7% vs. 43.8%). In addition, the population that got the second dose vaccine within 2 months showed higher VE than the population vaccinated for longer than 2 months (61.5% vs. 52.3%). Among the population who vaccinated 2 doses or within 2 months, a higher level of neutralizing antibodies was observed. For infected cases, vaccinated populations showed lower rates of transmission (2.63% vs. 4.36%). Further, those vaccinated cases, who were not found causing transmission, had a higher level of antibodies. The study provided a full view of the effectiveness of inactivated vaccines in a real-world setting. The time-related VE against infection and lower transmission of breakthrough vaccinated cases were observed, which may indicate that a necessity of a booster vaccine to maintain the effectiveness and high level of neutralizing antibody. 相似文献
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573.
目的:分析2021年北京市高中及以下学段入学新生肺结核筛查结果,为科学规范开展新生结核病筛查工作提供依据。方法:选取“北京市新生肺结核筛查系统”中2021年3804所学校高中及以下学段筛查信息记录完整的467 088名新生作为调查对象,收集其基本信息、肺结核可疑症状及密切接触史、结核菌素皮肤试验(tuberculin skin test, TST)结果,以及胸部X线摄片(简称“胸片”)检查结果等资料,并进行分析。结果:467 088名调查对象中,有肺结核可疑症状者占0.17‰(80/467 088),有肺结核密切接触史者占0.40‰(187/467 088)。69 519名调查对象进行了TST,阳性率为13.45%(9353/69 519)。寄宿制学校初中学段调查对象TST阳性率为11.07%(960/8673),明显低于高中学段调查对象的13.77%(8369/60 758),差异有统计学意义(χ2=52.927,P<0.001)。有肺结核可疑症状或密切接触史者TST中度及以上阳性率为12.64%(23/182),明显高于无肺结核可疑症状或密切接触史者的4... 相似文献
574.
《Vaccine》2023,41(33):4918-4925
The most common source of foodborne Salmonella infection in humans is poultry eggs and meat, such that prevention of human infection is mostly achieved by vaccination of farm animals. While inactivated and attenuated vaccines are available, both present drawbacks. This study aimed to develop a novel vaccination strategy, which combines the effectiveness of live-attenuated and safety of inactivated vaccines by construction of inducible self-destructing bacteria utilizing toxin-antitoxin (TA) systems. Hok-Sok and CeaB-CeiB toxin-antitoxin systems were coupled with three induction systems aimed for activating cell killing upon lack of arabinose, anaerobic conditions or low concentration of metallic di-cations. The constructs were transformed into a pathogenic Salmonella enterica serovar Enteritidis strain and bacteria elimination was evaluated in vitro under specific activating conditions and in vivo following administration to chickens. Four constructs induced bacterial killing under the specified conditions, both in growth media and within macrophages. Cloacal swabs of all chicks orally administered transformed bacteria had no detectable levels of bacteria within 9 days of inoculation. By day ten, no bacteria were identified in the spleen and liver of most birds. Antibody immune response was raised toward TA carrying Salmonella which resembled response toward the wildtype bacteria. The constructs described in this study led to self-destruction of virulent Salmonella enteritidis both in vitro and in inoculated animals within a period which is sufficient for the induction of a protective immune response. This system may serve as a safe and effective live vaccine platform against Salmonella as well as other pathogenic bacteria. 相似文献
575.
《Biomedical and environmental sciences : BES》2023,36(7):569-584
ObjectiveThis study aimed to assess the relationship between the body composition of children aged 3–5 years and breastfeeding status and duration.MethodsThe study was conducted using data from the National Nutrition and Health Systematic Survey for children 0–17 years of age in China (CNHSC), a nationwide cross-sectional study. Breastfeeding information and potential confounders were collected using standardized questionnaires administered through face-to-face interviews. The body composition of preschool children was measured using bioelectrical impedance analysis. A multivariate linear regression model was used to assess the relationship between breastfeeding duration and body composition after adjusting for potential confounders.ResultsIn total, 2,008 participants were included in the study. Of these, 89.2% were ever breastfed and the median duration of breastfeeding was 12 months (IQR 7–15 months). Among children aged 3 years, the height-for-age Z-score (HAZ) for the ever breastfed group was lower than that for never breastfed group (0.12 vs. 0.42, P = 0.043). In addition, the weight-for-age Z-score (WAZ) of the ever breastfed group was lower than that of the never breastfed group (0.31 vs. 0.65, P = 0.026), and the WAZ was lower in children aged 4 years who breastfed between 12 and 23 months than in those who never breastfed. Compared to the formula-fed children, the fat-free mass of breastfed infants was higher for children aged 3 years (12.84 kg vs. 12.52 kg, P = 0.015) and lower for those aged 4 years (14.31 kg vs. 14.64 kg, P = 0.048), but no difference was detected for children aged 5 years (16.40 kg vs. 16.42 kg, P = 0.910) after adjusting for potential confounders. No significant difference was detected in the weight-for-height Z-score (WHZ), body mass index (BMI)-for-age Z-score (BAZ), fat-free mass index, and body fat indicators in the ever breastfed and never breastfed groups and among various breastfeeding duration groups for children aged 3–5 years.ConclusionNo obvious associations were detected between breastfeeding duration, BMI, and fat mass indicators. Future prospective studies should explore the relationship between breastfeeding status and fat-free mass. 相似文献
576.
577.
Shelan Liu Jian Cai Yumin Li Lihong Ying Huan Li An Zhu Lin Li Haiying Zhu Shengcao Dong Ruyao Ying Ta-Chien Chan Hanting Wu Jinren Pan Yin Chen 《Journal of medical virology》2023,95(1):e28101
In 2019, an outbreak of pharyngoconjunctival fever (PCF) occurred at a swimming center in Zhejiang Province, China. A total of 97 (13.55%) of the 716 amateur swimmers had illnesses, with 24 patients (24.74%) hospitalized in the pediatric ward. Human adenovirus serotype 7 (HAdV-7) was isolated from one concentrated water from the swimming pool, and 20 of 97 positive cases without liver damage. This outbreak led to a nosocomial outbreak in the pediatric ward, in which 1 nurse had a fever and was confirmed to be adenovirus positive. The hexon, fiber, and penton genes from 20 outbreak cases, 1 water sample, and 1 nurse had 100% homology. Furthermore, 2 cases admitted to the pediatric ward, 2 parents, and 1 doctor were confirmed to be human coronaviruses (HCoV-229E) positive. Finally, all outbreak cases had fully recovered, regardless of a single infection (adenovirus or HCoV-229E) or coinfection of these two viruses simultaneously. Thus, PCF and acute respiratory disease outbreaks in Zhejiang were caused by the completely homologous type 7 adenovirus and HCoV-229E, respectively. The swimming pool water contaminated with HAdV-7 was most likely the source of the PCF outbreak, whereas nosocomial transmission might be the source of HCoV-229E outbreak. 相似文献
578.
Massively parallel sequencing can provide genetic data for hundreds to thousands of loci in a single assay for various types of forensic testing. However, available commercial kits require an initial PCR amplification of short-to-medium sized targets which limits their application for highly degraded DNA. Development and optimisation of large PCR multiplexes also prevents creation of custom panels that target different suites of markers for identity, biogeographic ancestry, phenotype, and lineage markers (Y-chromosome and mtDNA). Hybridisation enrichment, an alternative approach for target enrichment prior to sequencing, uses biotinylated probes to bind to target DNA and has proven successful on degraded and ancient DNA. We developed a customisable hybridisation capture method, that uses individually mixed baits to allow tailored and targeted enrichment to specific forensic questions of interest. To allow collection of forensic intelligence data, we assembled and tested a custom panel of hybridisation baits to infer biogeographic ancestry, hair and eye colour, and paternal lineage (and sex) on modern male and female samples with a range of self-declared ancestries and hair/eye colour combinations. The panel correctly estimated biogeographic ancestry in 9/12 samples (75%) but detected European admixture in three individuals from regions with admixed demographic history. Hair and eye colour were predicted correctly in 83% and 92% of samples respectively, where intermediate eye colour and blond hair were problematic to predict. Analysis of Y-chromosome SNPs correctly assigned sex and paternal haplogroups, the latter complementing and supporting biogeographic ancestry predictions. Overall, we demonstrate the utility of this hybridisation enrichment approach to forensic intelligence testing using a combined suite of biogeographic ancestry, phenotype, and Y-chromosome SNPs for comprehensive biological profiling. 相似文献
579.
《Journal of stroke and cerebrovascular diseases》2023,32(8):107128
BackgroundLeft ventricular assist devices (LVADs) improve survival in patients with end-stage heart failure but are associated with ischemic stroke and intracranial hemorrhage (ICH). The impact of LVAD-associated stroke on transplant candidacy and outcomes has not been characterized.MethodsAdult patients undergoing LVAD implantation at Cleveland Clinic between 2004 to 2021 were reviewed and patients who developed ischemic stroke or ICH were identified. Post-transplant survival analysis was performed between patients with LVAD-associated stroke vs. without.Results917 patients had an LVAD implantation of whom 244 (median age 57, 79% male) underwent subsequent transplant including 25 with prior LVAD-associated stroke. The 1- and 2-year survival after transplant in patients with LVAD-associated stroke were 100% and 95% respectively, compared with 92% and 90% in patients without stroke (p=0.156; p=0.323) Similarly, there was no difference in stroke incidence at 1- and 2 years after transplant between patients with LVAD-associated stroke (4% and 5%) and those without prior stroke (5% and 6%, p = 0.884; p=0.744).ConclusionsIn this single-center retrospective study, patients with LVAD-associated stroke were significantly less likely to undergo heart transplant, but those who underwent heart transplant had similar post-transplant outcomes as patients without history of LVAD-associated stroke. Given the similar outcomes seen in this population, history of LVAD-associated stroke should not be viewed as an absolute contraindication to subsequent heart transplant. 相似文献
580.
《Nutrition, metabolism, and cardiovascular diseases : NMCD》2023,33(7):1293-1307
AimsData on the association between nut consumption and prostate cancer risk are conflicting. Therefore, this systematic review and dose-response meta-analysis aimed to summarize available findings from observational studies on the associations of nut intake with risk of total, advanced, non-advanced, and fatal prostate cancers.Data synthesisWe searched the online databases of PubMed, Scopus, and Web of Science as well as Google Scholar using appropriate keywords to identify eligible articles up to September 2022. In total, 11 articles with a total sample size of 287,786 participants and 32,213 cases of prostate cancer were included in the current systematic review and meta-analysis. By comparing the highest and lowest intake of total nuts, pooled relative risks (RRs) and 95% confidence intervals (95% CIs) for total, advanced, non-advanced, and fatal prostate cancers were 0.94 (95% CI: 0.85–1.04, P = 0.22), 1.10 (95% CI: 0.98–1.24, P = 0.12), 0.97 (95% CI: 0.85–1.11, P = 0.69), 0.97 (95% CI: 0.79–1.18, P = 0.73), respectively, which indicated non-significant inverse associations for total, non-advanced, and fatal prostate cancers and a non-significant positive association for advanced prostate cancer. In the dose-response analyses, we found no evidence of a linear or non-linear association between total nut intake and prostate cancer risk. Data on other types of nuts, including walnut, tree nuts, peanut, and peanut butter, were not sufficient for performing a meta-analysis.ConclusionWe found no significant association between nut intake and risk of total, advanced, non-advanced, and fatal prostate cancer. Further studies are required to confirm our findings.Prospero registration codeCRD42022347094.Ethical approvalNot required. 相似文献