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1.
《Health & place》2022
An accumulating body of evidence has associated exposure to greenspace with improved birth outcomes, including higher birth weight and lower risk of low birth weight; however, evidence on such association with in-utero fetal growth is scarce. We explored the influence of maternal exposure to residential greenspace and fetal growth in four INMA (Infancia y Medio Ambiente) Spanish birth cohorts (2003–2008), with 2,465 participants. Residential greenspace was characterised by the Normalised Difference Vegetation Index (NDVI) average across 100 m, 300 m, and 500 m buffers around the residence. Repeated ultrasound measurements of the abdominal circumference (AC), biparietal diameter (BPD), femur length (FL), and estimated fetal weight (EFW) were used. We created customised-generalised least squares models to evaluate associations of residential greenspace exposure on each fetal growth parameter, controlled for the relevant confounders. There were associations between the 500 m buffer and BPD, FL, and AC. We also found associations in the 300 m buffer and FL and AC. The associations in the 100 m buffer were null. Estimates were higher among participants with lower socioeconomic status. Mediation analyses found that air pollution might explain 15–37% of our associations. Mediation by physical activity was not observed. Greenspace exposure may be beneficial for fetal growth. 相似文献
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Kevin Kyung Ho Choi Santosh Sanagapalli 《World journal of gastrointestinal oncology》2022,14(3):568-586
Barrett's esophagus (BE) is the precursor to esophageal adenocarcinoma (EAC). Progression to cancer typically occurs in a stepwise fashion through worsening dysplasia and ultimately, invasive neoplasia. Established EAC with deep involvement of the esophageal wall and/or metastatic disease is invariably associated with poor long-term survival rates. This guides the rationale of surveillance of Barrett’s in an attempt to treat lesions at an earlier, and potentially curative stage. The last two decades have seen a paradigm shift in management of Barrett’s with rapid expansion in the role of endoscopic eradication therapy (EET) for management of dysplastic and early neoplastic BE, and there have been substantial changes to international consensus guidelines for management of early BE based on evolving evidence. This review aims to assist the physician in the therapeutic decision-making process with patients by comprehensive review and summary of literature surrounding natural history of Barrett’s by histological stage, and the effectiveness of interventions in attenuating the risk posed by its natural history. Key findings were as follows. Non-dysplastic Barrett’s is associated with extremely low risk of progression, and interventions cannot be justified. The annual risk of cancer progression in low grade dysplasia is between 1%-3%; EET can be offered though evidence for its benefit remains confined to highly select settings. High-grade dysplasia progresses to cancer in 5%-10% per year; EET is similarly effective to and less morbid than surgery and should be routinely performed for this indication. Risk of nodal metastases in intramucosal cancer is 2%-4%, which is comparable to operative mortality rate, so EET is usually preferred. Submucosal cancer is associated with nodal metastases in 14%-41% hence surgery remains standard of care, except for select situations. 相似文献
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《Vaccine》2022,40(8):1128-1134
BackgroundOver the last 2 decades, Haemophilus influenzae type a (Hia) has emerged as a significant cause of invasive disease in some geographic regions and populations. Recognition of the importance of Hia in the etiology of serious disease, particularly in young children, prompted the development of a new protein-capsular polysaccharide conjugate vaccine, similar in design to a vaccine against H. influenzae type b. At present, understanding of Hia immunology is incomplete; the immunological correlate of protection against invasive disease is unknown.MethodsOur objective was to study Hia antibody in children of various ages residing in a Canadian province with low incidence rates of invasive disease. The enzyme-linked immunosorbent assays were performed to quantify plasma IgG and IgM specific to Hia capsular polysaccharide in 133 children (3 months to 16 years).ResultsBoth anti-Hia IgG and IgM concentrations increased with age and were significantly higher in older children; a positive correlation between age and concentrations of Hia antibody was found. IgM antibody concentrations were significantly higher than IgG, with mean IgM concentrations over 10 times larger than IgG across all age groups.ConclusionsThe steady rise of naturally acquired, Hia-specific IgG and IgM concentrations in a pediatric population with low incidence rates of invasive Hia disease suggests the exposure to some cross-reactive environmental antigens as a major source of the antibody. However, the carriage rates of Hia in the region are unknown and further seroepidemiological studies are warranted. Although natural antibody may protect certain population groups against invasive disease, immunization of younger children will be essential to prevent serious infections if Hia continues to spread across North America. 相似文献
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背景 自然分娩是人类繁衍的正常生理过程,中国剖宫产率超出了世界卫生组织(WHO)提出的警戒线2倍多,而体育锻炼作为一种非药物性的健康干预方式,应引起相关部门的重视。 目的 运用Meta分析方法检验妊娠期体育锻炼对自然分娩影响的干预效果,并提出最优的锻炼方案。 方法 检索中国知网(CNKI)、中国生物医学文献服务系统(CBM)、维普网中文数据库和PubMed、EMBase、Web of Science、Cochrane Library英文数据库中有关妊娠期体育锻炼干预影响自然分娩结果的随机对照试验(其中干预组以体育锻炼干预为唯一干预方式,对照组进行常规护理知识教育或不进行有规律的体育锻炼),同时追踪相关系统评价所引用的参考文献,检索时间为1990—2021年。提取纳入文献资料,并对纳入文献进行方法学质量评价,采用RevMan 5.2软件进行Meta分析,运用GRADE工具对结局指标进行质量评价。 结果 共纳入30篇文献。Meta分析结果显示,干预组自然分娩发生率高于对照组〔RR=1.34,95%CI(1.28,1.40),P<0.000 01〕。亚组分析结果显示,锻炼开始节点对自然分娩的干预效果从高到低依次为:>24周、13~24周、≤12周;锻炼内容对自然分娩的干预效果从高到低依次为:盆底肌训练、运动课、体操、有氧运动、分娩球、瑜伽;锻炼频率对自然分娩的干预效果从高到低依次为:≥12次/周、3~5次/周、6~8次/周、9~11次/周;中等强度的锻炼较低强度的锻炼对自然分娩具有更大的影响;锻炼时长对自然分娩的干预效果从高到低依次为:30~<50 min/次、<30 min/次、≥50 min/次;锻炼周期对自然分娩的干预效果从高到低依次为:≤8周、17~24周、9~16周、25~34周。绘制体育锻炼干预对孕妇自然分娩影响的漏斗图,结果显示,漏斗图左右两侧基本对称,发表偏倚较小。运用GRADE工具对结局指标进行质量评价,结果显示,妊娠期体育锻炼影响自然分娩的评级为中等级。 结论 孕妇在妊娠期进行一定的体育锻炼对自然分娩结果具有良好的干预效果,且从妊娠期>24周开始锻炼、≥12次/周、30~<50 min/次、持续进行≤8周的中等强度的盆底肌训练、运动课、体操、有氧运动、分娩球以及瑜伽均对孕妇自然分娩的选择具有积极的影响。 相似文献
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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
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目的糖基化终末产物(AGEs)在糖尿病患者在角膜外伤或接受角膜手术时极易出现角膜上皮愈合延迟甚至不愈的过程中起着关键作用,本文研究维生素A(VA)对以糖基化终末产物AGE-BSA诱导角膜上皮细胞损伤的影响及可能的作用机制。方法以HCE-2细胞为研究对象,AGE-BSA为诱导剂,试剂盒检测VA对细胞凋亡率及线粒体膜电位的影响,荧光显微镜检测细胞内凋亡小体,Western blot检测相关的蛋白表达量。结果VA抑制AGE-BSA诱导的HCE细胞凋亡,调节AGEBSA引起的凋亡相关蛋白的变化。同时,VA与JNK的抑制剂同等程度的减少AGE-BSA诱导的JNK和NF-κB的磷酸化。结论VA可能通过抑制JNK介导的NF-κB炎症通路而起到减少AGE-BSA诱导的角膜上皮细胞凋亡的作用,可以作为糖尿病患者角膜上皮损伤的保护剂。 相似文献
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《International journal of hygiene and environmental health》2019,222(7):991-1000
IntroductionTraining fires may constitute a major portion of some firefighters’ occupational exposures to smoke. However, the magnitude and composition of those exposures are not well understood and may vary by the type of training scenario and fuels.ObjectivesTo understand how structure fire training contributes to firefighters' and instructors’ select chemical exposures, we conducted biological monitoring during exercises involving combustion of pallet and straw and oriented strand board (OSB) or the use of simulated smoke.MethodsUrine was analyzed for metabolites of polycyclic aromatic hydrocarbons (PAHs) and breath was analyzed for volatile organic compounds (VOCs) including benzene.ResultsMedian concentrations of nearly all PAH metabolites in urine increased from pre-to 3-hr post-training for each scenario and were highest for OSB, followed by pallet and straw, and then simulated smoke. For instructors who supervised three trainings per day, median concentrations increased at each collection. A single day of OSB exercises led to a 30-fold increase in 1-hydroxypyrene for instructors, culminating in a median end-of-shift concentration 3.5-fold greater than median levels measured from firefighters in a previous controlled-residential fire study. Breath concentrations of benzene increased 2 to 7-fold immediately after the training exercises (with the exception of simulated smoke training). Exposures were highest for the OSB scenario and instructors accumulated PAHs with repeated daily exercises.ConclusionsDermal absorption likely contributed to the biological levels as the respiratory route was well protected. Training academies should consider exposure risks as well as instructional objectives when selecting training exercises. 相似文献