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21.
目的探究肿瘤坏死因子-α(Tumornecrosis factor-α,TNF-α)-308基因对导管相关性脓毒症(Catheter related sepsis,CRS)患者病情的影响,旨在为临床治疗CRS提供科学依据。方法选取2017年7月-2018年10月于浙江大学医学院附属杭州市第一人民医院接受治疗的86例CRS患者为研究对象,按照是否并发多器官功能障碍综合征将患者分为试验组和对照组,对照组共48例,未并发多器官功能障碍综合征,试验组共38例,并发多器官功能障碍综合征,分析两组患者TNF-α-308基因多态性差异,使用多因素Logistic回归分析CRS患者并发多器官功能障碍综合征的危险因素。结果试验组GA基因型频率34.21%、AA基因型频率50.00%、高G等位基因频率18.42%均高于对照组,GG基因型频率52.63%、A等位基因频率28.95%均低于对照组,差异均具有统计学意义(P<0.05);多因素Logistic回归分析结果显示,低GG基因型频率、低G等位基因频率、高GA基因型频率、高AA基因型频率、高A等位基因频率是CRS患者并发多器官功能障碍综合征的危险因素(P<0.05)。结论TNF-α-308基因与CRS患者病情密切相关,GG基因型频率和G等位基因频率降低,GA基因型频率、AA基因型频率、A等位基因频率升高会加重患者的病情,增加多器官功能障碍综合征的发生风险,临床上应该加以重视。  相似文献   
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Vegetation water content (VWC) is the key input parameter for a soil moisture retrieval algorithm based on microwave remote sensing, and VWC uncertainty can limit the estimated accuracy of soil moisture. There has been little research on VWC algorithm development and validation in China, and the uncertainty of the VWC estimation method has not been well evaluated. Therefore, the aim of this study is to evaluate the uncertainty of the VWC estimation method used in the SMAP (Soil Moisture Active Passive) algorithm on three spatial scales (the point-scale, 30 m scale, and 1 km scale) for maize in northeast China. Results from three ground experimental datasets showed that the SMAP VWC estimation method was strongly biased with an average overestimation of 1.16 kg m?2,1.04 kg m?2, and 1.13 kg m?2 for the point-scale, 30 m scale, and 1 km scale respectively, and maximum bias occurred in the mid-stage of maize. Also, a new power relationship between NDVI (Normalized Difference Vegetation Index) and VWC was proposed for the 30 m scale based on Sentinel 2 NDVI and field VWC values from 2017 experiment, with respective R2 (coefficient of determination) and Root Mean Squared Error (RMSE) values of 0.80 and 0.67 kg m?2. The results confirmed that this power relationship was still suitable for VWC estimation at the 1 km scale, and it has smaller bias than the original SMAP VWC method. Future work will be carried out to evaluate the applicability of this VWC estimation method over a lager region. It is expected that it can improve the accuracy of soil moisture by providing high precision VWC input parameters.  相似文献   
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Lung and female breast cancers are highly prevalent worldwide. Although the association between exposure to ambient fine particulate matter (PM2.5) and lung cancer has been recognized, there is less evidence for associations with other common air pollutants such as nitrogen dioxide (NO2) and ozone (O3). Even less is known about potential associations between these pollutants and breast cancer. We conducted a population-based cohort study to investigate the associations of chronic exposure to PM2.5, NO2, O3 and redox-weighted average of NO2 and O3 (Ox) with incident lung and breast cancer, using the Ontario Population Health and Environment Cohort (ONPHEC), which includes all long-term residents aged 35–85 years who lived in Ontario, Canada, 2001–2015. Incident lung and breast cancers were ascertained using the Ontario Cancer Registry. Annual estimates of exposures were assigned to the residential postal codes of subjects for each year during follow-up. We used Cox proportional-hazards models adjusting for personal- and neighborhood-level covariates. Our cohorts for lung and breast cancer analyses included ~4.9 million individuals and ~2.5 million women, respectively. During follow-up, 100,146 incident cases of lung cancer and 91,146 incident cases of breast cancer were diagnosed. The fully adjusted analyses showed positive associations of lung cancer incidence with PM2.5 (hazard ratio [HR] = 1.02 [95% CI: 1.01–1.05] per 5.3 μg/m3) and NO2 (HR = 1.05 [95% CI: 1.03–1.07] per 14 ppb). No associations with lung cancer were observed for O3 or Ox. Relationships between PM2.5 and NO2 with lung cancer exhibited a sublinear shape. We did not find compelling evidence linking air pollution to breast cancer.  相似文献   
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目的探讨佛山市乙肝母婴阻断工作中存在的问题,为完善进一步工作提供思路。 方法采用队列研究的方法,以2017年佛山市HBsAg阳性产妇13 672例及其所分娩13 982例活产儿为研究对象,通过回顾性病历采集及前瞻性的随访追踪的方法,全面了解影响乙肝母婴阻断工作的主要因素。 结果2017年佛山市产妇HBsAg阳性率为10.14%,感染孕妇中HBeAg阳性率为24.13%,孕期HBV DNA检测率约5%,其中抗病毒治疗63例;新生儿乙肝免疫球蛋白接种率为99.84%;婴儿在出生后1年内完成乙肝疫苗三针接种的比率为81.71%,在完成三针乙肝疫苗接种的儿童中按照0-1-6程序接种的比率为62.65%;母婴阻断结果追踪率为40.16%,追踪儿童中母婴阻断失败34例,失败率为0.61%;产妇年龄低、HBeAg阳性、HepB未全程及规范接种是母婴阻断失败的危险因素(P<0.05)。儿童明确未检测的主要原因是拒绝检查、不知道要检查、提前检查和检测未提供结果,占99.07%。 结论加强信息沟通及健康教育,落实乙肝病毒感染产妇孕期DNA检测及抗病毒治疗,提高儿童乙肝疫苗的规范接种率,将暴露儿童的乙肝两对半检测纳入儿童保健管理工作,是实现全市乙肝母婴零传播的重要措施。  相似文献   
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Porocarcinoma is an unusual, locally aggressive and potentially fatal neoplasm. Several cutaneous malignancies have been described in association with porocarcinoma, including squamous cell carcinoma, basal cell carcinoma and tricholemmal carcinoma. Previous reports have indicated that the occurrence of malignant tumours in combination with porocarcinoma is extremely rare, in particular with regard to Bowen disease (BD). We report an uncommon case of porocarcinoma occurring synchronously in a single BD lesion in a 63‐year‐old woman with multiple BD lesions. The clinical and histological findings confirmed this diagnosis.  相似文献   
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