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We aimed to evaluate the association of the exposure to environmental tobacco smoke (ETS) during pregnancy and infancy with the risk of upper respiratory tract infections (URTI) in infants based on a Chinese birth cohort study. Among 4178 infants who constituted the final study population, 46.8% experienced URTI in their first year of life. The hazard ratios (HR) and 95% confidence intervals (CI) for the risk of URTI were assessed using Cox regression models. Compared with no ETS during pregnancy, continued ETS during pregnancy was independently associated with a higher risk of URTI (HR: 1.36, 95% CI: 1.13, 1.63) after adjustment for potential confounders and also associated with earlier occurrence of URTI (log-rank P = .002). The association remained consistent across the strata defined according to maternal age, number of siblings, sex, and breastfeeding. Exposure to ETS during infancy was associated with URTI only among infants who were breastfed for less than 12 months (P for interaction < 0.05).Furthermore, infants exposed to ETS during both pregnancy and infancy showed the highest HR of 1.46 (95% CI: 1.16, 1.85) for URTI. Efforts should be made to protect pregnant women and infants from the adverse effects of indoor and outdoor ETS.  相似文献   
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Today, individual's self-disclosure on the social network sites (SNS) have become a prevalent phenomenon. This study proposes a research model for investigating the beneficial effects of individual's self-disclosure on the social network sites (SNS). In this study, social support and online social well-being are seen as the beneficial effects of individual's self-disclosure on the SNS. Furthermore, this study examines whether self-disclosure increases social support and online social well-being. For developing a more parsimonious research model, this study chose self-disclosure and social support as second-order constructs. Self-disclosure is devised as a formative second-order construct that includes five components: amount, depth, honesty, intent, and valence. Social support is used as a reflective second-order construct comprising two factors: informational support and emotional support. In addition, this research also proposes that social support increase online social well-being. Further, online social well-being is hypothesized to positively affect the continuance intention in relation to the SNS. Data collected from 333 Facebook users provided support for all the hypotheses. Implications for theory and practice are discussed, and suggestions are made for future research.  相似文献   
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This paper studies the ozone treatment effect on degradation of aflatoxin B1 (AFB1) in corn with different moisture content (MC). The toxicity of the degradation products (DPs) of the ozone-treated AFB1-Contaminated Corn (ACC) was also evaluated using the human hepatocellular carcinoma cell line (HepG2) as model cells. The degradation rate of AFB1 in corn increases with ozone concentration and treatment time. The results showed that ACC with 13.47% MC was easier to be degraded by ozone than with 20.37% MC. Treated with 90 mg L−1 ozone for 20 min and 40 min, AFB1 in corn with 13.47% MC decreased from 83 μg kg−1 to 18.12 μg kg−1 and 9.9 μg kg−1, respectively, well meeting the China National Standard of AFB1 in corn (20 μg kg−1). In order to evaluate the safety of ozone used on ACC, the impacts of AFB1 as well as untreated and ozone-treated ACC with the same level of AFB1 content on HepG2's survival rate, morphology, and apoptosis were studied. The results showed that ACC had high cell toxicity while the toxicity of ozone-treated ACC had no significant difference with that of the AFB1-free culture solution. It is concluded that ozonation can quickly and effectively degrade AFB1 in corn and diminish ACC's toxicity, and therefore, ozonation is expected to be an effective, fast, and safe method for AFB1 degradation in ACC.  相似文献   
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Epidemiological and experimental studies provide supportive evidence that lutein, a major carotenoid, may act as a chemopreventive agent against atherosclerosis, although the underlying molecular mechanisms are not well understood. The main aim of this study was to investigate the effects of lutein on the alleviation of atherosclerosis and its molecular mechanisms involved in oxidative stress and lipid metabolism. Male apolipoprotein E knockout mice (n = 55) were fed either a normal chow diet or a high fat diet (HFD) supplemented with or without lutein for 24 weeks. The results showed that a HFD induced atherosclerosis formation, lipid metabolism disorders and oxidative stress, but noticeable improvements were observed in the lutein treated group. Additionally, lutein supplementation reversed the decreased protein expression of aortic heme oxygenase‐1 and increased the mRNA and protein expressions of aortic nicotinamide‐adenine dinucleotide phosphate oxidase stimulated by a HFD. Furthermore, the decreased mRNA and protein expression levels of hepatic peroxisome proliferator‐activated receptor‐α, carnitine palmitoyltransferase 1A, acyl CoA oxidase 1, low density lipoprotein receptors and scavenger receptor class B type I observed in mice with atherosclerosis were markedly enhanced after treatment with lutein. Taken together, these data add new evidence supporting the anti‐atherogenic properties of lutein and describing its mechanisms of action in atherosclerosis prevention, including oxidative stress and lipid metabolism improvements.  相似文献   
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目的 构建我国膳食无机砷致癌症及心血管疾病的疾病模型。方法 首先确立膳食无机砷导致的不同健康危害终点。根据我国人群相关疾病的流行病学数据,分别采用风险评估法和反事实分析法计算膳食无机砷暴露致癌症及心血管疾病的归因发病率、死亡率,结合疾病的伤残权重及病程等特点,构建膳食无机砷暴露致癌症及心血管疾病的疾病模型。结果 人群终身持续经膳食暴露于1.41 μg/(kg?d)无机砷时,引起皮肤癌、膀胱癌和肺癌的发病率分别为0.135%、0.010%以及0.034%,死亡率分别为0.015%、0.004%以及0.138%。人群终身持续经膳食暴露于1 μg/(kg?d)无机砷时,引起的心血管疾病发病率及死亡率分别为0.082%、0.025%。结论 疾病模型可用于计算食品污染物导致的疾病负担,对食品污染物的健康危害进行量化。  相似文献   
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《Food Control》2013,31(2):657-661
This paper presents the construction of amperometric biosensors for the detection of organophosphorus insecticides widely used in the treatment of olive trees. The systems are based on the immobilisation of acetylcholinesterase on screen-printed electrodes by bioencapsulation in a sol–gel composite. The enzyme activity was estimated by measuring the thiocholine produced by the enzymatic hydrolysis of the acetylthiocholine chloride using cobalt phtalocyanine as mediator. The developed devices have been used to carry out inhibition studies with three pesticides: malathion, methidathion and dimethoate (in their oxidized form), and tested using standard solutions and real samples of olive oil. These biosensors showed good operational stability as they maintained their initial analytical signal response during 10 successive measurements, and a good reproducibility with a relative standard deviation of 3%. The limits of detection of the developed devices were very compatible with the maximum residue limit tolerated by international regulations, they were as low as 10−9 M for the widely used pesticide malaoxon(oxidized malathion). The developed sensors were successfully used for the determinations of insecticides in real samples of olive oil.  相似文献   
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