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ObjectiveAlthough environmental lead exposure has decreased, several studies have shown that low-level lead exposure can result in adverse psychological symptoms. However, few studies have examined lead neurotoxicity in pregnant women. We investigated the association between lead exposure and psychological symptoms in pregnant women, and between socio-economic status and blood lead levels.MethodsBlood lead levels were measured in 17,267 pregnant women in the Japan Environment and Children’s Study. Odds ratios (ORs) for high blood lead levels were calculated using multinomial logistic regression. Psychological symptoms were assessed using the Kessler Psychological Distress Scale (K6). ORs for depression (K6 ≥ 13 or ≥5) were calculated using logistic regression with adjustment for potential confounders.ResultsThe geometric mean of whole blood lead levels was 0.58 μg/dl (range 0.14–6.75 μg/dl). Higher blood lead levels were associated with older age (OR 1.79, 9 5% confidence interval [CI] 1.46–2.19), unmarried status (OR 1.75, 95 % CI 1.31–2.33), lower household income (OR 1.76, 95 % CI 1.38–2.24), and lower educational attainment (OR 1.34, 95 % CI 1.20–1.48). The percentage of women with K6 scores ≥13 and ≥5 was 3 % and 28.2 %, respectively. There was no significant association between lead exposure and K6 score (K6 ≥ 13: OR 1.00, 95 % CI 0.76–1.32; K6 ≥ 5: OR 0.98, 95 % CI 0.88–1.09).ConclusionOur results indicate a small but significant association between higher blood lead levels and lower socio-economic status in a population with low blood lead levels, but no association between low-level lead exposure and psychological symptoms.  相似文献   
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Lead (Pb) is a heavy metal that is toxic to numerous physiological processes. Its use in industrial applications is widespread and results in an increased risk of human environmental exposure. The central nervous system (CNS) is most sensitive to Pb exposure during early development due to rapid cell proliferation and migration, axonal growth, and synaptogenesis. One of the key components of CNS development is the Gamma-aminobutyric acid (GABA)-ergic system. GABA is the primary inhibitory neurotransmitter in the adult brain. However, during development GABA acts as an excitatory neurotrophic factor which contributes to these cellular processes. Multiple studies report effects of Pb on GABA in the mature brain; however, little is known regarding the adverse effects of Pb exposure on the GABAergic system during embryonic development. To characterize the effects of Pb on the GABAergic system during development, zebrafish embryos were exposed to 10, 50, or 100 ppb Pb or a control treatment. Tissue up-take, gross morphological alterations, gene expression, and neurotransmitter levels were analyzed. Analysis revealed that alterations in gene expression throughout the GABAergic system and GABA levels were dose and developmental time point specific. These data provide a framework for further analysis of the effects of Pb on the GABAergic system during the excitatory phase and as GABA transitions to an inhibitory neurotransmitter during development.  相似文献   
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The paper describes the principles of cell impedance measurement method, which, unlike other impedance techniques used for cell examination, operates on-line. In order to present the capabilities of the proposed method, experimental results are shown. The conducted experiment was cyclic charging and discharging of the lead cell in 4.8 M H2SO4 with simultaneous impedance measurement. The variations of electric parameters, obtained as the result of impedance spectrums analysis, are highly correlated with the state of charge, as well as with the number of cycles.  相似文献   
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对 1 0例经静脉置入埋藏式心律转复除颤器 (ICD)的恶性室性心律失常患者进行随访 ,观察ICD的治疗效果。男 6例、女 4例 ,年龄 5 6.9± 1 3.3( 30~ 70 )岁。基础心脏病为冠心病 6例、心肌病 3例、先天性长QT综合征 1例。所有患者均经临床证实有室性心动过速或 /和心室颤动。ICD具有多项治疗及信息储存记忆功能。随访时通过体外程控仪调出ICD储存的资料进行分析。结果 :随访 2 9.3± 2 0 .4( 8~ 64)个月 ,7例患者分别接受了抗心动过速起搏、电转复及电除颤治疗。 2例患者因窦性心动过速、阵发性心房颤动 ,ICD给予误治疗。 1例患者术后 3年发生电极断裂。结论 :常规进行随访和设定合适的诊断和治疗参数 ,对保证ICD及时有效的治疗至关重要。  相似文献   
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血管内反推力牵引术拔除感染性起搏电极导管   总被引:7,自引:4,他引:7  
应用血管内反推力牵引术,经上腔静脉途径对9例病人的14根感染性起搏电极导管进行拔除。10根(71.4%)电极导管被完全拔除,不完全拔除2根(14.3%)。拔除失败的2根(1例)起搏电极导管经外科开胸术取出。平均随访9个月,感染被控制。提示血管内反推力牵引术是拔除感染性起搏电极导管和治疗起搏器植入术后顽固性感染的有效方法。  相似文献   
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