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aVR sign as a risk factor for life-threatening arrhythmic events in patients with Brugada syndrome 总被引:2,自引:0,他引:2
BACKGROUND: Risk stratification in Brugada syndrome (BS) is controversial, especially in asymptomatic individuals. OBJECTIVE: The aim of this study was to evaluate the significance of lead aVR in patients with BS. METHODS: Twenty-four patients with the electrocardiogram pattern of BS (24 male, mean age 32.1 +/- 13.6 years) and 24 healthy age- and gender-matched controls were studied. RESULTS: Thirteen patients were symptomatic. The R-wave amplitude or R/q ratio in lead aVR was significantly greater in patients experiencing a recurrence compared with those who did not. The aVR sign was defined as R wave >/= 0.3 mV or R/q >/= 0.75 in lead aVR. Most of the recurrences (78%) were in patients with present aVR sign; 84% of BS patients with present aVR sign had events during follow-up. In contrast, only 27% of BS patients with absent aVR sign had events during follow-up. CONCLUSION: Our study shows significant correlation between a prominent R wave in lead aVR (aVR sign) and risk for development of arrhythmic events in BS. In the presence of BS, prominent R wave in lead aVR may reflect more right ventricular conduction delay and subsequently more electrical heterogeneity, which in turn is responsible for a higher risk of arrhythmia. 相似文献
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目的 :了解本地区脐血铅水平现状及其妊娠结局与妊娠并发症 ,新生儿体格发育及神经行为发育的关系 ,并探讨脐血铅与环境因素的关系。方法 :采用 HB2 10 0原子吸收光谱仪用原子吸收法测定 178例经剖宫分娩的新生儿脐带血水平 ,同时观察孕妇妊娠与分娩期有无合并症与并发症 ,并于新生儿出生后即刻测量体重、身长 ,2 4 h内测量头围、胸围和腹围 ,采用神经行为发育量表 ,对出生后 4 2 d的 5 0例婴儿进行神经行为发育评分。同时对产妇家庭环境等相关因素进行问卷调查。结果 :178例脐血铅最高值 12 2 μg/ L,最低值 1μg/ L,中位数 36 μg/ L,脐血铅≥ 10 0 μg/ L 者 6例 ,占3.33%。脐血铅水平与妊娠并发症无明显相关性 ,与新生儿体格发育及神经行为发育评分无明显相关性。新生儿血铅水平与环境因素 (家庭住址、居室新旧、家庭经济情况、职业等 )差异有显著性 ,P<0 .0 5。结论 :本组脐血铅水平与孕期并发症及新生儿体格发育及神经行为发育评分无明显关系。脐血铅水平与环境因素有关。 相似文献
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宝鸡市市区268名儿童铅中毒情况的相关因素分析 总被引:3,自引:0,他引:3
吕菊红 《临床和实验医学杂志》2006,5(3):223-224
目的研究宝鸡市市区儿童铅中毒相关因素,提出干预对策.方法严格按照有关要求,采用原子吸收石墨炉法进行血铅测定;对测试血铅高于100 μg/L的儿童通过问卷调查相关影响因素.结果 268名儿童血铅水平平均为150 μg/L ,其中血铅水平≥100 μg/L者占79.85%.结论宝鸡市市区属于工业城市,儿童铅中毒检出率较高,应引起高度重视. 相似文献
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Jim-Shoung Lai T.-N. Wu Saou-Hsing Liou Chen-Yang Shen Chiam-Fang Guu Kquei-Nu Ko Chi. Hsueh-Yun P.-Y. Chang 《International archives of occupational and environmental health》1997,69(4):295-300
Objective: To examine the relationship between ambient lead levels and blood lead levels and to explore the modifiers of the relationship
between ambient lead and blood lead. Method: A cross-sectional study was conducted in two lead battery factories. Blood lead level and ambient lead concentration were
measured for each participant concurrently. A structured questionnaire was administered to collect sociodemographic characteristics
and occupational history. Design: Biological and personal environmental measurements of 219 lead-exposed workers were analyzed by both simple and multiple linear
regression. A regression model was selected for interpretation. Results: A high correlation (r=0.62) between ambient lead (PbA) and blood lead (PbB) was observed. In addition, numerous factors, including age, sex, alcohol
consumption, personal hygiene practice and type of lead exposure, were also found to influence blood lead levels. Although
PbB was highly correlated with PbA, blood lead level may not be effectively lowered by reducing ambient lead level. Based
on the regression coefficients, improvement of hygienic practice was more effective at lowering PbB than reducing ambient
lead level. Good hygienic practice may be the preferential way to reduce lead exposure in current conditions. Conclusion: Education of correct work practice may be more important than engineering control in the developing countries to lower blood
lead levels in lead battery factories.
Received: 28 May 1996/Accepted: 30 August 1996 相似文献
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铅性肾病的流行病学分析 总被引:20,自引:11,他引:9
我们检查了铅接触人员1023名,发现铅性肾病84例,患病率8.2%。女性34例(7.2%),男性50例(9%),男女铅性肾病患病率无显著性差异。印刷厂空气铅浓度平均0.0069mg/m3,蓄电池厂为0.1005mg/m3,铅矿为0.5mg/m3。铅性肾病患病率分别为4.73%,8.3%和28.57%(P<0.005)。分析铅性肾病患病率与年龄和铅接触年限的关系。年龄小于30岁,~40岁,~50岁和大于50岁者,铅性肾病患病率分别为5.5%,8.6%,12.1%,和15.6%(P<0.05)。铅接触年限小于10年,~20年和大于20年者,铅性肾病患病率分别为6.6%,9.9%和13.1%(P<0.05)。 相似文献
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Kazuyuki Terayama Naoki Maehara Makoto Muratsugu Mikio Makino Kohtaroh Yamamura 《Toxicology》1986,40(3):259-265
Lead often affects the erythrocyte membrane. The relationship between the changes in erythrocyte membrane and the anemia caused by lead is still unclear. Initially, the effect of lead injected intraperitoneally on the electrophoretic mobility of rat erythrocytes was investigated in order to study the relationship between them. As indices of lead exposure, hemoglobin (Hb) levels, hematocrits (Ht), δ-aminolevulinic acid dehydratase (ALA-D) activities and blood lead (blood Pb) levels in the injected rats were also examined. Exposure to lead significantly decreased the mobility of rat erythrocytes. The changes in mobility seemed to be less sensitive than those in ALA-D activity, however, the decreases in mobility were simultaneous with or prior to those in Hb level and Ht. The decreases in mobility were evident to some extent below a blood Pb level of 100 μg/100 ml and generally present at a level of 100 μg/100 ml and over. In the rats exposed to lead a significant negative correlation was found between the mobilities and the logarithms of blood Pb level. 相似文献