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11.
This study evaluated the influence of welding on pulmonary functions in welders. Spirometry tests were performed before and after work shift in 91 welders and 25 clerks (control group). We examined forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC ratio and forced expiratory flow 25%-75% (FEF 25–75). Significant differences were found for FVC and FEV1/FVC between welders and the control group in pre- and post-shift measurements (p < .001). In welders, smoking and nonsmoking habit had no significant effects on any pulmonary indices before or after shift. Work experience and fume concentrations also had no significant effects on the majority of spirometric indices (p > .05). Most welders had at least 1 of the respiratory symptoms. Significant differences were found between pre- and post-shift indices (as percentage of predicted values calculated with spirometer) and between the welders engaged in some welding tasks and the control group before work shift. This study documented work-related changes in pulmonary functions in the welders and marked drops in these functions without symptoms in some welders.  相似文献   
12.
2004年3月采集甘肃省武威市和内蒙古包头市正常良好天气、局地扬沙天气和沙尘暴天气的大气细颗粒物(PM2.5)样品,以不同浓度的细颗粒物悬液体外处理大鼠肺泡巨噬细胞后测定细胞内丙二醛(MDA)、谷胱甘肽(IgSH)及胞质游离Ca^2 含量,并观察不同处理时间的细胞存活率.研究结果表明:(1)沙尘暴与非沙尘暴PM2.5均使细胞内MDA和Ca^2 含量升高、GSH含量下降,且对细胞毒性存在时间.效应和剂量.效应关系,(2)PM2.5对各指标的影响仅与处理剂量有关,而与样品种类无关.沙尘暴期间大气PM2.5浓度很高,因而沙尘暴PM2.5的危害作用不可忽视。  相似文献   
13.
二氧化硫对大鼠肺泡巨噬细胞DNA的损伤作用   总被引:2,自引:0,他引:2  
运用单细胞凝胶电泳技术(又称彗星实验)研究了SO2动式吸入对雄性Wistar大鼠肺泡巨噬细胞DNA的损伤作用。结果表明,在SO2浓度为28.6,57.3,114.4ms/m^3的动式吸入染毒条件下,雄性大鼠肺泡巨噬细胞DNA拖尾长度分别为7.59,12.39,21.22μm,表明SO2可引起大鼠肺泡巨噬细胞DNA损伤,且随SO2吸入浓度的增加而加剧,呈明确的剂量效应关系,这意味着SO2具有引起哺乳动物肺泡巨噬细胞DNA突变的潜在危险,会造成机体的非特异性吞噬功能和抗肿瘤免疫监视作用的损伤。  相似文献   
14.
沙尘暴PM2.5水溶和有机成分对巨噬细胞的损伤   总被引:8,自引:1,他引:8       下载免费PDF全文
用超纯水或二氯甲烷从甘肃省武威市和内蒙古包头市采集的沙尘暴细颗粒物(PM2.5)中提取水溶成分和有机成分,于体外处理大鼠肺泡巨噬细胞4h,测定细胞谷胱甘肽(GSH)和丙二醛(MDA)含量、质膜ATP酶活性、膜表层和膜脂疏水区流动性、胞质内游离钙离子(Ca2+)浓度以及细胞培养液中乳酸脱氢酶(LDH)和酸性磷酸酶(ACP)活性.结果表明,沙尘暴PM2.5水溶成分可抑制质膜Ca2+-Mg2+-ATP酶、Na+-K+-ATP酶活性,降低质膜表层和膜脂疏水区流动性,增加胞质LDH外渗,并使细胞脂质过氧化作用增强、抗氧化能力减弱,但对ACP和Ca2+浓度影响不大;有机成分除引起胞质LDH渗漏、质膜Na+-K+-ATP酶活性下降外,对其它测定指标的影响无统计学意义.说明沙尘暴PM2.5水溶和有机成分均可对肺泡巨噬细胞产生毒性,其中水溶成分的毒性作用大于有机成分.  相似文献   
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16.
Congenital diaphragmatic hernia (CDH) can be associated with genetic or structural anomalies with poor prognosis. In isolated cases, survival is dependent on the degree of lung hypoplasia and liver position. Cases should be referred in utero to tertiary care centers familiar with this condition both for prediction of outcome as well as timed delivery. The best validated prognostic indicator is the lung area to head circumference ratio. Ultrasound is used to measure the lung area of the index case, which is then expressed as a proportion of what is expected normally (observed/expected LHR). When O/E LHR is < 25% survival chances are < 15%. Prenatal intervention, aiming to stimulate lung growth, can be achieved by temporary fetal endoscopic tracheal occlusion (FETO). A balloon is percutaneously inserted into the trachea at 26–28 weeks, and reversal of occlusion is planned at 34 weeks. Growing experience has demonstrated the feasibility and safety of the technique with a survival rate of about 50%. The lung response to, and outcome after FETO, is dependent on pre-existing lung size as well gestational age at birth. Early data show that FETO does not increase morbidity in survivors, when compared to historical controls. Several trials are currently under design. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
17.
为了探究不同暴露时间甲醛对小鼠哮喘模型肺氧化应激及IL-17表达的影响,用浓度为3.0 mg·m~(-3)的甲醛气体吸入染毒,同时将48只雄性Balb/c小鼠随机分为6组:(1)对照组(生理盐水组);(2)ovalbumin(OVA)致敏组;(3)0.5 h甲醛+OVA组;(4)1h甲醛+OVA组;(5)1.5 h甲醛+OVA组;(6)2 h甲醛+OVA组,以不同时间长度进行甲醛暴露,连续35 d。OVA致敏组、0.5 h甲醛+OVA组、1 h甲醛+OVA组、1.5 h甲醛+OVA组、2 h甲醛+OVA组均在第11、18及25天腹腔注射OVA致敏液(5 mg OVA+175 mg Al(OH)_3+30 mL生理盐水),第29~35天(共计1周)进行1%OVA雾化(30 min·d~(-1)),每日1次,诱发哮喘。第36天进行以下操作:取肺组织测定肺系数并制作肺匀浆,检测肺组织中活性氧自由基(ROS)、丙二醛(MDA)和还原型谷胱甘肽(GSH)的含量,并采用ELISA法检测肺组织中IL-17的水平。同时,采用HE染色法观察小鼠肺部气道的病理学变化。结果显示,在浓度为3.0 mg·m~(-3)的甲醛气体吸入染毒条件下,与对照组相比,1.5 h甲醛+OVA染毒组、2 h甲醛+OVA染毒组ROS、MDA、IL-17含量上升,具有统计学意义(P0.01)。同时,随着暴露时间长度的增加,小鼠肺部气道出现明显病理学变化。综上所述,每天2 h甲醛+OVA染毒能对小鼠肺造成损伤并恶化OVA对小鼠肺的损伤,产生炎症反应,并通过氧化应激反应介导。  相似文献   
18.
本文采集了重庆市三个污染轻重不同地区的雾水,并探讨了它们对体外PAM胞内ACP活性的影响。结果显示:污染严重的雾水对ACP活性呈现早期短暂抑制,中期明显激活,后期缓慢下降的峰形改变,在酶活性上升同时伴随酶染色区域在细胞内的扩散;污染轻的雾水仅有早期抑制作用而无刺激酶活性升高的表现。  相似文献   
19.
The widespread availability of high resolution ultrasound equipment and almost universal routine anatomy scanning in all pregnant women in the developed world has lead to increased detection of abnormalities in the fetal thorax. Already in the 1980s, large pleural effusions and significant macrocystic lesions in the fetus were easily detected on ultrasound. However, smaller lung tumours were often missed. Nowadays, fetal medicine centres receive many referrals for evaluation of fetal lung lesions, of which the most common are congenital cystic adenomatoid malformation and bronchopulmonary sequestration. Almost invariably, both the parents and the referring physicians experience anxiety after detection of large lung masses in the fetus. However, the vast majority of the currently detected fetal lung lesions have an excellent prognosis without the need for prenatal intervention. In the small group of fetuses in which the prognosis is poor, almost exclusively those with concomitant fetal hydrops and cardiac failure, several options for fetal therapy exist, often with a more than 50% survival rate. Indications, techniques, complications and outcomes of these interventions will be described in this review. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
20.
为了探讨高原地区尘肺患者死因特点及其规律,对青海省1955—2005年间诊断的2 942例尘肺患者有关资料进行了回顾性收集,并采用SPSS10.0软件进行统计分析。结果显示,青海省共有7种尘肺,其中矽肺和煤工尘肺占尘肺总数的93.88%。至2005年底,共有672例已死亡,尘肺病死率为22.84%。尘肺患者死亡年龄集中在40~49岁、50~59岁、60~岁组,占整个死亡总数的92.26%。平均死亡年龄为60.24岁,并且随着年代的推移而延长。尘肺患者平均寿命损失为15年。对死因分析后发现,前3位死因依次为:肺心病、尘肺和肺结核。探讨、分析及研究的结果表明,高原地区尘肺患者的首位死因为肺心病,提示在今后高原地区尘肺病防治工作中应加以重视。  相似文献   
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