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61.
报道福建某盐场从事日晒海盐生产人工机体内高镁对心血管系统的影响,通过现场空气、饮水、主良的镁含量测定,并对进入机体途径进行分析,得出空气、卤水接触、饮水为机体镁增高的主要来源。不同对象头发镁含量测定结果显示,以接触卤水、劳动强度大的盐工最高,并随机体内镁含量增高,出现血压偏低、心率减慢、心电图P-R间期延长、QRS波增宽、T波高尖等机体高镁反应,与临床高镁血症相似。 相似文献
62.
In a group of 43 smelter workers exposed to inorganic arsenic dust for 13-45 years, nerve conduction velocities (NCVs) were significantly lower in two peripheral nerves as compared with matching referents. With multivariate data analysis, a significant negative correlation was found between cumulative absorption of arsenic and NCV in four examined nerves and the sural amplitude. Clinical symptoms of neuropathy and other symptoms related to arsenic exposure were moderate, though the difference between the groups was significant. The mean total absorption of arsenic was calculated to be less than 5 g, and the maximal absorption about 20 g. These data indicate that the adverse effect of arsenic on the peripheral nerves is dependent on long-term exposure rather than on short-term fluctuations in exposure levels. © 1994 Wiley-Liss, Inc. 相似文献
63.
采用大蒜对焦炉工在不脱离生产情况下,进行为期半年的实验服用,观察其对生物膜损伤和细胞免疫功能的保护作用。结果表明:服用大蒜制剂后焦炉工的唾液酸(SA)和脂质过氧化(LPO)比服用前降低(P<0.01),谷胱甘肽过氧化物酶(GSH-Px)有所增高,但P>0.05,在细胞免疫方面,表现为酸性α-醋酸萘酯酶(ANAE)和活性E-花环%(Ea)的增高(P<0.01)。对照组的细胞免疫功能及生物膜损伤情况均无改善,提示:大蒜对焦炉工的生物膜和细胞免疫均有一定的保护作用。 相似文献
64.
目的了解工艺改进后金属酸洗岗位职业危害因素及浓度降低效果,控制岗位人员职业危害因素接受量,预防职业病的发生。方法通过对某钢铁厂金属酸洗车间工艺改进前后酸洗和天车操作两个岗位职业危害因素监测结果进行对比、分析,确定工艺改进对控制岗位职业危害的效果。结果天车操作室:硫酸雾合格率由60.2%上升到88.9%,盐酸雾合格率由63.0%提高到100%;酸洗操作岗位:硫酸雾合格率由37.0%上升到87.9%,盐酸雾合格率由49.0%提高到99.1%。经统计学分析,工艺改进前与工艺改进后硫酸雾、盐酸雾总体合格率差异均有显著性(P〈0.05),说明工艺改进后主要岗位职业危害因素减低的合格率均有较大提升。结论工艺改进对控制酸洗岗位职业危害效果明显。 相似文献
65.
Frank de Vocht Berna van-Wendel-de-Joode Hans Engels Hans Kromhout 《Magnetic resonance in medicine》2003,50(4):670-674
The interactive use of magnetic resonance imaging (MRI) techniques is increasing in operating theaters. A study was performed on 17 male company volunteers to assess the neurobehavioral effects of exposure to magnetic fields from a 1.5 Tesla MRI system. The subjects' neurobehavioral performances on a neurobehavioral test battery were compared in four 1-hr sessions with and without exposure to magnetic fields, and with and without additional movements. Adverse effects were found for hand coordination (-4%, P < 0.05; Pursuit Aiming II) and near visual contrast sensitivity (-16% and -15%, P < 0.10; Vistech 6000). The results from the remaining tests were inconclusive due to a strong learning effect. No additional effect from gradient fields was detected. The results indicate that working near a 1.5 Tesla MRI system may lead to neurobehavioral effects. Further research is recommended, especially in members of operating teams using interactive MRI systems. 相似文献
66.
护理人员工作中被针刺伤调查及对策 总被引:129,自引:14,他引:115
目的:了解护理人员被针刺伤的情况,为采取职业防护措施提供科学依据。方法:采用问卷调查法调查护理人员被针头伤的有关情况。结果:不同职称护理人员被针刺伤的情况存在差异高度显著性,P<0.01;不同科室护理人员被针刺伤的操作环节比较均存在差异高度显著性,P<0.01,绝大多数护理人员对针刺伤后的处理不规范。结论:护理人员应主动增强职业防护意识,加强职业防护管理;改进废弃的一次性医疗用品管理方法和尽快采用防刺性护理用具。 相似文献
67.
This retrospective analysis reviews the clinical experience of a major urban referral hospital with diffuse malignant pleural mesothelioma during the 14-year period from 1973 through 1986. Seventy-five cases of definite or equivocal mesothelioma were identified. There were four cases of primary malignant peritoneal mesothelioma, seven cases of benign fibrous mesothelioma, and 64 cases of diffuse malignant pleural mesothelioma. In 43 cases (67%) of diffuse malignant pleural mesothelioma, there was historic evidence of asbestos exposure. In 21 cases (33%), there was no known history of asbestos exposure. An increase in annual incidence of diffuse malignant pleural mesothelioma was observed over the study period, from three cases in 1973 to ten cases in 1986. Despite greater awareness of this disease, the diagnosis remains a difficult one to establish given the nonspecific symptoms, signs and radiographic appearance, variable histologic appearance, and poor diagnostic sensitivity and specificity of thoracentesis and closed pleural biopsy. Thoracotomy, thoracoscopy, and CT-guided needle biopsies gave higher yields and are the diagnostic measures of choice when diffuse malignant pleural mesothelioma is suspected. 相似文献
68.
69.
Jasminka Godnic-Cvar 《International archives of occupational and environmental health》1995,67(2):79-84
A methodological overview is provided on the important question of how to confirm occupational asthma in routine work. Recent knowledge gained in immunology and occupational allergy has been utilized, supplemented by an overview of recent publications on the diagnosis and pathophysiology of occupational asthma. The aim of the paper is to facilitate decision making for an investigator dealing with individual cases of occupational asthma. Moreover, by presenting stepping-stones in the diagnostic cascade, the author hopes to encourage the less experienced to conduct a comprehensive and cause-oriented diagnostic procedure. Methods which are being worked on at present (standardization) are discussed in more detail. Finally, the research goals in the understanding, confirmation, and prevention of occupational asthma are listed. 相似文献
70.
Louise Nadon Jack Siemiatycki Ron Dewar Daniel Krewski Michel Grin 《American journal of industrial medicine》1995,28(3):303-324
Polycyclic aromatic hydrocarbons (PAHs) demonstrate carcinogenic activity in animal models. Although some epidemiologic studies have implicated PAHs as risk factors for human cancer, the evidence reported to date has not been consistent. The purpose of this report is to describe the associations between occupational exposure to PAHs in the workplace and each of 14 types of cancer. A population-based, case-control study was carried out in Montreal to investigate associations between a large variety of environmental and occupational exposures on the one hand, and several types of cancer on the other. A detailed job history was obtained from each subject along with information on a number of potential confounders. Each job history was reviewed by a team of experts, who used this information to construct a corresponding history of occupational exposures. Among the PAH exposures considered were benzo(a)pyrene (B(a)P) and five categories of PAHs defined on the basis of the source material, namely, wood, petroleum, coal, other sources, and any source. Altogether, 3,730 cancer patients and 533 population controls were interviewed and their job exposure histories coded. For each of 14 types of cancer analyzed, three control groups were available: other cancer patients, population controls, and the pooled set of cancer and population controls. The associations between 14 cancer types and 6 PAH exposures were analyzed using logistic regression methods. For most types of cancer evaluated, there was no evidence of excess risk due to PAHs at the levels encountered in the occupations in which PAH exposure has been prevalent in the Montreal area. For a few cancer sites–the esophagus, the pancreas, and the prostate gland–there were suggestions of excess risk; these observations are noteworthy hypotheses for further investigation. For lung cancer, there appeared to be an increased risk due to PAHs among nonsmokers and light smokers, but not among heavy smokers. 相似文献