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排序方式: 共有680条查询结果,搜索用时 15 毫秒
51.
目的预测不同年代参加接尘工作的大明矿矿工在若干年内尘肺发病人数。方法对某矿煤工尘肺和接尘矿工进行调查。以寿命表法计算不同年代参加接尘作业工人的尘肺累积发病率和年平均发病率;按期望寿命,根据工人的年龄构成进行煤工尘肺发病趋势的预测。结果该矿1959年前、1960—1964年、1965—1969年、1970—1979年四个不同年代参加接尘作业工人至2004年末的年平均发病率逐渐降低,四个年代的年平均发病率依次为0.40%、0.44%、0.06%、0.01%。其参加接尘作业工人预期发病人数分别为16.93人、7.03人、1.54人、2.18人,共27.69人,即28人。预测1964年前参加接尘作业的工人为主要发病人群,其发病人数占总发病人数的86.53%;发病人数主要集中在接尘后15年内,占总预期发病人数的79.05%。结论预测该矿未来尘肺发病人数逐渐减少,病例主要来自于1964年前参加接尘作业、年龄在60~74岁的工人;发病主要集中在今后15年内。 相似文献
52.
Li H Wang ML Seixas N Ducatman A Petsonk EL 《American journal of industrial medicine》2002,42(1):55-62
BACKGROUND: We investigated factors associated with the use of respiratory protection and explored the effectiveness of respirators among coal miners. METHODS: Between 1987 and 1992, respiratory symptoms, smoking, lung function, and dust exposures were assessed longitudinally among 185 underground bituminous coal miners. Self-reported use of respiratory protection was expressed as mean percent time wearing a respirator. RESULTS: Miners' respirator use increased with mean dust concentration, but decreased with tobacco consumption. Increasing age was associated with greater respirator use. Miners who had respiratory symptoms at the initial survey subsequently reported greater use of respirators. A significant protective association was found between the miners' respirator use and FEV(1) levels at both the initial and follow-up surveys. CONCLUSIONS: These results provide additional evidence that respirator use is protective of lung health. When respiratory protection programs are developed, factors that may affect respirator use behavior, such as age, smoking, and respiratory symptoms, should be considered. Future studies of respiratory health will need to consider workers' use of respiratory protection. 相似文献
53.
赵勤 《眼外伤职业眼病杂志》2006,28(4):279-280
目的 探讨45例(77眼)压力喷枪致眼外伤的病因、临床表现及治疗。方法 通过对45例(77眼)压力喷枪所致眼外伤的病因、临床表现及治疗进行分析。结果 压力喷枪致眼外伤引起异物伤、化学伤、眼挫伤,经过治疗45例(77眼)全部治愈,视力无明显影响。结论 针对异物伤,化学伤及眼挫伤进行治疗,收到良好的效果。 相似文献
54.
目的 了解I期尘肺病人体力能力和肺通气效率。方法 调查对象 14 3名 ,其中Ⅰ期煤工尘肺病人 6 4名 ,正常对照组 79名 ;所有对象进行心肺功能运动试验 ;运动设备为踏板 ,负荷方案采用非稳定状态的递增负荷法。结果 尘肺病人最大摄氧量 2 7.6 7ml·kg-1·min-1,显著低于正常人群 ;无氧阈位点和最大摄氧量水平位点的二氧化碳通气当量分别是 37.39和38.36 ,显著高于正常人群 ;6 4例尘肺病人中有 2 2人最大摄氧量小于 <2 5ml·kg-1·min-1。两组间无氧阈水平无显著性差别。结论 尘肺病人最大体力能力明显降低 ,通气效率明显降低 ,但体力耐力水平降低不明显 ;Ⅰ期煤工尘肺病人可胜任一般轻体力劳动 相似文献
55.
燃煤型氟骨症早期大鼠血清PTH、CT的变化 总被引:1,自引:2,他引:1
目的研究燃煤型氟骨症早期血清甲状旁腺激素(PTH)、降钙素(CT)的变化。方法将SD大鼠随机分为6组:对照、低氟、中氟加营养、中氟、高氟加营养、高氟组,每组34只,雌雄各半。各染毒组喂饲含不同比例的燃煤型病区煤烘玉米的饲料复制氟中毒动物模型。分2批以股动脉放血法处死动物,检查氟斑牙,测尿、骨、肾氟,骨密度(BMD),骨Ca、尿Ca,血清PTH、CT。结果(1)建成氟中毒动物模型:各染毒组均出现氟中毒,对照组正常。中毒严重程度随氟剂量增加而加重;氟剂量相同时,营养好,中毒程度轻。(2)燃煤型氟中毒对骨代谢相关激素的影响:高氟组血清PTH后期高于早期,差异有统计学意义(P<0.01)。说明染氟大鼠成骨活动增强,该指标变化较晚。血清CT各组早期无变化,后期低氟组和中营组升高,差异有统计学意义(P<0.05或0.01);低氟组高于高氟组,差异有统计学意义(P<0.05)。结论(1)骨转换活跃可能是燃煤型氟中毒骨病变发生发展的一个重要环节并且早期以成骨活跃为主;(2)尚不能认为血清PTH、CT是反映燃煤型氟骨症病情的早期指标;(3)降低摄氟量及改善营养状况,可缓解氟中毒病情。 相似文献
56.
煤尘对肺巨噬细胞具有一定毒性,使细胞存活率降低。煤尘中金属元素含量较低。经相关分析,八个煤矿煤尘的细胞存活率与各矿煤尘中的26种金属元素含量和游离SiO_2含量相关不显著。 相似文献
57.
BACKGROUND: Studies of dose-response relationships between respiratory outcomes at autopsy and coal dust exposure are limited. The Pathology Automation System (PATHAUT) database of South African miners, is one of the largest autopsy databases of occupational lung disease. This study described the prevalence of respiratory outcomes among South African coal miners at autopsy, and determined whether dose response relationships existed between emphysema and exposure. METHODS: Autopsies conducted from 1975 to 1997 on coal miners with exclusive coal mining exposure and having exposure duration information (n = 3,167) were analyzed from PATHAUT. Logistic regression was used to determine relationships between exposure and outcomes, controlling for race, smoking and age on a subset for whom smoking history was available (n = 725). RESULTS: The mean duration of exposure was 11.0 years. Most were black miners (75.3%) with significant differences in the mean ages of black and white miners (37.9 and 55.3 years, respectively). Only 22.9% of cases had information on smoking. The prevalence of silicosis, tuberculosis (TB), coal workers' pneumoconiosis (CWP), and moderate and marked emphysema were 10.7%, 5.2%, 7.3%, and 6.4%, respectively. All diseases, except TB, were associated with exposure duration. Black miners had 8.3 and 1.2 fold greater risks for TB and CWP, respectively, than white miners. White miners had an increased risk of 1.4 and 5.4 for silicosis and moderate to marked emphysema, respectively. In models unadjusted for age, and including smoking, moderate to marked emphysema was strongly associated with exposure duration (OR = 3.4; 95% CI = 1.9-5.9 for highest tercile of exposure duration). Exposure-related risk estimates were reduced when age was introduced into the model. However, age and duration of exposure were highly correlated, (r = 0.68) suggesting a dilution of the exposure effect by age. CONCLUSIONS: There were significant dose related associations of disease, including emphysema, with coal dust exposure. 相似文献
58.
Benavides F Conti CJ LaCava M Flores M Glasscock E Sternik G Gimenez-Conti IB Johnston DA Dunsford HA Goldstein LS Rodriguez LV 《Environmental and molecular mutagenesis》2003,41(4):300-308
Manufactured gas plant (MGP) residues, commonly known as coal tars, were generated several decades ago as a byproduct of residential and industrial gas production from the distillation of coal. Previous short-term exposure studies have shown MGP residues to be tumorigenic in mouse liver and lung. In order to gain further insight into carcinogenesis by complex mixtures of environmental chemicals containing known carcinogenic polycyclic aromatic hydrocarbons, we investigated mouse pulmonary tumors for loss of heterozygosity (LOH) as a result of multiple exposure to MGP residues. Twenty mouse lung adenomas produced in (C57BL/6 x C3H)F1 hybrid mice and manually microdissected were selected to examine genome-wide allelic losses at 58 microsatellite loci. Regions of chromosomes 1, 4, 5, 8, and 11 were affected in 30-40% of tumors. The elevated rates of allelic imbalance in these chromosomes may indicate the location of unknown tumor suppressor genes significant to neoplastic transformation in mouse lung tissues. Laser capture microdissection-based LOH analysis of pulmonary adenomas showed that contamination of nonneoplastic tissues was not masking the allelic losses in the manually microdissected tumor analysis. The low frequency of chromosome instability in these tumors, measured by means of inter-simple sequence repeat PCR, suggests the presence of discrete regions of LOH instead of extensive structural rearrangements. 相似文献
59.
60.
Xie Y Kondo M Koga H Miyamoto H Chiba M 《Environmental health and preventive medicine》2001,5(4):180-185
Objective To evaluate the effect of arsenic (As) on the porphyrin biosynthetic pathway, urine samples from patients with endemic chronic
arsenic poisoning were examined.
Subjects and Methods The subjects were 16 patients, who had been exposed to As from burning coal for 8 to 25 years, and 16 controls living in the
same region in Guizhou Province in southwest China. Concentrations of urinary As, porphyrins and ALA were determined by induced
coupled plasma mass spectrometry (ICP-MS), high performance liquid chromatography (HPLC) with a reversed-phase column and
fluorescence detector, and colorimetric spectrophotometry, respectively.
Results Concentrations of As in patients and controls, 184.40±200.04 and 86.82±64.20μ g/g creatinine (mean ±SD) respectively, were
significantly different (p<0.05). The concentrations of various kinds of urinary porphyrins, including isomers I and III of
coproporphyrin and pentacarboxylporphyrin, were determined. Positive correlations were observed between As and porphyrins
(e.g. total porphyrins, hexacarboxylporphyrin and coproporphyrin III) or between As and ALA in male and female patients. However,
porphyrin and ALA concentrations were not significantly different between the patients and the controls. Urinary porphyrin
concentrations in females were higher than those in males.
Conclusion Exposure to As from burning coal may influence porphyrin biosynthesis. 相似文献