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51.
Fishbein L 《Environmental toxicology and pharmacology》1996,2(2-3):193-195
At the present time multiple chemical sensitivities (MCS) is generally acknowledged to be a poorly understood clinical syndrome which is exhibited by individuals exposed to low levels of exposure to environmental agents that the general population tolerate quite well. A wide range of individual symptoms (typically multiple and related to neurologic, endocrine/metabolic, and immunological, often occurring simultaneously) are displayed by MCS patients. Questions concerning whether or not MCS is a real clinical condition, a form of psychiatric illness or a combination of both remain to be unambiguously clarified. 相似文献
52.
INTRODUCTION: There is a paucity of data comparing injured pediatric patients transported by helicopter emergency medical services (HEMS) with patients transported by ground ambulance. The purpose of this study was to compare HEMS pediatric trauma patients to: 1) pediatric patients transported by ground to an urban level-1 trauma center (TC), and; 2) a similar cohort of adult patients. The managed-care consequences of these comparisons are highlighted. METHODS: All trauma patients flown directly from the scene by HEMS from January 1, 1990, to April 30, 1993, were compared to a cohort of trauma patients arriving by ground advanced life support (ALS). All patients were transported to the same level-1 TC. The data collected included the mechanism of injury and the prehospital procedures performed, the injury severity score (ISS), and outcome. RESULTS: There was no difference in the ISS between the HEMS (n = 216) and ground ALS (n = 355) pediatric patients (16.8 vs 17.1; p = 0.55). Adult HEMS patients (n = 202) had significantly higher ISS than did injured adults (n = 1652) transported by ground (18.0 vs 13.6; p < 0.0001). Overall, trauma patients transported by air directly from the scene have a higher ISS than patients transported by ground (17.5 vs 13.6; p < 0.001). CONCLUSIONS: Pediatric patients transported by HEMS were as severely injured as those transported by ground, in contrast to adult patients. We conjecture that since trauma triage schemes classically focus on adults, ground personnel are more selective about which patients are flown to a TC, and less selective for pediatric patients. Trauma centers and HEMS programs should develop pediatric trauma triage protocols that do not overemphasize physiologic parameters. 相似文献
53.
W. Zschiesche K. -H. Schaller D. Weltle 《International archives of occupational and environmental health》1992,64(1):13-23
Summary Soluble barium (Ba) compounds are well-known toxicants. Intoxications are mainly known in an acute form from casual or suicidal oral ingestion. No scientifically based data are available on possible health effects of inhalative exposure to soluble Ba salts at the workplace. Therefore, we investigated 18 welders in an interventional study over 1 week. They performed welding of Ba-containing stick electrodes and self-shielded flux cored wires under conditions similar to real working conditions. The welding fumes contained 31%–37% Ba, more than 90% of which was soluble in acids. Without appropriate preventive measures, a high rate of measurements exceeded the TLV values for total welding fumes of 5 mg/m3 and for soluble Ba of 0.5 mg/m3. The median fume concentrations were 13.2 mg/m3 in stick electrode welding and 12.3 mg/m3 in flux cored wire welding. The median Ba concentrations were 4.4 and 2.0 mg/m3 respectively. An integrated exhaust system built into the gun proved to be efficient in flux cored wire welding. The internal exposure to Ba reached median urine levels up to 101.7 g/l (normal: below 20 g/l) and median plasma concentrations of up to 24.7 g/l (normal: below 8 g/l). No health impact on the welders could be proven, but hypokalemia may have occurred as a result of the Ba exposure. 相似文献
54.
Study of preclinical changes in workers exposed to inorganic mercury in chloralkali plants 总被引:6,自引:0,他引:6
Summary The aim of the present work was to clarify the question of preclinical changes of Hg intoxication (micromercurialism) in man. The study to detect these disorders was performed on 39 chloralkali plant workers who had been exposed to mercury for more than 7 years. The ambient air, urine and blood values of the last few years were determined in extensive measurements by various methods and related to one another. The average ambient air concentrations were clearly below the currently applicable threshold limit value (German MAK) of 0.1 mg/m3. For the purpose of clarifying the mentioned question of preclinical changes of intoxication, the exposed persons were subjected to psychomotor-function examinations and compared with a group of nonexposed persons. The blood pressure and pulse frequency values of both groups were also determined and compared with one another. No significant differences between the two groups of persons examined were detectable.Presented at the 18th Congress of the Deutsche Gesellschaft für Arbeitsmedizin in Frankfurt, 24th May 1978 相似文献
55.
Szucs P Allegra JR Fields LA Grabiner FR Lavery R Prusik T Tortella B 《Air medical journal》2000,19(1):19-21
INTRODUCTION: The safety and efficacy of medications stored on air medical helicopters may be adversely affected by extreme temperatures. The purpose of this study was to determine whether temperatures inside an air medical helicopter drug box were within the U.S. Pharmacopeia recommendations for controlled room temperature. This is defined as a temperature between 15 degrees and 30 degrees C (59 degrees and 86 degrees F) with a mean kinetic temperature of less than 25 degrees C (77 degrees F). An additional goal was to determine whether time/temperature indicator labels can reliably monitor mean kinetic temperatures. METHODS: Temperatures were monitored with miniature electronic temperature recorders and color-changing time/temperature indicator labels. RESULTS: The mean kinetic temperatures for the summer and winter periods were 25.1 degrees C (77.2 degrees F) and 12.7 degrees C (54.8 degrees F), respectively. In the summer, the electronic recorders logged temperatures exceeding 25 degrees C (59 degrees F) 37% of the time and more than 30 degrees C (86 degrees F) 6% of the time. In the winter, temperatures less than 15 degrees C (59 degrees F) were recorded 83% of the time. The mean kinetic temperatures obtained from the electronic recorder and the time/temperature indicator labels differed by less than 0.7 degree C (1.3 degrees F). The results show that medications on an air medical helicopter are subject to temperatures out of the recommended range and that time/temperature indicator labels can reliably monitor mean kinetic temperatures. 相似文献
56.
57.
目的 提出空气净化器对甲醛净化效果评价的时间和测定间隔。方法 在 30m3和 1 5m3测试舱中进行自然衰减试验和甲醛去除效果试验。结果 自然衰减测试时间为 2 5小时 ,测定间隔为 15分钟 ;总衰减测试时间为 1 2小时 ,测定间隔为 5分钟。当空气净化器风量 <30m3 h或评价无风量空气净化产品时 ,可在 1 5m3测试舱中进行评价 ,自然衰减和总衰减的测试时间均为 6 4min ,测定间隔为 8分钟。结论 不同类型空气净化器对甲醛净化效果评价的测定时间和测定间隔不同 相似文献
58.
上海市部分空调系统微生物污染状况的初步调查 总被引:15,自引:0,他引:15
[目的]了解当前上海地区空调系统微生物污染情况,更好地控制空调环境的卫生状况。[方法]采用多阶段随机抽样方法,对上海市不同类型空调系统进行横断面调查。选取上海市闵行、闸北、浦东、静安、黄浦、长宁6个区中央及非中央两种类型的空调系统,对其过滤网、热交换器、空调冷却循环水中的细菌总数、霉菌总数以及军团菌、溶血性链球菌、金黄色葡萄球菌、芽胞杆菌等项目进行检测。[结果]中央空调冷却循环水在6月~9月份军团菌污染阳性率均在50%以上,10月份呈现明显下降趋势;在各种不同类型的公共场所中,地铁站、医院、商场酒店的军团菌阳性率均在55%以上;不同类型空调系统过滤网、热交换器的细菌总数、霉菌总数及军团菌、溶血性链球菌、金黄色葡萄球菌检出率均较低,而芽胞杆菌检出率高。[结论]上海市中央空调冷却水军团菌污染状况严重,而不同类型空调系统过滤网、热交换器的卫生状况相对较好。 相似文献
59.
[目的 ]评价地铁车站内站台和站厅挥发性有机物 (VOCs)的污染水平 ,并判断来源。 [方法 ]用气相色谱质谱联用仪对地铁车站站台和站厅挥发性有机物浓度进行测定 ,并用挥发性有机物富集指数 (VEF)进行分析。 [结果 ]两车站站台和站厅监测点白天及夜晚的CO2 浓度差异存在显著性 (P <0 .0 1) ,监测点白天和夜晚的VOCs浓度差异无显著性 (P >0 .0 5 )。地铁车站内VOCs的主要来源来自其自身室内排放源 ,室外污染物浓度及通风状况等可能对室内VOCs有影响。 [结论 ]地铁车站内存在VOCs污染 ,用VEF评价地铁车站内VOCs污染状况 ,能较简便、准确地反映其污染物来源 ,并可比较不同车站之间VOCs的浓度水平 相似文献
60.
上海市某区居民脑卒中死亡与大气污染关系的时间序列研究 总被引:4,自引:0,他引:4
目的 分析大气污染急性暴露对居民每日脑卒中死亡的影响。方法 采用时间序列的半参数广义相加模型 ,在控制死亡的长期趋势、气象因素、“星期几效应”等混杂因素的基础上 ,分析了上海市某区 2 0 0 1年 1月 1日~ 12月 31日大气污染与居民每日脑卒中死亡的关系。结果 大气PM10 ,SO2 和NO2 4 8h平均浓度每增加 10 μg m3 ,居民因脑卒中而死亡的相对危险度分别为 1 0 0 8(95 %CI 1 0 0 0~ 1 0 16 ) ,1 0 17(95 %CI 0 998~ 1 0 36 )和 1 0 2 9(95 %CI1 0 0 1~ 1 0 5 7)。结论 上海市某区目前的PM10 和NO2 水平对居民脑卒中死亡有影响。 相似文献