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21.
中国饮用水源水中藻类卫生标准的研究   总被引:17,自引:0,他引:17  
施玮  蒋颂辉  朱惠刚 《卫生研究》2003,32(2):97-100
为制定饮用水源中藻类限值 ,结合国内外文献调查研究毒理学试验和现场生态学调查资料 ,根据世界卫生组织 (WHO)和卫生部推荐的饮用水中微囊藻毒素MC -LR的限值、藻类生物量和MC -LR浓度关系以及毒理学实验所得到的藻类的无作用浓度而制定饮用水源中藻类限值。结果显示 ,推荐饮用水源中藻类三级限值分别为 :安全限值 :1.0× 10 4个 升 ;警戒限值 :2 .1× 10 5个 升 ;危险限值 :1.2× 10 6 个 升。提示饮用水源中藻类限值在日常工作中有显著意义和可行性  相似文献   
22.
重庆地区驾驶员血液中乙醇浓度与驾驶能力的关系   总被引:5,自引:0,他引:5  
目的 探讨重庆地区驾驶员血液中乙醇浓度 (BAC)和驾驶能力的关系 ,为交通安全立法提供科学依据。 方法 随机选择重庆地区 59名驾驶员志愿者 ,建立饮酒后驾车模型、科学的BAC测定以及驾驶能力评价体系 ,对不同BAC下驾驶能力进行测评。 结果 受试者出现驾驶能力损害时的BAC均数为 685.9mg/L ,最小值 190 .0mg/L ,最大值 152 0 .0mg/L ,总体均数 95%可信区间为 60 2 .4~ 70 9.5mg/L。汉族和土家族间、汉族男性和女性间、2 3~ 3 5岁和 3 6~ 56岁年龄组间差异无显著性意义 (P >0 .0 5) ,而既往饮酒量不同的三个组别间差异有显著性意义 (P <0 .0 5)。随着BAC增高 ,驾驶能力受损人数增加。在 2 0 0 .0mg/L有 3 % (2 / 59)的受试者驾驶能力降低 ,80 0 .0mg/L则达到 68% (40 / 59)。 结论 随着BAC增高 ,重庆地区驾驶员驾驶能力受损人数比例增加 ,出现驾驶能力明显损害时BAC为 60 2 .4~ 70 9.5mg/L ,既往酒量较大人群中该值较高  相似文献   
23.
为了寻找能够控制硝普钠释放的控释膜,研究了数种高分子膜的通透性,其中以经过热处理的聚乙烯醇(PVA)膜控制硝普钠释放性能较好。进一步研究了热处理条件对PVA膜通透性的影响,发现只要热处理的温度和时间恰当,就可以获得具有一定通透性的PVA膜。  相似文献   
24.
25.
BACKGROUND: It has been proposed that alcohol consumption may be one of the lifestyle factors associated with a westernized, urban, and affluent lifestyle contributing to the rise in atopic disease. OBJECTIVE: The aim was to investigate the association between alcohol consumption and atopy (aeroallergen sensitization). METHODS: In 1982, a population-based cross-sectional study of 3608 Danes (79% of the invited), aged 30, 40, 50, and 60 years, was carried out. Information on alcohol consumption was obtained by a questionnaire. Aeroallergen sensitization was defined as a positive test for the detection of specific IgE against a panel of 19 common inhalant allergens in stored serum samples. A total of 3317 subjects with complete information on all variables were included in the analyses. RESULTS: We found a statistically significant association between alcohol consumption and aeroallergen sensitization (independent of the type of alcoholic drink consumed). This association appeared to relate only to those who consumed more than 8 drinks/week. After adjustment for confounders this association was only statistically significant for those who consumed 15-21 drinks/week (adjusted odds ratio 1.8, 95% confidence interval 1.2-2.8). CONCLUSION: In this adult general population, self-reported alcohol consumption was positively associated with aeroallergen sensitization.  相似文献   
26.
Summary A pathologic study was undertaken of seven encephalic arteriovenous malformations, including five resected from one to seven days after balloon embolization, one resected 10 days after embolization with polyvinyl alcohol foam (PVA), and a large mesencephalic AVM in a patient who died eight weeks after a series of embolization procedures with PVA and silicone spheres. AVM's resected 6–7 days following balloon embolization showed focal mural and adventitial inflammatory infiltrates and parenchymal (i.e. non-vascular) necrosis of a large portion of one AVM. The AVM examined 7 days post-balloon embolization showed an intraluminal thrombus containing refractile particles surrounded by foreign body giant cells (FBGC's). The AVM removed 10 days after PVA embolotherapy showed mural and perivascular necrosis with infiltration by polymorphonuclear leukocytes. The single autopsy case showed FBGC's surrounding residual PVA, refractile particles deep within vascular walls, and marked mural thickening of AVM channel walls, changes that may represent a response to previous angionecrosis and inflammation at the time of embolization. These findings, the pathogenesis of which is discussed in detail, may help to explain some of the rare complications of iatrogenic embolotherapy with these materials, as well as providing evidence for the basis of their efficacy.Presented in part at the 63rd Annual meeting of the American Association of Neuropathologists, Seattle, Washington, June, 1987  相似文献   
27.
夜来香正丁醇提取物镇痛作用的研究   总被引:3,自引:2,他引:1  
目的:探讨夜来香正丁醇提取物对小鼠的镇痛作用。方法:采用醋酸扭体法、热板致痛法、电刺激致痛法研究夜来香正丁醇提取物对小鼠镇痛作用的影响。结果:夜来香正丁醇提取物对醋酸诱发小鼠扭体反应,热板致痛、电刺激致痛诱发的疼痛有显著的镇痛作用,且呈剂量依赖性。但纳洛酮不能对抗其镇痛作用。结论:夜来香正丁醇提取物有明显的镇痛作用。  相似文献   
28.
The daily fluid intake of male Wistar rats with simultaneous access to 6% ethanol and water was determined during a baseline period (1 week), following adrenalectomy (1 week) and for 3 weeks following SC implantation of hormone pellets containing corticosterone (CORT) or dexamethasone (DEX). Ethanol consumption dropped during the first week of adrenalectomy (ADX) but increased again in the absence of hormone replacement to reach preoperative levels during the ensuing weeks. The CORT treatment, which produced plasma hormone levels similar to the 24-h mean concentration of adrenally intact rats, not only reversed the effect of ADX on alcohol consumption but also enhanced it to levels above those observed in intact rats. Water intake was not affected by the CORT treatment. DEX implants stimulated water intake, but did not enhance the drinking of ethanol. SC injections of RU 28318 (type I corticosterone receptor antagonist; 10 mg/kg) or mifepristone (RU 38486; type II receptor antagonist; 25 mg/kg) at the beginning and halfway through three daily, 6-h tests failed to affect ethanol drinking in adrenally intact rats or in ADX rats bearing CORT implants. Similarly, there was no effect of giving the two antagonists in combination. These results suggest that exogenous CORT can induce excessive alcohol intake in genetically unselected rats and that this facilitatory effect may be mediated by non-genomic cellular mechanisms.  相似文献   
29.
Abstract. Medical and social problems related to alcohol use are frequently seen in the ED. Often, the tempo of emergency medicine practice seems to preclude assessment beyond that required by the acute complaint. However, detection of ED patients with alcohol problems can occur using brief screening tools. This article was developed by members of the SAEM Substance Abuse Task Force, and describes screening tools that have been used successfully to identify atrisk and dependent drinkers. Their brevity, reproducibility, and accuracy vary somewhat, but screening can be realistically performed in the busy ED setting. The early detection of patients with alcohol problems would provide the opportunity for early intervention, and may reduce subsequent morbidity and mortality in this patient population.  相似文献   
30.
The effect of heavy drinking and sauna bathing on cardiac rhythm, blood pressure, and serum electrolyte and cortisol concentrations was studied in 10 healthy male volunteers. Sauna bathing induced a comparable, significant increase in heart rate with and without alcohol consumption. During sauna bathing without alcohol, systolic blood pressure remained at the baseline level, whereas sauna and alcohol together decreased systolic blood pressure markedly from 136 +/- 4 to 113 +/- 3 mmHg (P less than 0.01). Neither sauna alone, nor sauna combined with alcohol intake, increased the frequency of premature ventricular complexes. Serum potassium, calcium and cortisol concentrations changed slightly during sauna, but alcohol consumption did not contribute further to this. In conclusion, sauna bathing, even in combination with heavy drinking, does not appear to provoke cardiac arrhythmias in healthy young men. However, the risk of hypotension is increased when sauna bathing is combined with alcohol consumption.  相似文献   
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