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排序方式: 共有811条查询结果,搜索用时 233 毫秒
1.
活性氧自由基在生物体内参与生理,病理过程并起重大作用,在筛选和评价抗氧化药物时,越来越需要一种快速,简便,价廉而又可靠的抗氧化活性测定方法,本文发展了一种具备了上述优点新方法,SOD(超氧化物歧化酶)及其模拟物的工作已有很多,很多文献报道了其活性一;Cu(Ⅱ)。本文着重研究了另一个金属辅基,Zn^2+并且发现了Zn^2+独特的,但为人们忽视了的;抗氧化活性加强作用。  相似文献   
2.
We computed skin-test sensitivity levels in 485 adults puncture-tested with eight standardized, high-quality inhalant allergens tested at single concentrations. In order to quantitate the "average" IgE-mediated skin sensitivity of each subject, we used both nonparametric and parametric statistical methods to generate two "allergy indices" (Allergy Index I and Allergy Index II) based on sensitivity end-point data from the subpopulations of individuals positive to six of the eight allergens. For the 192 skin test-positive subjects, Allergy Index I and Allergy Index II were significantly correlated with each other (rs = 0.98, p less than 0.001) and with the number of positive skin-test reactions (rs congruent to 0.9, p less than 0.001) as well as with log[total serum IgE] (r congruent to 0.4, p less than 0.01). In 102 ragweed-positive subjects, log[specific IgE to ragweed] was significantly correlated with ragweed-specific "ragweed indices I and II" (r congruent to 0.6, p less than 0.01). Furthermore, the average daily symptom scores reported by 14 ragweed-positive subjects during the ragweed pollination season were significantly correlated with ragweed indices I and II (p less than 0.05). We propose the use of Allergy Index II in epidemiologic and genetic studies of allergic phenotypes as well as in clinical decisions for diagnosis and immunotherapeutic intervention.  相似文献   
3.
外伤性颌骨骨折的临床诊治分析   总被引:2,自引:0,他引:2  
目的:探讨骨折愈合影响因素。方法:对358例颌骨骨折病例,根据致伤原因、骨折部位及类型,治疗效果及随访结果进行总结。结果:治疗有效率95.87%。手术切开复位骨间固定265例,手法或牵引复位外固定93例;术后感染骨延迟愈合8例;合并口腔颌面部软组织损伤210例。结论:准确诊断,及时复位、固定,选择正确固定方式,防止感染,待别是应用坚固内固定技术能有效提高颌骨骨折治愈率。  相似文献   
4.
放化联合治疗老年非小细胞肺癌的可行性   总被引:8,自引:1,他引:8       下载免费PDF全文
 目的 评价老年非小细胞肺癌的单纯放疗及放疗化疗综合治疗的疗效及毒副作用 ,探讨其治疗可行性。方法  89例老年中晚期非小细胞肺癌患者 ,其中单纯放疗组 4 3例 ,放疗 +化疗综合治疗组 4 6例 ,比较两组的疗效和毒副作用。结果 单纯放疗组和放化综合治疗组的局部有效率、1年及 2年生存率分别为 6 9.77%、4 1 .86 %、1 7.1 4 %和 76 .0 9%、4 7.83%、2 1 .2 1 % ,经统计学处理 ,P >0 .0 5。两组毒副作用有显著的差异 ,综合治疗组胃肠道反应、骨髓抑制均比单放组明显。结论 老年中晚期非小细胞肺癌治疗十分复杂 ,应根据患者个体情况来选择治疗方案  相似文献   
5.
中药材肉桂的X衍射Fourier谱分析   总被引:3,自引:1,他引:3  
为鉴别中药材肉桂与川桂、少花桂和其伪品三钻风,本文应用粉末X射线衍射分析技术测定了10个样品的Fourier(付里叶)图谱。分析结果表明10个样品各自具有表现其所含化学成分总体特征的衍射图谱。并构成衍射模糊图形(定性)与特征标记峰(定量)的图谱特征。根据这些特征达到在衍射空间鉴别中药材的目的。  相似文献   
6.
7.
目的:探讨电磁场促进骨折愈合的研究进展。方法:阅读、研究国内外有关文献并进行综述。结果与结论:从实验研究、临床应用及作用机理3方面证实电磁场对骨折愈合有促进作用。  相似文献   
8.
Abstract

Although Lithuania has comprehensive health and safety legislation in line with EU requirements, on a range of general health and occupational health and safety (OHS) indicators, it is a poor performer. Survey data suggest that the norm for work in Lithuania is based on a regime of intensification without a participative working environment in which employees have a voice in safety management. Although European-style legislative reforms appear to be having no measurable effects on CHS performance in post-communist New Member States, the EU OHS strategy for 2007–2012 fails to take account of the deteriorated working environments in these states, suggesting that prospects for harmonization of working environment standards in the enlarged Europe may recede with eastward expansion.  相似文献   
9.
Unlike in most of the world, HIV incidence in the former Soviet Union continues to rise. While international labor migration has been identified as a potentially important contributor to this trend, most attention has been focused on risks of male migrants themselves. This study uses recent household survey data to examine HIV-related perceptions and actions of migrants’ left-behind wives in Armenia. Multivariate logistic regression analyses show that migrants’ wives are significantly more likely to suspect their husbands of extramarital sex than are non-migrants’ wives. The analyses detect greater worries about HIV infection and a higher likelihood of spousal communication on HIV matters among migrants’ wives, compared to non-migrants’ wives, but these differences are largely explained by the suspicion of husband’s extramarital sex. Finally, no difference between the two categories of women in the probability of consistent condom use with husbands is found. These findings are interpreted within the context of patriarchal culture and unequal gender relations in Armenian society as they are further reinforced by male migration. Implications of these findings for policies to increase women’s awareness of HIV risks associated with migration and their ability to reduce those risks are discussed.  相似文献   
10.
We estimate potential risks to human health in the UK from dietary exposure to lead from wild gamebirds killed by shooting. The main source of exposure to lead in Europe is now dietary. We used data on lead concentrations in UK gamebirds, from which gunshot had been removed following cooking to simulate human exposure to lead. We used UK food consumption and lead concentration data to evaluate the number of gamebird meals consumed weekly that would be expected, based upon published studies, to result in changes, over and above those resulting from exposure to lead in the base diet, in intelligence quotient (IQ), Systolic Blood Pressure and chronic kidney disease (CKD) considered in a recent opinion of the European Food Safety Authority (EFSA) to be significant at a population level and also in SAT test scores and in rates of spontaneous abortion. We found the consumption of <1 meal of game a week may be associated with a one point reduction in IQ in children and 1.2–6.5 gamebird meals per week may be associated with the other effects. These results should help to inform the development of appropriate responses to the risks from ingesting lead from ammunition in game in the UK and European Union (EU).  相似文献   
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