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991.
由苍蝇传播引起E.coli O157:H7感染爆发的评估模型的建立 总被引:1,自引:0,他引:1
目的 建立苍蝇对E.coli O157:H7传播作用的定量危险性评估模型。方法 在Excel工作表中模拟E.coli O157:H7的粪口传播过程,利用@RISK软件对模型进行Monte Carlo模拟。结果 由此交叉污染途径引起人群感染的概率为10^-5~10^-3/餐。模型预测的结果与爆发调查数据基本吻合。通过模型分析可知,苍蝇排泄物中的含菌量及苍蝇的数量是影响人群感染危险性的重要因素。结论 以苍蝇污染途径模拟E.coli O157:H7感染危险性的定量评估模型,该模型是一个非常有用的评估危害与危险性关系的评估工具。 相似文献
992.
目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用. 相似文献
993.
早产是围产保健工作面临的一项严重临床问题,根据世界卫生组织的定义,早产是指从孕妇末次月经周期首日算起,孕龄《37周或259天的分娩. 相似文献
994.
The derivation of safe levels of exposure in humans for compounds that are assumed to cause threshold toxicity has relied on the application of a 100-fold uncertainty factor to a measure for the threshold, such as the no observed adverse effect level (NOAEL) or the benchmark dose (BMD). This 100-fold safety factor consists of the product of two 10-fold factors allowing for human variability and interspecies differences. The International Programme on Chemical Safety has suggested the subdivision of these 10-fold factors to allow for variability in toxicokinetics and toxicodynamics. This subdivision allows the replacement of the default uncertainty factors with a chemical-specific adjustment factor (CSAF) when suitable data are available. This short review describes potential options to refine safety factors used in risk assessment, with particular emphasis on pathway-related uncertainty factors associated with variability in kinetics. These pathway-related factors were derived from a database that quantified interspecies differences and human variability in phase I metabolism, phase II metabolism, and renal excretion. This approach allows metabolism and pharmacokinetic data in healthy adults and subgroups of the population to be incorporated in the risk-assessment process and constitutes an intermediate approach between simple default factors and chemical-specific adjustment factors. 相似文献
995.
Miller TW Clayton R Miller JM Bilyeu J Hunter J Kraus RF 《Child psychiatry and human development》2000,30(4):255-272
School violence in rural communities has gained considerable attention nationally. Examined are theoretical considerations involving escape theory, the risk and protective factors for school violence, case analyses of recent case studies, and discussion of recent school violence involving fatal injuries to others. Also discussed are diagnostic issues in understanding children who are at-risk for school violence and ways school violence maybe managed in the schools. Suggestions and recommendations including recommendations provided by the National School Safety Center for school personnel are offered, as are steps to be taken in creating a safe school environment. This information may be helpful to child psychiatry and clinical personnel who provide services to school aged children. 相似文献
996.
Eberhart LH Högel J Seeling W Staack AM Geldner G Georgieff M 《Acta anaesthesiologica Scandinavica》2000,44(4):480-488
BACKGROUND: So far there are three different scores to predict postoperative vomiting (PV: Apfel et al., 1998) or postoperative nausea and vomiting (PONV: Koivuranta et al., 1997; Palazzo and Evans, 1993). All three scores used logistic regression analysis to identify and create weights for the risk factors for PV or PONV. In short, these were sex, age, history of previous PONV, motion sickness, duration of anaesthesia, and use of postoperative opioids. However, an external evaluation and a comparison of these scores has not been performed so far. METHODS: Patients undergoing a variety of surgical procedures under general anaesthesia were studied prospectively. Preoperatively, they completed a questionnaire concerning potential risk factors for the occurrence of PV or PONV implemented in the three risk scores. Balanced anaesthesia (induction agent, nondepolarising neuromuscular blocker, opioid, and inhalation agent in nitrous oxide/oxygen) was performed. No intravenous anaesthesia or any antiemetic prophylaxis was applied. Postoperatively, the patients were observed in the recovery room for the occurrence of PV and PONV and were visited twice on the ward within the 24-h observation period. Both the patients and the nursing staff were asked whether PV or PONV was present. The severity of PONV was categorised using a standardised scoring algorithm. A total of 1,444 patients was finally included into the analysis. Using information of the predicted risk for the individual patients and the actual occurrence of PV or PONV, Receiver Operator Characteristics (ROC-curves) were drawn. The area under each ROC-curve was calculated as a means of the predictive properties of each score and was compared for statistical differences. RESULTS: For prediction of PONV (any severity) the AUC-values (AUC=area under the curve) and the corresponding 95%-confidence intervals were: Apfel: 0.70 (0.67-0.72); Koivuranta: 0.71 (0.69-0.73); Palazzo: 0.68 (0.65-0.70). For prediction of PV: Apfel: 0.73 (0.71-0.75); Koivuranta: 0.73 (0.70-0.75); Palazzo: 0.68 (0.65-0.70). Thus, all three scores appeared to have a moderate accuracy as measured by the AUC. The score of Koivuranta predicts PONV (P=0.007) and also PV (P=0.002) significantly better than Palazzo's score. Furthermore, for predicting of PV the score of Apfel was also superior to Palazzo's score (P=0.005). All three scores predict PV with the same accuracy as PONV. CONCLUSION: The occurrence of PV and PONV in patients undergoing surgery under balanced anaesthesia can be predicted with moderate but acceptable accuracy using one of the available risk scores, regardless of local surgical or anaesthesiological circumstances. For clinical practice, we recommend the score published by Koivuranta, since its calculation is very simple. 相似文献
997.
Xu Q Wang YH Tong WJ Gu ML Wu G Buren B Liu YY Wang J Li YS Feng H Bai SL Pang HH Huang GR Fang MW Zhang YH Wu ZL Qiu CC 《Biomedical and environmental sciences : BES》2004,17(2):177-186
Objective To investigate the association of specific functional gene ACE (I/D) variants of the renin-angiotensin system with essential hypertension (EH) and interaction between ACE (I/D) gene and risk factors for EH in a genetically homogenous Mongolia rural population of China. Methods Individuals (n=1099) were recruited from general population of Kezuohouqi Banner in Inner Mongolian Autonomous Region. Results The association was found between ACE genotype DD plus ID and EH, with an interaction between ACE genotype DD plus ID and cigarette smoking in an additive model. Cigarette smoking index and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 7.10 to 1.16. Interaction between ACE genotype DD plus ID and alcohol drinking on EH appeared an additive model. Alcohol drinking index and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 1.66 to 1.09. BMI and ACE gene showed a low exposure-gene (LEG) effect on EH, with interaction indices from 6.15 to 2.49.Interactions between ACE genotype and WHR on EH showed a multiplicative model. In a short, there was an interaction between ACE gene and cigarette smoking, alcohol drinking and BMI on EH,especially in a low dose-exposure effect.Cpmchusion It is important for individuals who carry ACE D allele gene to prevent FH, and furthermore, to prevent and control coronary heart disease, in a view of population-based prevention. 相似文献
998.
医疗保险风险因素的相对风险度分析 总被引:1,自引:0,他引:1
目的 :探讨医疗保险风险因素的相对风险度及其分析方法。方法 :借鉴流行病学研究方法 ,用 logistic回归模型产生比值比 (OR)来刻画风险因素与医疗保险赔付 (损失 )之间的定量关系。结果 :实例拟合单因素及多元 logistic回归模型 ,得到各风险因素的 OR值并能合理地解释。结论 :相对风险度分析为医疗保险风险控制提供了新的分析思路和定量依据 相似文献
999.
原发性肝癌发病主要危险因素的Meta分析 总被引:16,自引:0,他引:16
目的 :探讨中国人群肝癌发生的主要危险因素 ,为预防决策提供依据。方法 :利用 Meta分析方法综合国内 1987~ 2 0 0 2年关于肝癌发病危险因素的研究文献 15篇。累计病例 4 795例 ,对照 5 90 4例。结果 :各因素合并比值比分别为 :HBV感染 OR=8.90 (95 CI:7.19~ 11.0 0 ) ;乙肝病史 OR=10 .0 2 (95 CI4 .83~ 2 0 .78) ;抗 - HCV OR=4 .4 1(95 CI:2 .72~ 7.14 ) ;肝癌家族史 OR=3.17(95 CI:2 .4 3~ 4 .13) ;饮酒 OR=1.79(95 CI:1.35~ 2 .39) ;饮沟塘水 OR=1.77(95CI:1.30~ 2 .4 2 ) ;吸烟 OR=1.4 1(95 CI:1.0 5~ 1.89)。结论 :目前影响中国人群肝癌发生的主要因素为乙肝病史、HBV感染、遗传因素、丙型肝炎病毒感染等 相似文献
1000.
建筑工地工人艾滋病防治知识影响因素的调查 总被引:6,自引:2,他引:6
目的 :研究建筑工地工人艾滋病防治知识知晓程度 ,分析其影响因素。方法 :问卷调查 ,数据采用 Foxpro软件录入 ,用 SPSS8.0 for Windows软件进行单因素分析和 L ogistic回归分析。结果 :婚姻、性别、文化程度、宣传途径是影响建筑工地工人艾滋病防治知识知晓度的主要因素。结论 :对建筑工地工人开展艾滋病防治知识宣传应采取电视、报纸等形式 ,主要针对未婚男性 ,内容通俗易懂 ,以提高他们艾滋病防治知识的知晓度 相似文献