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121.
Screening of potential MRSA-positive patients at hospital admission is recommended in German and international guidelines. This policy has been shown to be effective in reducing the frequency of nosocomial MRSA transmissions in the event of an outbreak, but the influence of screening on reducing hospital-acquired MRSA infections in a hospital setting where MRSA is endemic is not yet well-documented. This study describes the effect of hospital-wide screening of defined risk groups in a 700-bed acute care hospital during a period of 19 months. In a cohort study with a 19-month control period, the frequencies of hospital-acquired MRSA infections were compared with and without screening. In the control period, there were 119 MRSA-positive patients, of whom 48 had a hospital-acquired MRSA infection. On the basis of this frequency, a predicted total of 73.2 hospital-acquired MRSA infections was calculated for the screening period, but only 52% of the expected number (38 hospital-acquired MRSA infections) were observed, i.e., 48% of the predicted number of hospital-acquired MRSA infections were prevented by the screening programme. The screening programme was performed with minimal effort and can therefore be recommended as an effective measure to help prevent hospital-acquired MRSA infections.  相似文献   
122.
The objective of this study was to assess the in vivo fate of poly(2-(dimethylamino)ethyl methacrylate) (pDMAEMA)-based polyplexes after intravenous administration into mice. Circulation kinetics and tissue distribution in terms of plasmid localization and transfection efficiency were assessed. To gain more insight into the observed biodistribution and gene expression profile, the interaction of pDMAEMA-based polyplexes with blood components (erythrocytes and albumin) was investigated in vitro. In the case of i.v. injection of positively charged polyplexes at a dose of 30 microg DNA most of the radioactivity was found in the lungs and the liver 60 min after injection. In the case of pDMAEMA/DNA polyplexes with a negative charge, uptake occurred mainly by the liver. Administration of positively charged complexes at a 30 microg DNA dose resulted in reporter gene expression primarily in the lungs. Injection of negatively charged complexes and naked plasmid did not result in luciferase expression in any of the organs examined. In vitro turbidity experiments showed the induction of a charge dependent aggregation process upon addition of albumin to the polyplexes pointing out to the involvement of aggregate formation in the dominant lung uptake of the positively charged polyplexes. Also, incubations of polyplexes after pre-incubation with a physiological concentration of albumin with washed erythrocytes confirmed that polyplexes induce the formation of extremely large structures. This paper underlines the need for the design of systems with reduced interaction with blood components to promote the delivery of DNA to target tissues outside the lungs.  相似文献   
123.
肠易激综合征(IBS)是一组持续存在或反复发作的临床症候群,主要症状有腹痛、腹胀、排便习惯改变和大便性状异常、黏液便等,经检查排除可引起这些症状的器质性疾病。临床分为肝木乘脾型腹泻、脾胃虚弱型腹泻、脾肾阳虚型腹泻、肝郁脾虚型便秘四型,根据临床辨证分别施以不同治法,不同方药治疗,有显著疗效。同时,教育患者平时养成良好的饮食卫生习惯,不饮生水,不食生冷瓜果,忌食辛辣、油腻、肥厚之品,保持心情舒畅,怡情悦志,注意保暖,可加强疗效,防止复发。  相似文献   
124.
There is limited information on the relationship between parental practices that specifically discourage current cigarette smoking and adolescent cessation, and how this relationship varies by age. Among 1629 adolescent smokers, self-reported receipt of parental communication not to smoke was significantly and positively associated with readiness to quit. The strength and significance of this association decreased from early to middle adolescence and was not significant in late adolescence.  相似文献   
125.
Objective Changes in serum albumin may reflect systemic immunoinflammation and hypermetabolism in response to insults such as trauma and sepsis. Esophagectomy is associated with a major metabolic stress, and the aim of this study was to determine if the absolute albumin level on the first postoperative day was of value in predicting in-hospital complications. Methods A retrospective study of 200 patients undergoing esophagectomy for malignant disease at St. James Hospital between 1999 and 2005 was performed. Patients who had pre and postoperative (days 1, 3, and 7) serum albumin levels measured were included in the study. Patients were subdivided into three postoperative albumin categories <20 g/l, 20–25 g/l, >25 g/l. Logistic regression analysis was performed to calculate the odds of morbidity and mortality according to the day 1 albumin level. Results Patients with an albumin of less than 20 g/l on the first postoperative day were twice as likely to develop postoperative complications than those with an albumin of greater than 20 g/l (54 vs 28% respectively, p < 0.011). Correspondingly, these patients also had a significantly higher rate of Adult Respiratory Distress Syndrome (22 vs 5%, p < 0.001), respiratory failure (27 vs 8%, p < 0.01) and in-hospital mortality (27 vs 6% (p < 0.001). On multivariate logistic regression analysis, day 1 albumin level was independently related to postoperative complications (odds ratios, 0.89: 95%; confidence intervals, 0.83–0.96; p < 0.005). In addition, albumin <20 g/l on the first postoperative day was associated with the need for further surgery and a return to ICU. Conclusion Serum albumin concentration on the first postoperative day is a better predictor of surgical outcome than many other preoperative risk factors. It is a low cost test that may be used as a prognostic tool to detect the risk of adverse surgical outcomes.  相似文献   
126.
军队在职干部腰身指数与心血管危险因素相关性探讨   总被引:1,自引:1,他引:0  
目的 研究用腰身指数(腰围/身高比值WHtR)作为腹型肥胖指标探讨与心血管危险因素的相关性。方法 对2005年3月~2006年12月入住广州疗养院的军队在职干部共495人进行身高、体重、腰围、血压、心率、生化等检测,并进行统计学分析。结果 腰身指数异常组的年龄、体重、SBP、DBP、FBS、TC、TG以及尿酸均显著高于腰身指数正常组,HDL-C的结果则相反(P〈0.01~P〈0.001);同时腰身指数与年龄、体重、SBP、DBP、FBS、TC、TG呈显著正相关,与HDL-C呈显著负相关(P〈0.05~P〈0.001)。结论 腰身指数可作为有效的腹型肥胖参考指标,腰身指数异常者其心血管危险因素水平比正常者高,及时控制腰身指数可以有效改善人群的健康状况。  相似文献   
127.
Biostatisticians have frequently uncritically accepted the measurements provided by their medical colleagues engaged in clinical research. Such measures often involve considerable loss of information. Particularly, unfortunate is the widespread use of the so‐called ‘responder analysis’, which may involve not only a loss of information through dichotomization, but also extravagant and unjustified causal inference regarding individual treatment effects at the patient level, and, increasingly, the use of the so‐called number needed to treat scale of measurement. Other problems involve inefficient use of baseline measurements, the use of covariates measured after the start of treatment, the interpretation of titrations and composite response measures. Many of these bad practices are becoming enshrined in the regulatory guidance to the pharmaceutical industry. We consider the losses involved in inappropriate measures and suggest that statisticians should pay more attention to this aspect of their work. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
128.
英语阅读障碍儿童词汇命名加工特征的研究   总被引:1,自引:1,他引:0  
目的研究英语阅读障碍儿童操作英语词汇的相关能力 ,探索英语阅读障碍的表现特点与矫治的手段。方法英语真、假词命名实验 ,观察 3 4名阅读障碍儿童和 3 4名对照组儿童的实验结果。结果 ( 1)障碍组右视野在真、假词的命名时间上与对照组存在显著差异 ;( 2 )障碍组在真词和假词上的命名错误率均大于正常组 ,假词命名的错误率大幅增加。 ( 3 )障碍组右视野的真词命名时间明显长于左视野 ,假词命名的错误率也明显大于左视野。结论英语阅读障碍的儿童显示出了操作英语语音能力的欠缺以及左测大脑半球活动水平不足的倾向。  相似文献   
129.
文中基于免疫系统有关免疫活性细胞或分子与外来抗原相互作用的非线性的动力学模型对中医学正邪相争理论及其扶正祛邪治则进行了新的诠释,提出了新的研究思路。认为:中医学关于外感邪气致病的六经、卫气营血和三焦辨证在本质上是识别抗原与免疫活性细胞或分子相互作用的三种不同的非线性动力学诊断模式,其证相应于这一过程中不同的非线性动力状态,可以用一个或一组非线性动力学方程进行定量描述。一个证常常对应于抗原与免疫活性的细胞或分子非线性动力学相互作用相空间中的一个稳定或不稳定的极限环和混沌,这可以作为证诊断的图形或形象标识。以中医学扶正祛邪的治疗思想为先导,有可能研制出全新靶向的和更有效的治疗传染性疾病的药物。  相似文献   
130.
腹腔镜胆囊切除术转开腹可能性评分系统建立和运用   总被引:27,自引:0,他引:27  
目的 根据术前临床资料建立预测腹腔镜胆囊切除术转开腹可能性的评分系统。方法 对邵逸夫医院 1994年 4月 4日至 2 0 0 1年 6月 30日的 7134例LC的术前临床资料进行单因素分析 ,筛选出中转开腹的危险因素 ,再进行logistic多元回归分析。男性、高龄 (≥ 6 5岁 )、上腹部手术史、糖尿病、总胆红素升高 (≥ 1 2mg/dl)、胆囊壁增厚 (≥ 4cm )、胆总管直径增宽 (≥ 8cm)、急性胆囊炎是转开腹的危险因素并被分别赋值 ,建立预测转开腹可能性的评分系统。计算 7134例LC的综合得分 ,比较不同得分组转开腹率。用ROC曲线评价该评分系统的效能。 2 0 0 1年 7月 1日至 2 0 0 1年 12月 31日 938例LC运用该评分系统 ,比较各得分组转开腹率的差异。结果  7134例LC中各组得分越高 ,转开腹率越高 ,且多数相邻两组的转开腹率有显著性差异 (P <0 0 1)。ROC曲线以下面积为0 81,标准误为 0 0 1。 938例LC中的各组也是得分越高 ,转开腹率越高 ,且多数相邻两组的转开腹率有显著性差异 (P <0 0 5 )。结论 根据危险因素预测LC转开腹可能性 ,以指导临床工作。  相似文献   
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