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1.
4132名少年儿童血压状况调查分析 总被引:5,自引:0,他引:5
目的了解7~14岁少年儿童血压特点,为流行病学及预防成人高血压提供参考数据。方法用统一标准采集血压及有关数据,用概率单位法行正态性检验,确定血压95%参考值范围,对年龄与血压和体质指数进行相关性分析,行U检验、t检验。结果随年龄增大血压也逐渐上升,各年龄段男女之间血压差异无统计学意义。体质指数随年龄增大而增加。血压偏高者其体质指数高于同年龄段中值水平。结论年龄与血压和体质指数呈正相关。血压偏高者体质指数都具有较高中值水平。 相似文献
2.
Potentially dangerous antibiotic resistant contaminants have permanently penetrated at least well-off western populations. The danger is so evident that some hospitals have started to refuse accepting patients who carry such bacteria. Sampling and enrichment measures in hygiene monitoring must be updated as they are corner stones in handling the problems and safeguarding the health care units. Their patients, when exposed to microorganisms are strenuous to treat. Sometimes even this fails, if the infections are spreading in weakened patients. The present review summarizes currently used technologies and the abilities of bacteria to avoid detection. Improved protocols on environmental monitoring in healthcare units are required. They should be comparable with contamination control in industries. Actually these measures in health care should be even stricter because human lives are directly endangered as the resistance of especially elderly patients is low. 相似文献
3.
人群归因危险度百分比 (populationattributableriskproportion ,PARP)是总体人群中某种疾病归因于某种因素的暴露所引起的发病 (死亡 )占全部发病 (死亡 )的百分比 ,反映该因素所引起的发病 (死亡 )占全部发病 (死亡 )的比重。通过PARP可了解各危险因素对人群中某疾病的发病所产生的影响 ,亦即消除某危险因素后 ,所产生的对预防该疾病的效果将占有多大比重。它能够为卫生政策的制订提供依据 ,有着重要的公共卫生的实际意义。目前常用的估计PARP的方法有两种 :一种是利用全国人群抽样调查获得的人群总暴露率来估计 ;另一种是利用某地区… 相似文献
4.
I-Chan Huang Richard J. Willke Mark J. Atkinson William R. Lenderking Constantine Frangakis Albert W. Wu 《Quality of life research》2007,16(6):1065-1072
Background Most US studies that estimate EQ-5D index score generally apply the UK preference weights. We compared the validity of a
newly-developed US weights to the UK weights for use of EQ-5D as a measure of health-related quality of life. Methods Data were collected from a randomized clinical trial for patients with HIV (n = 1,126) in the US. Convergent validity was examined by comparing Pearson correlations of EQ-5D index scores with the MOS-HIV
Health Survey scale scores and Physical and Mental Health Summary (PHS, MHS) scores using the US and UK weights. Known-groups
validity of EQ-5D US versus UK index scores was compared using clinical variables (CD4+ cell count and HIV viral load), and
the MOS-HIV PHS and MHS. Score changes in the EQ-5D index from baseline to week 50 were examined using effect size (ES) estimates.
Results The mean EQ-5D index scores was slightly higher using US weights than UK weights (0.87 vs. 0.84, respectively). The correlation
coefficient for EQ-5D utilities using the US and UK weights was 0.98. The correlations of EQ-5D index scores with the MOS-HIV
scores were moderate and similar using the US and UK weights. The EQ-5D index scores discriminated equally well for both versions
between levels of CD4+ count, HIV viral load, and PHS and MHS scores (P < 0.05), suggesting equivalent known-groups validity. The changes in EQ-5D index scores from baseline to week 50 were similar
for both versions (ES: 0.21 vs. 0.22 for US and UK, respectively), suggesting equivalent responsiveness to score changes.
Conclusions EQ-5D index scores generated using UK and US preference weights showed equivalent psychometric properties. For assessing
treatment benefit in a single population, the use of either the UK or US weights as a measure of HRQOL will not change inferences.
However, for comparisons across US and UK populations, the choice between these two weights should be based on their relevance
to the study population. 相似文献
5.
天子岭垃圾填埋场利用活性污泥法处理生活垃圾渗滤水,BOD_5测定的取样量公式为:V_i=k_1·V_(?)/COD_(cr),通过确定k_i值以确定取样体积.并分析了影响取样量的几种因素. 相似文献
6.
D. Trainer P.R. Pehrsson D.B. Haytowitz J.M. Holden K.M. Phillips A.S. Rasor N.A. Conley 《Journal of food composition and analysis》2010,23(8):843-851
The National Food and Nutrient Analysis Program (NFNAP) was implemented in 1997 to update and improve the quality of food composition data maintained by the United States Department of Agriculture (USDA). NFNAP was designed to sample and analyze frequently consumed foods in the U.S. food supply using statistically rigorous sampling plans, established sample handling procedures, and qualified analytical laboratories. Methods for careful handling of food samples from acquisition to analysis were developed to ensure the integrity of the samples and subsequent generation of accurate nutrient values. The infrastructure of NFNAP, under which over 1500 foods have been sampled, mandates tested sample handling protocols for a wide variety of foods. The majority of these foods were categorized into several major areas: (1) frozen foods; (2) fresh produce and/or highly perishable foods requiring refrigeration; (3) fast foods and prepared foods; (4) shelf-stable foods; (5) specialized study and non-retail (point of production) foods; and (6) foods from remote areas (e.g. American Indian reservations). This paper describes the sample handling approaches, from the collection and receipt of the food items to the preparation of the analytical samples, with emphasis on the strategies developed for those foods. It provides a foundation for developing sample handling protocols of foods to be analyzed under NFNAP and for other researchers working on similar projects. 相似文献
7.
片剂含量均匀度计量检验新方案的研究 总被引:5,自引:0,他引:5
本文通过大量测试工作,查明10批国产小剂量片剂的含量分布,在此基础上提出了计量检验新方案。采用计算机模拟随机抽样的方法,通过计算绘制了USP XX,BP,JP和新方案在正态分布和10批实际分布下的OC曲线。结果表明,当用于测定生产规模的片剂批时,与国外片剂含量均匀度计数检验方案中统计特性最优的USP XX方案相比,新方案NEW能在化验工作量相近的前提下,作出更准确的判断;新方案SMA能在不降低判断准确性的前提下,减少化验工作虽约三分之一。新方案还可减免分析方法误差对判定结果的影响。 相似文献
8.
Michael H. Stone Michael E. Rush Harry Lipner 《Pflügers Archiv : European journal of physiology》1978,375(2):147-151
The hormonal levels of the gonadotropins, the weight of selected organs and of the triceps surae as well as body composition were determined in Sprague Dawley rats at 3 and 6 weeks after intensive training with or without a methandrostenelone (Dianabol) supplement (0.35 mg/kg/day). The controls were sedentary rats of similar age and weight at the start of the experiment. The dianabol treated rats in the sedentary and exercise groups had a depression of plasma LH levels. There were no differences in body weight, specific gravity, lean body weight, fat or % fat between the two trained groups. Dianabol had no apparent effect on the measured parameters other than a depression of LH. 相似文献
9.
保持形状特征的自适应轮廓点采样算法 总被引:3,自引:0,他引:3
郑国焱 《中国医学物理学杂志》1996,13(4):205-207
在三角形贴面表面重建中,选择轮廓线上哪些点作为重建点,一方面决定重建的质量,另一方面决定重建的速度。本文提出了一种保持形状特征的变分辨率轮廓点采样算法。首先,建立了本算法的数学模型,我们认为离弧对应的弦距离最大的点可作为一个形状特征点。其次,利用二叉树数据结构递归实现了该算法。本算法具有保持轮廓形状特征、根据形状复杂度自适应决定采样频率、编程简单等优点。 相似文献
10.
Nadine Gerin-Portier Jean Bourgeois Lucien Brasseur 《Pflügers Archiv : European journal of physiology》1970,314(4):263-273
Summary The differences inP
O
2readings between gas and blood were studied with a Clark-type electrode in the range of 38.5 to 713 mm HgP
O
2.The tonometered blood samples were taken in two different ways. The results showed that the gas-blood ratior
b(equilibrating gasP
O
2reading/equilibrated bloodP
O
2reading) depended not only on the sampling method but also on theP
O
2range: it varied from 1.005 to 1.032 for aP
O
2of 96.5 mm Hg, and from 1.040 to 1.081 for aP
O
2of 713 mm Hg according to the sampling procedure.A theoretical analysis demonstrated that the variation ofr
bwith the bloodP
O
2can be attributed to the influence of the degree of oxygen saturation of the hemoglobin on theP
O
2gradient existing in the blood diffusion boundary layer adhering to the electrode membrane.This work was supported by grants from the High Authority of the European Coal and Steel Community and from the Fonds de la Recherche Scientifique Médicale, Belgium. 相似文献