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991.
Relationships between air quality, a variety of environmental risk factors, and calf respiratory health were studied in 13 naturally ventilated calf barns during winter. A minimum of 12 preweaned calves were randomly selected and scored for the presence of respiratory disease in each barn. An air sampling device was used to determine airborne bacteria colony-forming units per cubic meter (cfu/m3) of air in calf pens and central alleys within the barns. Airborne bacteria samples were collected on sheep blood agar (BAP) and eosin methylene blue (EMB) agar plates. Temperature and relative humidity were recorded in each calf pen, the barn alley, and outside the barn. Samples of bedding were collected in each pen and DM was measured. Pen bedding type and a calf nesting score (degree to which the calves could nestle into the bedding) was assigned to each barn. Calf numbers, barn and pen dimensions, ridge, eave, and curtain openings, and exterior wind speed and direction were determined and used to estimate building ventilation rates. Factors that were significantly associated with a reduced prevalence of respiratory disease were reduced pen bacterial counts (log10 cfu/m3) on BAP, presence of a solid barrier between each calf pen, and increased ability to nest. Individual calf pen bacterial counts were significantly different from barn alley bacterial counts on both BAP and EMB. Significant factors associated with reduced calf pen bacterial counts on BAP were increasing pen area, increasing number of open planes of the calf pen, decreasing pen temperature, and wood-particle bedding. Significant factors associated with reduced alley bacterial counts on BAP were increased ventilation changes per hour, increased barn volume per kilogram of calf, reduced pen bacterial counts, and barn type. 相似文献
992.
纳米科技的发展使纳米在各个领域得到了广泛的应用。由于金纳米颗粒具有较高的摩尔吸光系数和特殊的光学、电学、磁学性质,因此它在化学、生物传感、疾病诊断和食品检测等领域的应用取得了突出进展。综述了最近几年金纳米颗粒在疾病诊断和食品检测领域的最新研究进展,特别介绍了国家纳米科学中心近期的研究结果,他们重点研发了可控功能化纳米材料的合成和应用,构建了便携式、高灵敏度的生物化学分析方法系列,为HIV和阿尔茨海默等重大疾病的诊断提供了新方法。讨论了金纳米颗粒具有的优势及存在的问题,并对其未来的发展进行了展望。 相似文献
993.
Alexander M. Crizzle Sherrilene Classen Michel Bédard Desiree Lanford Sandra Winter 《Accident; analysis and prevention》2012
Screening tools such as the MMSE have been used extensively in driving research studies to determine mild cognitive impairment or dementia. While some studies have shown the MMSE to correlate with driving performance, few studies have shown the predictive validity of the MMSE in determining on-road performance. In a sample of 168 community dwelling older adults, including 20 with Parkinson's disease (PD), the primary objective was to determine the validity of the MMSE to predict pass/fail outcomes of an on-road driving test using receiver operating characteristics curves. The area under the curve (AUC), an index of discriminability, for the total sample was .654, 95% CI = 0.536–0.772, p = .009. Meanwhile, the AUC for the PD group was 0.791, 95% CI = 0.587–0.996, p = .036. The total sample showed statistically significant yet poor predictive validity. However, the PD group showed statistically significant and good predictive validity of the MMSE to predict pass/fail outcomes on the road test, but caution is warranted as the confidence intervals are wide (due to small sample) and the positive and negative predictive values are less than desirable due to the associated error. The findings show that using the current cut-off point of ≤24 on the MMSE is not adequately sensitive to predict on-road performance in both community dwelling older drivers and in drivers with PD. This study offers strong evidence to support the current best practice of not using the MMSE in isolation to predict on-road performance. 相似文献
994.
Banu Mansuro?lu Zeynep Mustafaeva 《Materials science & engineering. C, Materials for biological applications》2012,32(2):112-118
Intermolecular complex by electrostatic interaction and specifically coupled conjugates between polyacrylic acid (PAA) and a synthetic peptide representing 170-188 sequence from the GH loop of VP1 protein of foot-and-mouth disease virus (FMDV) were investigated as an intermolecular model system due to their importance in biotechnology and immunology. In this study, polyacrylic acid (PAA) with a synthetic peptide representing 170-188 sequence from the GH loop of VP1 protein of foot-and-mouth disease virus at a wide range of mixing ratios of components (CPeptide/CPAA 0.1, 0.25, 0.5, 0.75 and 1.0, respectively) were characterized by size-exclusion high performance liquid chromatography with on-line refractive index, UV, light scattering and viscometer detectors. The results revealed that two molecules are both negatively charged as a result of repulsive forces preventing complex formation at neutral pH. Therefore, these molecules bound covalently to each other by using water-soluble carbodiimide when pH levels are higher than the pI of the peptide. High performance liquid chromatography analysis showed that the amount of protein-polymer complex increased and free peptide amount decreased with the increase in molar ratio of the peptide. Also, this paper presents that number of the bound peptide molecules with one PAA molecule was expressed by a Langmuir-type equation as a function of the amount of excess synthetic peptide existing free in the solution. 相似文献
995.
996.
Zapolski T Jaroszyński A Drelich-Zbroja A Furmaga J Wysokiński A Książek A Szczerbo-Trojanowska M Rudzki S 《Hemodialysis international. International Symposium on Home Hemodialysis》2012,16(2):220-232
This study was performed to investigate the relationship between left atrium (LA) volume index (LAVI) and left ventricle electrical activity presumably repolarization in end‐stage renal disease patients. Study group was consisted of 120 dialyzed patients divided into two subgroups: 57 (age 50.7 ± 7.1) were on continuous ambulatory peritoneal dialysis (CAPD) and 73 (age 51.6 ± 7.6) were hemodialyzed (HD). All patients were undergoing three‐dimensional vectorcardiographic (VCG) monitoring to assess parameters concerning T vector: QRS‐T angle, Tel, and Taz. Standard echocardiography was performed to assess: LAmax, LAshort, LAlong. LAVI was calculated due to formula: LAVI = (π/6X [LAmax × LAshort × LAlong])/m2. LAVI in HD as well as in CAPD patients was significantly higher compared with controls (respectively: 36.29 ± 10.92; 36.41 ± 11.06; 20.64 ± 6.77 mL/m2). The calculated cutoff value of LAVI was 36.32 mL/m2. In HD patients, the strong correlations between LAVI and QRS‐T angle and Tel were determined (respectively: r = 0.407, P < 0.001 and r = 0.359, P = 0.006). Similarly in CAPD group were significant associations between LAVI and QRS‐T angle and Tel (respectively: r = 0.423, P < 0.001 and r = 0.374, P = 0.004). The QRS‐T angle, Tel and Taz are independently and markedly associated with LAVI in both HD and CAPD patients. LAVI and VCG indices are higher in both HD and CAPD patients. Correlation between QRS‐T angle and LAVI may reflect unfavorable influence on the electrical activity of the heart in dialyzed patients with left ventricle diastolic dysfunction. LAVI cutoff value is useful biomarker for stratification of ventricle repolarization disturbances in those patients. 相似文献
997.
998.
目的:探讨64排多层螺旋CT冠状动脉成像的临床应用价值.方法:对230例临床拟诊为冠心病患者行64排多层螺旋CT血管成像,对所有原始数据进行冠状动脉三维重建等图像后处理,显示冠状动脉主干及主要分支,并对图像质量进行判定.结果:对比选择性冠状动脉造影检查显示64排多层螺旋CT冠状动脉成像对中度及以上狭窄的敏感性和特导性分别为92.5%和96.3%.结论:64排螺旋CT对中度及以上的冠脉狭窄具有良好的诊断价值,基本满足冠心病的诊断需求,可作为冠心病高危人群的一种初筛手段,具有重要的临床应用价值. 相似文献
999.
根据目前我国职业病危害的现状,结合冶金矿山主要职业病危害因素及其防治情况,参考国家相关政策与社会发展趋势,论述了开展冶金矿山职业病危害因素控制研究的必要性,并提出了相关的研究方向。 相似文献
1000.
Possemato Kyle; Wade Michael; Andersen Judith; Ouimette Paige 《Canadian Metallurgical Quarterly》2010,2(3):218
Growing evidence suggests that posttraumatic stress disorder (PTSD) is associated with poorer health status (e.g., more medical disease, physical symptoms, and sick visits to health care professionals) among veterans who served in Operation Enduring Freedom (OEF) in Afghanistan and Operation Iraqi Freedom (OIF) in Iraq. We investigated whether PTSD, depression, and substance use disorders independently predicted health status over time among OEF/OIF veterans. Information regarding psychiatric and medical conditions and health care utilization was culled for 4,463 OEF/OIF veterans enrolled in Veterans Administration primary care for a period of 6 years. Data were analyzed using multilevel modeling and generalized estimating equations. Results suggest that PTSD, depression, and substance use disorders are independently associated with increased medical disease burden and mental health care utilization but not increased medical health care utilization. The association between PTSD and medical disease burden strengthened over time. These data suggest that OEF/OIF veterans with PTSD may be at risk for increasingly poorer physical health in terms of medical disease burden over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献