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排序方式: 共有2545条查询结果,搜索用时 46 毫秒
51.
52.
Simone Ohlwein Frauke Hennig Sarah Lucht Brge Schmidt Lewin Eisele Marina Arendt Ulrich Dührsen Jan Dürig Karl-Heinz Jckel Susanne Moebus Barbara Hoffmann 《Environmental health perspectives》2021,129(2)
Background: Residential exposure to air pollution (AP) has been shown to activate the immune system (IS). Although innate immune responses to AP have been studied extensively, investigations on the adaptive IS are scarce.Objectives: The aim of this study was to investigate the association between short- to long-term AP exposure and polyclonal free light chains (FLC) produced by plasma cells.Methods: We used repeated data from three examinations (: 2000–2003; : 2006–2008; and : 2011–2015) of the population-based German Heinz Nixdorf Recall cohort of initially 4,814 participants (45–75 y old). Residential exposure to total and source-specific particulate matter (PM) with an aerodynamic diameter of 10 or ( and respectively), nitrogen dioxide (), and particle number concentrations (accumulation mode; ) was estimated using a chemistry transport model with different time windows (1- to 365-d mean ± standard deviation) before blood draw. We applied linear mixed models with a random participant intercept to estimate associations between total, traffic- and industry-related AP exposures and log-transformed FLC, controlling for examination time, sociodemographic and lifestyle variables, estimated glomerular filtration rate and season.Results: Analyzing 9,933 observations from 4,455 participants, we observed generally positive associations between AP exposures and FLC. We observed strongest associations with middle-term exposures, e.g., 3.0% increase in FLC (95% confidence interval: 1.8%, 4.3%) per interquartile range increase in 91-d mean of (). Across the different pollutants, showed strongest associations with FLC, followed by and . Effect estimates for traffic-related exposures were mostly higher compared with total exposures. Although and estimates remained stable upon adjustment for PM, PM estimates decreased considerably upon adjustment for and .Discussion: Our results suggest that middle-term AP exposures in particular might be positively associated with activation of the adaptive IS. Traffic-related PM, , and showed strongest associations. https://doi.org/10.1289/EHP7164 相似文献
53.
Allison J. Lazard Anthony Dudo Tessa Dennis Mary Grace Ewald Brad Love 《Health communication》2017,32(4):470-482
Understanding the influence of visual design, as the access point for online health communication, is key as Americans are increasingly sickened by an obesity epidemic. Nutritional websites that deliver critical health information should be considered as a potential strategy to fight against the grave consequences of obesity, as research indicates that consumers are consistently turning to the Internet as a resource for health information. Focusing on nutritional websites, this study analyzes the use of visual design principles that are known to greatly influence first impressions and appeal of the information from the user’s perspective. The results suggest there are opportunities for improvement to the online communication of nutritional information to increase the likelihood of users’ favorable first impressions, the critical first steps for nutritional information delivery goals. 相似文献
54.
M. Haas P. Ullmann J. T. Schneider H. Post W. Ruhm J. Hennig M. Zaitsev 《Magnetic resonance in medicine》2013,70(5):1220-1228
With the recent proposal of using magnetic fields that are nonlinear by design for spatial encoding, new flexibility has been introduced to MR imaging. The new degrees of freedom in shaping the spatially encoding magnetic fields (SEMs) can be used to locally adapt the imaging resolution to features of the imaged object, e.g., anatomical structures, to reduce peripheral nerve stimulation during in vivo experiments or to increase the gradient switching speed by reducing the inductance of the coils producing the SEMs and thus accelerate the imaging process. In this work, the potential of nonlinear and nonbijective SEMs for spatial encoding during transmission in multidimensional spatially selective excitation is explored. Methods for multidimensional spatially selective excitation radiofrequency pulse design based on nonlinear encoding fields are introduced, and it is shown how encoding ambiguities can be resolved using parallel transmission. In simulations and phantom experiments, the feasibility of selective excitation using nonlinear, nonbijective SEMs is demonstrated, and it is shown that the spatial resolution with which the target distribution of the transverse magnetization can be realized varies locally. Thus, the resolution of the target pattern can be increased in some regions compared with conventional linear encoding. Furthermore, experimental proof of principle of accelerated two‐dimensional spatially selective excitation using nonlinear SEMs is provided in this study. Magn Reson Med 70:1220–1228, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
55.
Ewald Ornstein Herbert Franzén Ragnar Johnsson Martin Sundberg 《Acta orthopaedica》2013,84(4):360-364
We revised the hip (6 stems and 5 sockets) with impacted morselized allografts and cement in 6 patients. We followed prosthetic migration by roentgen radiostereometric analysis (RSA) every 7th day for 6 weeks after the first (index) examination performed on the first postoperative day before mobilization. Most of the migration occurred during the first 2 weeks. In most cases more than half of the distal stem migration was seen between the 1st and 14th days. In all cases, the stem and socket migrations slowed down gradually and several prosthetic components had become stable after 5 weeks. We conclude that it is essential to perform the index RSA examination on the 1st or 2nd day after surgery and to state when and how weight bearing should be permitted. Otherwise it will be difficult to compare prosthetic migration in various studies and define normative values for migration predicting survival. 相似文献
56.
Regula J Hennig E Burzykowski T Orlowska J Przytulski K Polkowski M Dziurkowska-Marek A Marek T Nowak A Butruk E Ostrowski J 《Digestion》2003,67(1-2):25-31
BACKGROUND: Although Helicobacter pylori is a significant etiologic factor of peptic ulcer disease, it remains unknown why ulcers develop only in the minority of infected individuals. AIM: The aim of this cross-sectional study was to evaluate the association between the presence of duodenal ulcer in H. pylori-infected patients and different risk factors. METHODS: A total of 122 H. pylori-infected patients were enrolled; 79 had duodenal ulcer and 43 gastritis. Univariate analysis was conducted using either Fisher's exact test or exact Cochrane-Armitage trend test. In multivariate analysis the logistic model was used. RESULTS: Univariate analysis indicated six factors (male sex, smoking, antral H. pylori density, CAGA presence in antrum, and VACA s1a presence in antrum and corpus). Four factors (sex, smoking-alcohol index, H. pylori density index, and CAGA index) were found to be significant in multivariate analysis. The best model predicting duodenal ulcer included male sex, smoking, presence of H. PYLORI on histopathology in antrum and CAGA presence in corpus. CONCLUSION: Although several risk factors were significantly associated with duodenal ulcer, we failed in the identification of either a single risk factor or a set of factors that can unequivocally differentiate patients with ulcer from those with gastritis. 相似文献
57.
Genome-wide array analysis of normal and malformed human hearts 总被引:1,自引:0,他引:1
58.
Katherine R. Amato Marie-Claire Arrieta Meghan B. Azad Michael T. Bailey Josiane L. Broussard Carlijn E. Bruggeling Erika C. Claud Elizabeth K. Costello Emily R. Davenport Bas E. Dutilh Holly A. Swain Ewald Paul Ewald Erin C. Hanlon Wrenetha Julion Ali Keshavarzian Corinne F. Maurice Gregory E. Miller Geoffrey A. Preidis Laure Segurel Burton Singer Sathish Subramanian Liping Zhao Christopher W. Kuzawa 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(25)
Individuals who are minoritized as a result of race, sexual identity, gender, or socioeconomic status experience a higher prevalence of many diseases. Understanding the biological processes that cause and maintain these socially driven health inequities is essential for addressing them. The gut microbiome is strongly shaped by host environments and affects host metabolic, immune, and neuroendocrine functions, making it an important pathway by which differences in experiences caused by social, political, and economic forces could contribute to health inequities. Nevertheless, few studies have directly integrated the gut microbiome into investigations of health inequities. Here, we argue that accounting for host–gut microbe interactions will improve understanding and management of health inequities, and that health policy must begin to consider the microbiome as an important pathway linking environments to population health. 相似文献
59.
Agabiti-Rosei E Trimarco B Muiesan ML Reid J Salvetti A Tang R Hennig M Baurecht H Parati G Mancia G Zanchetti A;ELSA Echocardiographic Substudy Group 《Journal of hypertension》2005,23(5):1091-1098
OBJECTIVES: To evaluate and correlate the effects of long-term antihypertensive treatment on left ventricular (LV) mass and carotid structural changes in a large group of essential hypertensive patients, participating in the European Lacidipine Study on Atherosclerosis (ELSA). DESIGN: In four (Brescia, Glasgow, Naples and Pisa) of 23 centres participating in the ELSA study, an echocardiographic examination was performed at baseline and repeated, until the end of the 4-year study, in essential hypertensive patients, followed-up for carotid quantitative ultrasound examination of intima-media thickness (IMT), after random allocation to treatment with either lacidipine or atenolol (and added hydrochlorothiazide, as required for control of blood pressure). METHODS: M-mode, two-dimensional guided echocardiography was used to measure left ventricular (LV) wall thickness and dimensions, from which LV mass was calculated, using an anatomically validated formula (Penn Convention) and indexed to body surface area (left ventricular mass index, LVMI). The echocardiographic tracings were blindly evaluated in a single reading centre (Brescia). Bilateral IMT was measured at the site of common carotid and bifurcation far walls (CBMmax). RESULTS: At baseline, cardiac and carotid ultrasound scans were available in 278 patients (mean age 54 +/- 7 years, 57% males, 22% obese). A significant correlation was observed between baseline LVMI and CBMmax (r = 0.22, P < 0.001), independent of age. In multivariate analysis, CBMmax and mean 24-h pulse pressure were most strongly associated with baseline LVMI. A significant reduction in LVMI was observed both during lacidipine (n = 96) (-12.5% reduction) and atenolol (n = 78) (-13.9% reduction) treatments (up to 4 years) (P < 0.001 for both, without significant differences between treatments). Changes in LVMI were not related to changes in carotid wall thickness. In multivariate analysis, baseline LV mass and mean 24-h systolic blood pressure changes were significantly associated with changes in LV mass. CONCLUSIONS: In this large, long-term controlled study, antihypertensive treatment with atenolol or lacidipine was accompanied by a similar and significant decrease in LV mass. Treatment-induced changes in LV mass were related to baseline LV mass and changes in 24-h mean systolic blood pressure, without any correlation with changes in carotid structure. In the whole ELSA population, carotid IMT changes have been shown to be unrelated to blood pressure reduction, but significantly influenced by the type of antihypertensive treatment. 相似文献
60.