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排序方式: 共有381条查询结果,搜索用时 15 毫秒
41.
W Koenig M Sund B Filipiak A D?ring H L?wel E Ernst 《Canadian Metallurgical Quarterly》1998,18(5):768-772
Plasma viscosity is determined by various macromolecules, eg, fibrinogen, immunoglobulins, and lipoproteins. It may therefore reflect several aspects involved in cardiovascular diseases, including the effects of classic risk factors, hemostatic disturbances, and inflammation. We examined the association of plasma viscosity with the incidence of a first major coronary heart disease event (CHD; fatal and nonfatal myocardial infarction and cardiac death; n=50) in 933 men aged 45 to 64 years of the MONICA project of Augsburg, Germany. The incidence rate was 7.23 per 1000 person-years (95% confidence interval [CI], 5.37 to 9.53), and the subjects were followed up for 8 years. All suspected cases of an incident CHD event were classified according to the MONICA protocol. There was a positive and statistically significant unadjusted relationship between plasma viscosity and the incidence of CHD. The relative risk of CHD events associated with a 1-SD increase in plasma viscosity (0.070 mPa x s) was 1.60 (95% CI, 1.25 to 2.03). After adjustment for age, total cholesterol, high density lipoprotein cholesterol, smoking, blood pressure, and body mass index, the relative risk was reduced only moderately (1.42; 95% CI, 1.09 to 1.86). The relative risk of CHD events for men in the highest quintile of the plasma viscosity distribution in comparison with the lowest quintile was 3.31 (95% CI, 1.19 to 9.25) after adjustment for the aforementioned variables. A large proportion of events (40%) occurred among men in the highest quintile. These findings suggest that plasma viscosity may have considerable potential to identify subjects at risk for CHD events. 相似文献
42.
The impact of a media campaign in the reduction of risk-taking behavior on the part of drivers 总被引:1,自引:0,他引:1
As part of an ongoing media educational campaign to enhance pedestrian safety in the Victoria (Canada) metropolitan area, multimedia campaigns have been targeted at drivers. This paper evaluates the campaign that focused on encouraging left-turning drivers to yield. Observers monitored five signalized intersections during five separate weeks. Logistic regression analyses indicate that this media campaign produced a long-term effect of increasing drivers' yielding behaviors. 相似文献
43.
PURPOSE: The purpose of this study was to compare the fractional contributions of the three pathways of lactate transport (band 3 system, nonionic diffusion, and monocarboxylate pathway) into red blood cells (RBC) from trained and untrained humans. METHODS: Blood samples were obtained from 19 male subjects: 5 untrained, 5 aerobically-trained, 5 competitive collegiate cross-country runners, and 4 competitive collegiate sprinters. The influx of lactate into the RBC was measured by a radioactive tracer technique using [14C]lactate. Discrimination of each pathway of lactate transport was achieved by using PCMBS (1 mM) to block the monocarboxylate pathway and DIDS (0.2 mM) to block the band 3 system. Nonionic diffusion was calculated as the difference between total lactate influx and the sum of band 3 and monocarboxylate lactate influx. RESULTS: Total lactate influx into the RBC from the more aerobic individuals (trained subjects and cross-country runners) was significantly faster at 1.6 mM lactate concentration ([La]) as compared with the influx into RBC of the untrained subjects. Total influx of lactate was significantly higher (P < 0.05) in the RBC from the sprinters as compared with that in the RBC from the untrained subjects at 41 mM [La]. There were no significant differences among the four groups with regard to the total influx of lactate at 4.1, 8.1, and 20 mM [La]. In general, the percentage of total lactate influx accounted for by each of the three parallel pathways at 1.6, 8.1, and 41.0 mM [La] was not different among the four groups of subjects. CONCLUSIONS: Overall, the groups were more similar than different with regard to RBC lactate influx. 相似文献
44.
We studied the in vitro effects of peritoneal dialysis fluids (PDF) containing 1 and 1.5% amino acids (AA) as compared to approximately equiosmolar glucose (GLU)-based PDF (1.5 and 4.25%) and control buffer, respectively, on peritoneal macrophage (PMO) function. The media were tested at original pH (5.3-5.5) and after pH adjustment to 7.4. PMO were isolated from the effluents of 10 on continuous ambulatory peritoneal dialysis (CAPD) patients and tested for luminol- and lucigenin-enhanced chemiluminescence (CL), superoxide generation measured by cytochrome c reduction, killing capacity and phagocytosis after incubation (30 min, 37 degrees C) in the PDF used. All AA-based PDF exhibited a statistically significant depressive effect on integral CL response, O2- production and bacterial killing of PMO at pH 7.4 in comparison with pH-adjusted GLU-based PDF of similar osmolality and buffer. Exposure of PMO to acidic AA-based media did not result in a significantly different suppression of the oxidative metabolism and the killing capacity as compared to fresh GLU-based fluids. Phagocytosis of PMO did not show significant differences after incubation in the solutions studied. Thus, the AA-based PDF employed compromise the oxidative metabolism and the killing capacity of PMO at pH 7.4 in vitro significantly more than GLU-based fluids. Since pH-identical and almost equiosmolar PDF were compared, the specific composition of the AA-based fluids, especially the high content of lactate and several essential AA, could be responsible for this detrimental impact. 相似文献
45.
Wang J. Hays P.B. Drayson S.R. Koenig E.W. 《Geoscience and Remote Sensing, IEEE Transactions on》1993,31(1):80-89
A technique based on the Fabry-Perot interferometer for measuring atmospheric temperature, moisture, and other trace species with high spectral resolution from satellite is described. The key technologies incorporated into the remote sensing technique and instrument design include high spectral resolution through the use of a Fabry-Perot interferometer (FPI), high sensitivity through multiplexing of orders, the use of an innovative FPI focal plane detection technique called the Circle to Line Interferometer Optical system, and the simultaneous sampling of all spectral bands and channels. Studies show that the Multiorder Etalon Sounder is feasible and can greatly improve the sounding capability of present infrared atmospheric sounders 相似文献
46.
Dynamic X-ray computed tomography 总被引:1,自引:0,他引:1
Bonnet S. Koenig A. Roux S. Hugonnard P. Guillemaud R. Grangeat P. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2003,91(10):1574-1587
Dynamic computed tomography (CT) imaging aims at reconstructing image sequences where the dynamic nature of the living human body is of primary interest. The main applications concerned are image-guided interventional procedures, functional studies and cardiac imaging. The introduction of ultra-fast rotating gantries along with multi-row detectors and in near future area detectors allows huge progress toward the imaging of moving organs with low-contrast resolution. This paper gives an overview of the different concepts used in dynamic CT. A new reconstruction algorithm based on a voxel-specific dynamic evolution compensation is also presented. It provides four-dimensional image sequences with accurate spatio-temporal information, where each frame is reconstructed using a long-scan acquisition mode on several half-turns. In the same time, this technique permits to reduce the dose delivered per rotation while keeping the same signal to noise ratio for every frame using an adaptive motion-compensated temporal averaging. Results are illustrated on simulated data. 相似文献
47.
HG Koenig JC Hays LK George DG Blazer DB Larson LR Landerman 《Canadian Metallurgical Quarterly》1997,5(2):131-144
The authors examined models of the relationships between religious activities, physical health, social support, and depressive symptoms in a sample of 4,000 persons age 65 and over. Religious activity was examined first as a single composite construct and then split into three component variables that were examined individually. Religious activity as a single construct was correlated with both social support and good physical health but was unrelated to depression. Split into the three components, model fit was significantly increased. Frequency of church attendance was positively related to physical health and negatively related to depression, but was surprisingly unrelated to social support. Frequent churchgoers were about half as likely to be depressed. Private prayer/Bible reading was negatively correlated with physical health and positively correlated with social support, but unrelated to depression. Religious TV/radio listening was unrelated to social support, negatively related to good physical health, and, unexpectedly, positively associated with depression. 相似文献
48.
Endocytosis and recycling of G protein-coupled receptors 总被引:1,自引:0,他引:1
Agonist stimulation of G protein-coupled receptors causes a dramatic reorganization of their intracellular distribution. Activation of receptors triggers receptor endocytosis and, since receptors recycle back to the surface continuously, a new steady state is reached where a significant proportion of receptors is located internally. Although this movement of receptors is remarkable, its role has been enigmatic. Recent developments have provided insight into the compartments through which the receptors move, the nature of the signals that trigger receptor translocation, and the significance of receptor cycling for cell function. In this article, Jennifer Koenig and Michael Edwardson review recent progress in this field and place receptor cycling into a mathematical framework that reveals the extent and rate of intracellular receptor movement. 相似文献
49.
Nuclear Magnetic Resonance Imaging (NMRI) was used to analyze the curing behavior of epoxy adhe-sives in the presence of anodized and chemically-treated aluminum surfaces. The proton images of epoxy between untreated AI plates are characterized by large amounts of inhomogeneities (fine texture of high and low mobility regions) finely distributed throughout the sample. Large uncured domains of epoxy were found aggregated and near the center of the bonded adhesive sample. Dispersion of uncured material during curing is observed through redistribution of intensity in the images with cure time. The anodized aluminum-epoxy samples, on the other hand, showed very small contrast and coarse texture images. However, the onset of curing was clearly shown with increases in contrast and texture. Large amounts of uncured material were seen near the anodized surfaces. This effect was more pronounced in the chromic acid anodized aluminum samples (CAA). 相似文献
50.
According to this review, religion plays a largely positive role in mental health; future research on severe mental disorders should include religious factors more directly. 相似文献