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991.
Purpose: Given the prevalence of physical inactivity among American adults, convenient, low-cost interventions are strongly indicated. This study determined the 6- and 12-month effectiveness of telephone interventions delivered by health educators or by an automated computer system in promoting physical activity. Design: Initially inactive men and women age 55 years and older (N = 218) in stable health participated. Participants were randomly assigned to human advice, automated advice, or health education control. Measures: The validated 7-day physical activity recall interview was used to estimate minutes of moderate to vigorous physical activity. Physical activity differences by experimental arm were verified on a random subsample via accelerometry. Results: Using intention-to-treat analysis, at 6 months, participants in both interventions, although not differing from one another, showed significant improvements in weekly physical activity compared with controls. These differences were generally maintained at 12 months, with both intervention arms remaining above the target of 150 min per week of moderate to vigorous physical activity on average. Conclusion: Automated telephone-linked delivery systems represent an effective alternative for delivering physical activity advice to inactive older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
Interleaving technique is used in some applications due to its advantages regarding filter reduction, dynamic response, and power management. In dual battery system vehicles, the bidirectional dc-dc converter takes advantage of this technique using three-to-five paralleled buck stages. In this paper, we propose the use of a much higher number of phases in parallel together with digital control. It will be shown that this approach opens new possibilities since changes in the technology are possible. Thus, two 1000-W prototypes have been designed using surface mount technology devices (SO-8 transistors). An additional important feature is that due to the accuracy of the digital device [field-programmable gate array (FPGA)], current loops have been eliminated, greatly simplifying the implementation of the control stage.  相似文献   
993.
This paper describes a simple flow-injection (FI) manifold for the determination of a variety of species in industrial water. The chemical systems involved in the determination of ammonia (formation of Indophenol Blue), sulfate (precipitation with Ba(II)), and iron (complexation with 1,10-phenanthroline with the help of a prior redox reaction for speciation) were selected so that a common manifold could be used for the sequential determination of batches of each analyte. A microcolumn of a suitable ion exchange material was used for on-line preconcentration of each analyte prior to injection; linear ranges for the determination of the analytes at the ng/ml levels were obtained with good reproducibility. The manifold and methods are ready for full automation.  相似文献   
994.
The clinical appearance of celiac disease is diverse, often times uncharacteristic and may therefore be very difficult to diagnose. Furthermore, severe inflammation of the small bowel can be present without gastrointestinal symptoms. It is estimated that most subjects with celiac disease are not diagnosed. Yet, early diagnose is desirable, since celiac disease causes growth retardation in untreated children and is potentially cancer disposing. Thus, all patients should adhere to a strict gluten-free diet. The role of antibody testing and small bowel biopsy in celiac disease will be discussed. In the future, the development of new tests may allow screening of large populations.  相似文献   
995.
Eukaryotic elongation factor 1alpha (eEF-1A) is a multifunctional protein. There are three known posttranslational modifications of eEF-1A that could potentially affect its function. Except for phosphorylation, the other posttranslational modifications have not been demonstrated in plants. Using matrix-assisted laser desorption/ionization-mass spectrometry and peptide mass mapping, we show that carrot (Daucus carota L.) eEF-1A contains a phosphoglycerylethanolamine (PGE) posttranslational modification. eEF-1A was the only protein labeled with [14C]ethanolamine in carrot cells and was the predominant ethanolamine-labeled protein in Arabidopsis seedlings and tobacco (Nicotiana tabacum L.) cell cultures. In vivo-labeling studies using [3H]glycerol, [32P]Pi, [14C]myristic acid, and [14C]linoleic acid indicated that the entire phospholipid phosphatidylethanolamine is covalently attached to the protein. The PGE lipid modification did not affect the partitioning of eEF-1A in Triton X-114 or its actin-binding activity in in vitro assays. Our in vitro data indicate that this newly characterized posttranslational modification alone does not affect the function of eEF-1A. Therefore, the PGE lipid modification may work in combination with other posttranslational modifications to affect the distribution and the function of eEF-1A within the cell.  相似文献   
996.
This paper focuses on a class of multiaxial fatigue limit criteria where the equivalent shear stress amplitude is calculated by means of a scalar measure associated with a hypersurface enclosing the deviatoric stress history at a material point. We consider two hypersurfaces proposed by the authors, namely the maximum prismatic hull and the minimum Frobenius norm ellipsoid. Previous results obtained with elliptic and non-elliptic stress paths strongly suggested that such measures might always be the same. In this work we consider two counter-examples which show that these approaches are distinct. Fatigue limit criteria based on the linear combination of these measures with the maximum hydrostatic stress were applied to experimental data including: axial–torsional, biaxial tension and plane stress tests performed under harmonic and non-harmonic, synchronous and asynchronous waveforms. The predictions for both criteria fell within a 15% scatter band.  相似文献   
997.
Reperfusion therapy has contributed to decreased morbidity and mortality in patients with acute myocardial infarction (AMI). Implementation of thrombolytic therapy; primary angioplasty and emergency coronary artery by-pass surgery have proved to be effective in well designed controlled clinical trials. There is little information, however, about the impact of reperfusion therapy in the general clinical population that is usually seen in the coronary care unit. In this paper we have compared the clinical course, morbidity and mortality of patients attended for a first AMI in 2 different periods. Group I comprised 431 patients seen during the period 1981-1986 and group II bad 113 patients seen during the period 1992-1993. Age, gender distribution and AMI location were similar in both groups. Patients in group I had a significantly higher incidence of tobacco use and previous angina pectoris. In group I, 4% of patients received streptokinase, 0.9% of patients had emergency by-pass surgery and none had primary angioplasty, whereas in group II, 29% of patients received trombolytics, 6.5% had primary angioplasty and 6.5% had by-pass surgery. Heart failure Killip class II-III occurred in 35% of patients in group I and in 13% of patients in group II (p < 0.05). Intrahospital mortality was 19.6% in group I and 11.5% in Group II (p < 0.045). There were no differences in the incidence of cardiogenic shock in both groups. Multivariate analysis showed that age and heart failure were significant independent predictors of mortality in both periods. Thus, there has been a significant change in the therapeutic approach to AMI patients in recent years. Widespread utilization of reperfusion therapy appears to be associated with decrease in morbidity and mortality in a general population of patients with a first AMI.  相似文献   
998.
999.
Solar dried pears of the “S. Bartolomeu” variety are a very much appreciated and preferred dried food product in Portugal. Nevertheless, the traditional solar drying is carried out at open air during the months of 07 and 08, and this nowadays is a disadvantage for larger productions. This work is to evaluate the possibility of producing dried pears from this and other varieties, maintaining the characteristics of the traditional dried pears. In this study four different types of pears were studied, including “S. Bartolomeu” as a basis for comparison and the drying method employed was the traditional one. From the results it was concluded that, although the behaviour of the four varieties do not vary significantly, one particular variety (“D. Joaquina”) is a good alternative to the “S. Bartolomeu” pear.  相似文献   
1000.
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