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Objective: Efficacy of neuromuscular electrical stimulation (NMES) is limited by the discomfort of electrically elicited contractions. Most studies of tolerance to NMES have examined stimulation to maximal tolerance. NMES efficiency is the amount of elicited force at a specific level of tolerance. This study is the first to describe and examine such. Design: A repeated measures design was used. Electrically elicited force (EEF) was measured using three waveforms: burst-modulated alternating current (BMAC), pulsed current (PC), and burst-modulated pulsed current (BMPC). EEF at a tolerance rating of 5/10 on a visual analog scale (VAS) was recorded. The dependent variables were EEF up to 5/10 VAS, current amplitude at 5/10, and percent maximal isometric force at 5/10. Results: EEF and percent maximal voluntary isometric force were significantly greater with BMPC versus BMAC (p = 0.001 and 0.004). No differences were noted between PC and BMAC or BMPC and PC. Amplitude was significantly greater with BMAC compared to BMPC and PC (p = 0.003 and 0.015). No difference in amplitude was noted between PC and BMPC. Conclusion: For the same level of discomfort, BMPC yielded one-third greater muscle force than BMAC and at a lesser current amplitude. These data evidence a greater efficiency for BMPC than BMAC.  相似文献   
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Delta-5 (D5D) and delta-6 (D6D) desaturase are key enzymes in fatty acid (FA) metabolism. Dietary eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) may alter tissue FA composition via D5D and D6D. The purpose was to determine the relationship between dietary EPA?+?DHA, estimated desaturase activities of various tissues and the reflection of desaturase activity in the red blood cell (RBC). Mice were fed diets with increasing percent of energy from EPA?+?DHA. Phospholipid FA composition of heart, muscle, spleen, lung, adipose tissues and RBC were analysed. D5D and D6D enzyme activity estimates (EAE) were calculated as the ratio of 20:4/20:3 and 20:3/18:2, respectively. D5D EAE decreased in all tissues, except muscle, with increasing dietary EPA?+?DHA. RBC D5D EAE positively correlated with D5D EAE in all tissues. RBC D6D EAE positively correlated with muscle and inversely correlated with adipose D6D EAE. Our findings suggest differential influence of dietary EPA?+?DHA upon tissue desaturase activities.  相似文献   
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Antidepressants have been associated with weight gain, but the causes are unclear. The aims of this study were to assess the association of antidepressant use with energy intake, macronutrient diet composition, and physical activity. We used data on medication use, energy intake, diet composition, and physical activity for 3073 eligible adults from the 2005–2006 National Health and Nutrition Examination Survey (NHANES). Potential confounding variables, including depression symptoms, were included in the models assessing energy intake, physical activity, and sedentary behavior. Antidepressant users reported consuming an additional (mean ± S.E.) 215 ± 73 kcal/day compared to non-users (p = 0.01). There were no differences in percent calories from sugar, fat, or alcohol between the two groups. Antidepressant users had similar frequencies of walking or biking, engaging in muscle-strengthening activities, and engaging in moderate or vigorous physical activity. Antidepressant users were more likely to use a computer for ≥2 h/day (OR 1.77; 95% CI: 1.09–2.90), but TV watching was similar between the two groups. These results suggest increased energy intake and sedentary behavior may contribute to weight gain associated with antidepressant use. Focusing on limiting food intake and sedentary behaviors may be important in mitigating the weight gain associated with antidepressant use.  相似文献   
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The Institutional Graduate Partnerships Program (GPP) offered by the National Institute of Nursing Research (NINR) provides an exceptional opportunity for students who are enrolled in any PhD program in nursing across the nation to complete dissertation research on the premier research campus of the National Institutes of Health, Bethesda, MD. The goal of this doctoral fellowship program, which is up to 3 years in length, is to train promising doctoral students in basic and clinical research. This knowledge and skill set is necessary for the next generation of nurse scientists to ultimately conduct translational research. In this article, the authors describe the program, eligibility requirements, application procedures, and selection criteria for NINR-supported GPP nursing students. Also provided are tips for interested students and outcomes of current and former NINR-supported GPP students (NINR-GPP).  相似文献   
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Summary

Prolonged incubation revealed that single cells of bottle cultures of HeLa cells may survive even 20 000 r to form colonies of apparently normal cells with unimpaired growth capacity and sensitivity for virus.  相似文献   
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