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51.
Jeffrey W. Ryder Roxanne E. Buxton Elizabeth Goetchius Melissa Scott-Pandorf Kyle J. Hackney James Fiedler Robert J. Ploutz-Snyder Jacob J. Bloomberg Lori L. Ploutz-Snyder 《European journal of applied physiology》2013,113(4):911-921
Existing models of muscle deconditioning such as bed rest are expensive and time-consuming. We propose a new model utilizing a weighted suit to manipulate muscle strength, power, or endurance relative to body weight. The aims of the study were to determine as to which muscle measures best predict functional task performance and to determine muscle performance thresholds below which task performance is impaired. Twenty subjects performed seven occupational astronaut tasks (supine and upright seat egress and walk, rise from fall, hatch opening, ladder climb, object carry, and construction board activity), while wearing a suit weighted with 0–120 % of body weight. Models of the relationship between muscle function/body weight and task completion time were developed using fractional polynomial regression and verified with pre- and post-flight astronaut performance data. Spline regression was used to identify muscle function thresholds for each task. Upright seat egress and walk was the most difficult task according to the spline regression analysis thresholds. Thresholds normalized to body weight were 17.8 N/kg for leg press isometric force, 17.6 W/kg for leg press power, 78.8 J/kg for leg press work, 5.9 N/kg isometric knee extension and 1.9 Nm/kg isokinetic knee extension torque. Leg press maximal isometric force/body weight was the most reliable measure for modeling performance of ambulatory tasks. Laboratory-based manipulation of relative strength has promise as an analog for spaceflight-induced loss of muscle function. Muscle performance values normalized to body weight can be used to predict occupational task performance and to establish relevant strength thresholds. 相似文献
52.
Cynthia Tsien Huey Tan Sowmya Sharma Naaventhan Palaniyappan Pramudi Wijayasiri Kristel Leung Jatinder Hayre Elizabeth Mowlem Rachel Kang Peter J Eddowes Emilie Wilkes Suresh V Venkatachalapathy Indra N Guha Lilia Antonova Angela C Cheung William JH Griffiths Andrew J Butler Stephen D Ryder Martin W James Guruprasad P Aithal Aloysious D Aravinthan 《Clinical medicine (London, England)》2021,21(1):e32
53.
Modern population based oral health management requires a complete understanding of the impact of disease in order to provide efficient and effective oral health care and guidance. Periodontitis is an important cause of tooth loss and has been shown to be associated with a number of systemic conditions. The impact of oral conditions and disorders on quality of life has been extensively studied. However, the impact of periodontitis on quality of life has received less attention. This review summarizes the literature on the impact of periodontitis on oral health‐related quality of life (OHRQoL). Relevant publications were identified after searching the MEDLINE and EMBASE electronic databases. Screening of titles and abstracts and data extraction was conducted. Only observational studies were included in this review. Most of the reviewed studies reported a negative impact of periodontitis on OHRQoL. However, the reporting standards varied across studies. Moreover, most of the studies were conducted in developed countries. 相似文献
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BRIDGE 2 (Building the Relationship Between Body Image and Disordered Eating Graph and Explanation): Interventions and Transitions, builds upon the framework presented in the first publication of BRIDGE. BRIDGE 2 moves beyond increasing the understanding of the relationship between body image and eating disorders and encourages a movement into action. First, it suggests the appropriate point of intervention for both parents and teachers. Second, the continuum of health care from promotion to prevention, to early intervention, and to basic and specialized treatment services is positioned on the BRIDGE framework. This added dimension offers a new level of understanding specific to eating disorders by utilizing concepts from mental health promotion and mental illness prevention literature. 相似文献
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Type 2 diabetes, the most common form of diabetes, is characterized by abnormalities in hepatic glucose production, insulin resistance, and a progressive decline in beta-cell function over time. To treat effectively the individual with type 2 diabetes, the provider must have a thorough understanding of the underlying pathophysiology to provide treatment that precisely addresses the metabolic abnormalities. Currently, the provider who cares for subjects with type 2 diabetes can choose an antidiabetic agent from no less than eight pharmacologic classes. These classes include agents that increase insulin secretion, improve insulin action, and delay absorption of carbohydrates. The newer treatments available, specifically incretin therapy, address a previously unmet need in diabetes by modulating glucose supply. The currently available agents can be combined and combination therapy markedly improves glycemic control. This allows the provider to design regimens to specifically address underlying abnormalities. A review of all currently available agents is provided. 相似文献
59.
JR Pallett E Sutherland E Glucksman M Tunnicliff JW Keep 《Annals of the Royal College of Surgeons of England》2014,96(1):23-26
INTRODUCTION
No national recording systems for knife injuries exist in the UK. Understanding the true size and nature of the problem of knife injuries is the first stage in reducing the burden of this injury. The aim of this study was to survey every knife injury seen in a single inner city emergency department (ED) over a one-year period.METHODS
A cross-sectional observational study was performed of all patients attending with a knife injury to the ED of a London major trauma centre in 2011. Demographic characteristics, patterns of injury, morbidity and mortality data were collected.RESULTS
A total of 938 knife injuries were identified from 127,191 attendances (0.77% of all visits) with a case fatality rate of 0.53%. A quarter (24%) of the major trauma team’s caseload was for knife injuries. Overall, 44% of injuries were selfreported as assaults, 49% as accidents and 8% as deliberate self-harm. The highest age specific incident rate occurred in the 16–24 year age category (263/100,000). Multiple injuries were seen in 19% of cases, of which only 81% were recorded as assaults. The mean length of stay for those admitted to hospital was 3.04 days. Intrathoracic injury was seen in 26% of cases of chest trauma and 24% of abdominal injuries had a second additional chest injury.CONCLUSIONS
Violent intentional injuries are a significant contributory factor to the workload of the major trauma team at this centre. This paper contributes to a more comprehensive understanding of the nature of these injuries seen in the ED. 相似文献60.
Hydroxyurea-induced augmentation of fetal hemoglobin production in patients with sickle cell anemia 总被引:3,自引:4,他引:3
Five patients with sickle cell anemia were treated with hydroxyurea (HU), in hopes of augmenting their production of fetal hemoglobin. Laboratory responses in two patients treated for more than 2 years were encouraging and there were suggestions of clinical improvement. Long- term HU therapy should be considered for severely affected adults with sickle cell anemia who are willing to accept what is probably a small risk of carcinogenesis. Preliminary chromosomal analysis and knowledge of the clastogenic properties of HU suggest that conception and pregnancy should be avoided. Pharmacokinetic studies will probably be necessary to adjust individual dosage schedules so that cytotoxicity is avoided. F cell responses can be seen in 2 to 3 weeks if the HU dose is optimal, but establishment of a large number of F cells in the circulation may take a month or longer. 相似文献