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101.
Johnson NA Walton DW Sachinwalla T Thompson CH Smith K Ruell PA Stannard SR George J 《Hepatology (Baltimore, Md.)》2008,47(5):1513-1523
Nonalcoholic fatty liver is frequently observed in obese individuals, yet the factors that predict its development and progression to liver disease are poorly understood. We proposed that proton magnetic resonance spectroscopy ((1)H-MRS) might allow noninvasive assessment of hepatic lipid composition. Lipid saturation (SI) and polyunsaturation (PUI) indices measured by (1)H-MRS were in agreement with those expected in oils of known composition. Hepatic triglyceride concentration (HTGC) and composition were then measured in healthy lean (LEAN) men, obese men with normal HTGC (OB), and obese men with hepatic steatosis (OB+HS). The effect of marked changes in dietary fat consumption on hepatic lipids were also compared in lean men after 67 hours of a normal mixed (NM) diet versus a low-carbohydrate, high-saturated-fat (LCHF) diet. SI was significantly higher in OB+HS (0.970 +/- 0.004) and OB (0.944 +/- 0.008) versus LEAN (0.818 +/- 0.025) (P < 0.01 for both). PUI was significantly lower in OB+HS (0.003 +/- 0.001) and OB (0.022 +/- 0.005) versus LEAN (0.120 +/- 0.021) (P < 0.01), and significantly lower in OB+HS versus OB (P < 0.05). LCHF diet did not alter HTGC, SI, or PUI (P > 0.05). The (1)H-MRS method provides for rapid, qualitative assessment of lipid composition. Application of this technique in the liver produces results that are consistent with biopsy-based approaches demonstrating that relative hepatic lipid saturation increases and polyunsaturation decreases with obesity. Obesity-related hepatic steatosis is characterized by further depletion of polyunsaturated hepatic lipids. CONCLUSION: This readily available and noninvasive approach should promote further study into interactions between hepatic and whole-body lipid metabolism and help to elucidate the pathogenesis of disorders characterized by lipid accumulation within the liver. 相似文献
102.
The glycoprotein (GP) Ib-IX complex mediates platelet aggregation in response to high shear forces by binding von Willebrand factor (vWF) in the plasma. We investigated the possibility that the complex could mediate a similar phenomenon if expressed in nonhematopoietic cells. When agitated on a tabletop shaker, CHO and L cells expressing the full complex formed large aggregates in the presence of vWF and the modulator ristocetin. When the rate of agitation was increased, aggregation occurred without added ristocetin and appeared to require only the application of a physical force. The aggregation was homophilic and temperature-dependent and required a functional ligand- binding subunit of the GP Ib-IX complex, GP Ib alpha. Posttranslational tyrosine sulfation of GP Ib alpha was required for aggregate formation and stability. Thus, aggregation of cells expressing the GP Ib-IX complex is a unique example of a ligand-receptor interaction induced by mechanical forces and demonstrates an important biological role for sulfation of tyrosine residues. 相似文献
103.
Anne Mandy Claire Walton Jon Michaelis 《Disability and rehabilitation. Assistive technology》2015,10(2):108-112
Aims: This pilot study measured activities of daily living performance in individuals/participants with hemiplegia propelling both a standard dual handrim Action 3 wheelchair and a standard Action 3 wheelchair with a Neater Uni-Wheelchair kit attachment. The kit consists of a steerable front. Research questions: Does the use of the NUW affect the performance quality of activities of daily living in individuals/participants with hemiplegia. Is there a difference in the motor and process skills during activities of daily living performance, and in the time taken to complete the activities. Methods: Four individuals/participants with hemiplegia were used in a cross over, repeated measures trial. Assessment of Motor and Process Skills of users undertaking making a bed and laying a table “Swedish style”, tasks were measured and time taken to complete each task were recorded. Results: Bed making completion time was quicker in the Neater Uni-wheelchair (p?0.03). Motor skills were significantly higher than the process ability skills (p?0.05). Conclusion: Activities of daily living tasks in the Neater Uni-wheelchair were completed more efficiently with no loss in quality of motor and process skills performance. This suggests that the Neater Uni-wheelchair is a viable alternative to current one arm drive provision.
- Implications for Rehabilitation
Inappropriate wheelchair provision can result in capacity limitation and poorer quality of ADL motor skill as well-lowered process performance skill.
AMPS can help to explain motor and process skill differences in complex activities.
104.
Diagnostic value of biparametric magnetic resonance imaging (MRI) as an adjunct to prostate‐specific antigen (PSA)‐based detection of prostate cancer in men without prior biopsies 下载免费PDF全文
Soroush Rais‐Bahrami M. Minhaj Siddiqui Srinivas Vourganti Baris Turkbey Ardeshir R. Rastinehad Lambros Stamatakis Hong Truong Annerleim Walton‐Diaz Anthony N. Hoang Jeffrey W. Nix Maria J. Merino Bradford J. Wood Richard M. Simon Peter L. Choyke Peter A. Pinto 《BJU international》2015,115(3):381-388
105.
Shofiq Islam Muhiuddin AhmedGary M. Walton Timothy G. DinanGary R. Hoffman 《Journal of cranio-maxillo-facial surgery》2012,40(1):82-85
Aim
The potential psycho-social sequelae of traumatic facial injury have received increasing attention in recent years, however there remains paucity of cross-national comparative data on the prevalence of psychological distress following such trauma. The aim of the present study was to investigate and compare the prevalence of anxiety and depression in an adult patient group who have been treated for maxillofacial trauma, and who attend a follow-up clinic in either the West Midlands, UK or New South Wales (NSW), Australia. By using an identical methodological and statistical approach, we hoped to add to the available information on the incidence of early psychological distress in patients following facial trauma.Method
This was a comparative cross-sectional study. A sample of fifty consecutive adult victims of facial trauma in the West Midlands UK, was compared to a group of fifty-two facially injured patients in NSW, Australia. Demographic data was collected, following which the Hospital Depression and Anxiety Scale (HADS) were applied to both groups of patients.Results
Psychometric scores suggestive of anxiety and depressive state were common in both groups of patients. The mean HADS depression subscale score for UK patients compared to Australian patients was not significantly different (5.94 versus 5.54 p = 0.62). This was also the case for the HADS anxiety subscale (5.96 versus 5.94 p = 0.98). Although the number of patients achieving scores suggestive of a ‘caseness’ for co-morbid psychological state was higher within the UK sample when compared to the Australian group (20% versus 11.5% for HADS depression subscale, and 20% versus 15% for HADS anxiety subscales respectively); these differences did not reach statistical significance.Conclusion
This cross-national comparative study has shown that anxiety and depression in facial trauma victims were comparable in both settings. 相似文献106.
107.
Renée J. McCarter Nigel H. Walton D. Neil Brooks Graham E. Powell 《The Clinical neuropsychologist》2013,27(6):1050-1066
A survey of members of the British Psychological Society Division of Neuropsychology (N = 588) was conducted via email to ascertain current practice with respect to the use of symptom validity testing (SVT) in clinical and legal neuropsychological assessments. Replies were received from 130 practicing neuropsychologists. Results showed that 59% frequently use SVT in legal assessments, but a minority (15%) employ them in clinical assessments. Practice in the UK is only moderately different to that in North America with respect to frequency of use of SVT, although methods employed showed greater diversity. Favored tests, respondents’ justifications for use of SVT and rationales for not using SVT are reported. 相似文献
108.
Research confirming the detrimental impact poor ambient air quality and episodes of abnormally high pollutants has on public health, plus differential susceptibility, calls for improved understanding of this complex topic among all walks of society. The public and particularly, vulnerable groups, should be aware of their quality of air, enabling action to be taken in the event of increased pollution. Policy makers must have a sound awareness of current air quality and future trends, to identify issues, guide policies and monitor their effectiveness. These attitudes are dependent upon air pollution monitoring, forecasting and reporting, serving all interested parties. Apart from the underlying national regulatory obligation a country has in reporting air quality information, data output serves several purposes. This review focuses on provision of real-time data and advanced warnings of potentially health-damaging events, in the form of national air quality indices and proactive alert services. Some of the challenges associated with designing these systems include technical issues associated with the complexity of air pollution and its science. These include inability to provide precise exposure concentrations or guidance on long-term/cumulative exposures or effects from pollutant combinations. Other issues relate to the degree to which people are aware and positively respond to these services. Looking to the future, mobile devices such as cellular phones, equipped with sensing applications have potential to provide dynamic, temporally and spatially precise exposure measures for the mass population. The ultimate aim should be to empower people to modify behaviour-for example, when to increase medication, the route/mode of transport taken to school or work or the appropriate time to pursue outdoor activities-in a way that protects their health as well as the quality of the air they breathe. 相似文献
109.
110.
The aim of this study was to apply a novel economic tool (cost satisfaction analysis) to assess the utility of fixed prosthodontics, to review its applicability, and to explore the perceived value of treatment. The cost satisfaction analysis employed the validated Patient Satisfaction Questionnaire (PSQ). Patients with a known prostheses outcome over 1-20 years were mailed the PSQ. Five hundred patients (50·7%) responded. Remembered satisfaction at insertion (initial costs) and current satisfaction (costs in hindsight) were reported on VAS, and the difference calculated (costs with time). Percentage and grouped responses (low, <40%; medium, 40-70%; high, > 70%) were analysed in relation to patient gender, age and willingness to have undergone the same treatment again, and in relation to prostheses age, type, complexity and outcome. Significance was set at P = 0·05. Averages were reported as means ± standard error. Satisfaction with initial costs and costs in hindsight were unrelated to patient gender and age, and prostheses age, type and complexity. Patients with a failure and those who would elect to not undergo the same treatment again were significantly less satisfied with initial costs (P = 0·021, P < 0·001) and costs in hindsight (P = 0·021, P < 0·001) than their counterparts. Patient's cost satisfaction (entire cohort) had significantly improved from 53 ± 1% at insertion to 81 ± 0·9% in hindsight (28 ± 1% improvement, P < 0·001). Patient cost satisfaction had also significantly improved, and the magnitude of improvement was the same within every individual cohort (P = 0·004 to P < 0·001), including patients with failures, and those who in hindsight would not undergo the same treatment again. Low satisfaction was reported by 166 patients initially, but 94% of these reported improvements in hindsight. Fourteen patients (3%) remained dissatisfied in hindsight, although 71% of these would still choose to undergo the same treatment again. Cost satisfaction analysis provided an evaluation of the patient's perspective of the value of fixed prosthodontic treatment. Although fixed prosthodontic treatment was perceived by patients to be expensive, it was also perceived to impart value with time. Cost satisfaction analysis provides a clinically useful insight into patient behaviour. 相似文献