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61.
Head movement presents a continuing problem in PET studies. Head restraint minimizes movement but is unreliable, resulting in the need to develop alternative strategies. These include frame-by-frame (FBF) realignment or use of motion tracking (MT) during the scan to realign PET acquisition data. Here we present a comparative analysis of these 2 methods of motion correction. METHODS: Eight volunteers were examined at rest using (11)C-raclopride PET with the radioligand administered as a bolus followed by constant infusion to achieve steady state. Binding potential (BP) was estimated using the ratio method during 2 periods of the scan at steady state. Head movement was compensated by using coregistration between frames (FBF) and 3 methods using MT measurements of head position acquired with a commercially available optical tracking system. RESULTS: All methods of realignment improved test-retest reliability and noise characteristics of the raw data, with important consequences for the power to detect small changes in radiotracer binding, and the potential to reduce false-positive and false-negative results. MT methods were superior to FBF realignment using coregistration on some indices. CONCLUSION: Such methods have considerable potential to improve the reliability of PET data with important implications for the numbers of volunteers required to test hypotheses.  相似文献   
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A 62-year-old male with no significant medical history developed thromboembolic complications in the lower limbs shortly after an assault which involved punching and kicking to the trunk. Laparotomy revealed intra-abdominal injuries and an abdominal aortic aneurysm. Death from multi-organ failure and sepsis occurred 9 days post-injury. The discussion concentrates on blunt force trauma to the abdominal aorta, specifically on causation, mechanisms of injury and complications.  相似文献   
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We followed all consecutive hip fracture patients admitted between 2004 and 2006, identified cases in which the intention was to treat non-operative and compared their functional outcome and mortality with a similar cohort treated surgically over the same period. We recorded length of hospital stay, place of discharge, pre and post-fracture mobility and residence, 30 days and 1 year mortality, re-admission due to same fracture and delayed surgery. The group treated surgically was recruited and matched for age, gender, pre and post-fracture mobility, mental confusion and independence. 25 patients were treated non-operative. 22 patients treated surgically over the same time period matched the patient characteristics of the non-operative arm. The mean hospital stay was 13 days in both groups. There were 4 extra-capsular fractures (3 displaced) and 21 intra-capsular fractures (5 displaced) in the non-operative arm and 11 extra-capsular fractures and 9 intra-capsular fractures in the surgically treated arm. 4 patients from the non-operative treatment group underwent late surgery because of persisting hip pain 20 days-2 months after the index event (2 cannulated screws, 1 hemiarthroplasty, 1 total hip arthroplasty). 11 patients in the surgical treatment arm underwent dynamic screw fixation, 1 had cannulated screw, 1 had total hip replacement and 7 had hemiarthroplasty. 14 of the non-operative treated patients were mobile independently or with aid before fracture but only 9 patients retained their pre-fracture mobility following treatment, compared to 16 patients pre-fracture and 11 patients post-fracture after surgery. 16 patients treated non-operative were living independently prior to injury but only 7 went back to their own residence. Of the operatively treated patients 14 patients were living independently and 10 patients went back to their previous residence. 1 month and 1 year mortality in the non-operative treated group was 4/21 and 7/21 respectively compared to 1/20 and 5/20 in the operative fixation group. There was no statistically significant difference in mobility, residence or mortality between the two groups (Fisher exact test, p > 0.05). Non-operative management after hip fracture is suitable for medically unfit patients and does not result in statistically significant difference in functional outcome or mortality compared to patients treated surgically.  相似文献   
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The objective of this systematic review was to evaluate the impact of pharmacist delivered community-based services to optimise the use of medications for mental illness. Twenty-two controlled (randomised and non-randomised) studies of pharmacists' interventions in community and residential aged care settings identified in international scientific literature were included for review. Papers were assessed for study design, service recipient, country of origin, intervention type, number of participating pharmacists, methodological quality and outcome measurement. Three studies showed that pharmacists' medication counselling and treatment monitoring can improve adherence to antidepressant medications among those commencing treatment when calculated using an intention-to-treat analysis. Four trials demonstrated that pharmacist conducted medication reviews may reduce the number of potentially inappropriate medications prescribed to those at high risk of medication misadventure. The results of this review provide some evidence that pharmacists can contribute to optimising the use of medications for mental illness in the community setting. However, more well designed studies are needed to assess the impact of pharmacists as members of community mental health teams and as providers of comprehensive medicines information to people with schizophrenia and bipolar disorder  相似文献   
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Background: The Rhinitis Symptom Utility Index (RSUI), originally developed in the United States, consists of a patient-preference weighting scheme and a 10-item questionnaire measuring the severity and frequency of rhinitis related symptoms over a 14-day period. This study aimed to determine whether the Chinese RSUI could adopt the US-based multi-attribute utility function (MAUF) in scoring rhinitis symptoms. Methods: In a Hong Kong study, 116 Chinese adults with allergic rhinitis completed the RSUI questionnaire and 36-item Short-Form Health Survey (SF-36) after they had been seen by two otorhinolaryngologists for disease-severity ratings. Respondents then completed computer-administered direct preference measures, i.e., visual analogue scale (VAS) and standard gamble (SG) assessments. The VAS and SG data were used to estimate a MAUF for the Chinese-based RSUI. Results: The derived MAUF was somewhat different than the one developed for the US RSUI. Test–retest reliability for the Chinese RSUI was satisfactory (ICC = 0.71, p<0.001). Scores differentiated among cases with mild, moderate, and severe symptoms (p<0.001); and between those who did and did not require medications to control symptoms (p = 0.031). Findings were significantly correlated with SF-36 domain scores (r = 0.19 to 0.37; p=0.041 to <0.001). When the US-based scoring function was applied to the Chinese subjects, the resulting mean RSUI score was significantly lower (p<0.001). Comparisons between directly measured VAS and SG scores between the US and Chinese samples, demonstrated significant differences (all p<0.05), with the US subjects consistently rating rhinitis symptoms as worse than Chinese subjects. Conclusions: The Chinese RSUI has good measurement properties that reflect patient preferences from the Chinese. Results suggest that there are differences in preference rating between US and Chinese subjects and that use of the US-based preference function for the RSUI would bias the measurement of rhinitis symptom outcomes in Chinese subjects.  相似文献   
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The Enhancing Patient Prenatal Education study tested the feasibility and educational impact of an interactive program for patient prenatal genetic screening and testing education. Patients at two private practices and one public health clinic participated (N = 207). The program collected knowledge and measures of anxiety before and after use of the tool. Time in various prenatal visit activities was collected prior to and after the introduction of the education tool. Providers completed an assessment of their experiences with patients who had used the program. Results indicate that patient knowledge significantly increased from pre to post (p = .0001) with no increase in anxiety (p = .31). Time in clinic activities, including overall visit time, increased. A majority of providers indicated that the program disrupted clinic flow. This assessment suggests that the program increases patient knowledge and does not increase patient anxiety. However, challenges remain to using this program in a clinic setting.  相似文献   
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