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891.
892.
BACKGROUND: Two cases of hepatitis A among persons exposed to the same lot of solvent/detergent-treated antihemophilic factor VIII concentrate were reported to a surveillance system. An investigation was conducted to find additional cases and determine the source of infection. STUDY DESIGN AND METHODS: A seroprevalence study was conducted among persons with exposure to the suspect lot for serologic evidence of recent infection with hepatitis A virus (HAV). RESULTS: Six cases of recent HAV infection were discovered: four of the patients had been infused with material from the suspect lot of factor VIII, and two had received infusions of factor IX concentrate made from plasma pools common to the suspect factor VIII lot. HAV was identified in one of the plasma pools, in the factor VIII product, and in serum or stool from two factor VIII recipients and one factor IX recipient. The genetics sequence of the virus in the plasma pool, the factor VIII lot, and the factor VIII recipients were identical, while that of the virus in the factor IX recipient differed by a single base. CONCLUSION: These data document the transmission of HAV by a factor VIII concentrate and implicate factor IX products manufactured from a common source-plasma pool.  相似文献   
893.

Background

Systematic planning could improve the generally moderate effectiveness of interventions to enhance adherence to clinical practice guidelines. The aim of our study was to demonstrate how the process of Intervention Mapping was used to develop an intervention to address the lack of adherence to the national CPG for low back pain by Dutch physical therapists.

Methods

We systematically developed a program to improve adherence to the Dutch physical therapy guidelines for low back pain. Based on multi-method formative research, we formulated program and change objectives. Selected theory-based methods of change and practical applications were combined into an intervention program. Implementation and evaluation plans were developed.

Results

Formative research revealed influential determinants for physical therapists and practice quality managers. Self-regulation was appropriate because both the physical therapists and the practice managers needed to monitor current practice and make and implement plans for change. The program stimulated interaction between practice levels by emphasizing collective goal setting. It combined practical applications, such as knowledge transfer and discussion-and-feedback, based on theory-based methods, such as consciousness raising and active learning. The implementation plan incorporated the wider environment. The evaluation plan included an effect and process evaluation.

Conclusions

Intervention Mapping is a useful framework for formative data in program planning in the field of clinical guideline implementation. However, a decision aid to select determinants of guideline adherence identified in the formative research to analyse the problem may increase the efficiency of the application of the Intervention Mapping process.  相似文献   
894.
895.
We present a case of de novo polymorphous low-grade adenocarcinoma (PLGA) arising in a minor salivary gland with a relatively large radiographic extent compared with that of most of the PLGAs reported. This paper describes the radiographic extent of the lesion and the findings of CT imaging.  相似文献   
896.
BACKGROUND: Treatment of bullous pemphigoid (BP) with systemic immunosuppressive agents, in particular with systemic corticosteroids, has many long-term side-effects. A dozen reports were published regarding the efficacy of topical corticosteroids in the treatment of bullous pemphigoid. OBJECTIVE: To evaluate the efficacy of potent class I topical corticosteroids in relation to the affected body surface area (BSA) in patients with bullous pemphigoid and to review the literature. METHODS: An open prospective trial with 10 patients with BP with measurement of the affected BSA. Treatment protocol consisted of three steps: potent class I topical corticosteroid treatment, systemic tetracyclines and systemic corticosteroids. Follow-up period was between 24 and 72 months. RESULTS: Our study suggests a correlation between the success rate of topical corticosteroid treatment and the body surface area initially affected: all patients with an affected BSA of less than 20% healed with topical treatment only. The patients with more than 40% affected BSA needed systemic treatment with steroids. CONCLUSION: Topical class I corticosteroids seem to be effective in healing lesions of BP, especially if less than 20% of the BSA is affected. This study comprises only 10 patients, making further studies necessary to draw definite conclusions.  相似文献   
897.

Background

Accelerometers have been used to determine the amount of time that children spend sedentary. However, as time spent sitting may be detrimental to health, research is needed to examine whether accelerometer sedentary cut-points reflect the amount of time children spend sitting. The aim of this study was to: a) examine agreement between ActiGraph (AG) cut-points for sedentary time and objectively-assessed periods of free-living sitting and sitting plus standing time using the activPAL (aP); and b) identify cut-points to determine time spent sitting and sitting plus standing.

Methods

Forty-eight children (54% boys) aged 8-12 years wore a waist-mounted AG and thigh-mounted aP for two consecutive school days (9-3:30 pm). AG data were analyzed using 17 cut-points between 50-850 counts·min-1 in 50 counts·min-1 increments to determine sedentary time during class-time, break time and school hours. Sitting and sitting plus standing time were obtained from the aP for these periods. Limits of agreement were computed to evaluate bias between AG50 to AG850 sedentary time and sitting and sitting plus standing time. Receiver Operator Characteristic (ROC) analyses identified AG cut-points that maximized sensitivity and specificity for sitting and sitting plus standing time.

Results

The smallest mean bias between aP sitting time and AG sedentary time was AG150 for class time (3.8 minutes), AG50 for break time (-0.8 minutes), and AG100 for school hours (-5.2 minutes). For sitting plus standing time, the smallest bias was observed for AG850. ROC analyses revealed an optimal cut-point of 96 counts·min-1 (AUC = 0.75) for sitting time, which had acceptable sensitivity (71.7%) and specificity (67.8%). No optimal cut-point was obtained for sitting plus standing (AUC = 0.51).

Conclusions

Estimates of free-living sitting time in children during school hours can be obtained using an AG cut-point of 100 counts·min-1. Higher sedentary cut-points may capture both sitting and standing time.  相似文献   
898.

Introduction

Radiofrequency ablation (RFA) and percutaneous vertebroplasty (PVP) are used independently and in combination to treat metastatically involved vertebrae with the aim of relieving pain, reducing tumour burden and providing bony mechanical stabilization.

Purpose

The aim of this work was to characterize the effect of two bone-targeted RFA devices, alone and in combination with PVP, to improve strength and mechanical stability in vertebrae with osteolytic metastatic disease.

Methods

Simulated spinal metastases (n = 12) were treated with one of two bone-targeted RFA devices (bipolar cooled or bone coil RF electrodes), followed by PVP. Under axial compressive loading, spinal canal narrowing was measured in the intact specimen, after tumour simulation, post-RFA and post-PVP.

Results

RFA alone resulted in successful tumour shrinkage and cavitation, but further increased canal narrowing under loading. RFA combined with PVP significantly reduced posterior wall stability in samples where sufficient tumour shrinkage and cavitation were coupled with a pattern of cement deposition which extended to posterior vertebral body.

Conclusions

RFA combined with cement deposition in the posterior vertebral body demonstrates significantly more stable vertebrae under axial loading.
  相似文献   
899.

Background and Objectives

Bacterial pneumonia still contributes to morbidity/mortality in HIV infection despite effective combination antiretroviral therapy (cART). Evaluation of Subcutaneous Interleukin‐2 in a Randomized International Trial (ESPRIT), a trial of intermittent recombinant interleukin‐2 (rIL‐2) with cART vs. cART alone (control arm) in HIV‐infected adults with CD4 counts ≥300 cells/μL, offered the opportunity to explore associations between bacterial pneumonia and rIL‐2, a cytokine that increases the risk of some bacterial infections.

Methods

Baseline and time‐updated factors associated with first‐episode pneumonia on study were analysed using multivariate proportional hazards regression models. Information on smoking/pneumococcal vaccination history was not collected.

Results

IL‐2 cycling was most intense in years 1–2. Over ≈7 years, 93 IL‐2 [rate 0.67/100 person‐years (PY)] and 86 control (rate 0.63/100 PY) patients experienced a pneumonia event [hazard ratio (HR) 1.06; 95% confidence interval (CI) 0.79, 1.42; P=0.68]. Median CD4 counts prior to pneumonia were 570 cells/μL (IL‐2 arm) and 463 cells/μL (control arm). Baseline risks for bacterial pneumonia included older age, injecting drug use, detectable HIV viral load (VL) and previous recurrent pneumonia; Asian ethnicity was associated with decreased risk. Higher proximal VL (HR for 1 log10 higher VL 1.28; 95% CI 1.11, 1.47; P<0.001) was associated with increased risk; higher CD4 count prior to the event (HR per 100 cells/μL higher 0.94; 95% CI 0.89, 1.0; P=0.04) decreased risk. Compared with controls, the hazard for a pneumonia event was higher if rIL‐2 was received <180 days previously (HR 1.66; 95% CI 1.07, 2.60; P=0.02) vs.≥180 days previously (HR 0.98; 95% CI 0.70, 1.37; P=0.9). Compared with the control group, pneumonia risk in the IL‐2 arm decreased over time, with HRs of 1.41, 1.71, 1.16, 0.62 and 0.84 in years 1, 2, 3–4, 5–6 and 7, respectively.

Conclusions

Bacterial pneumonia rates in cART‐treated adults with moderate immunodeficiency are high. The mechanism of the association between bacterial pneumonia and recent IL‐2 receipt and/or detectable HIV viraemia warrants further exploration.  相似文献   
900.
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