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51.
Background: Freezing of gait is a disabling symptom of Parkinson's disease that ultimately affects approximately 80% of patients, yet very little research has focused on predicting the onset of freezing of gait and tracking the longitudinal progression of symptoms prior to its onset. The objective of the current study was to examine longitudinal data spanning the transition period when patients with PD developed freezing of gait to identify symptoms that may precede freezing and create a prediction model that identifies those “at risk” for developing freezing of gait in the year to follow. Methods: Two hundred and twenty‐one patients with PD were divided into 3 groups (88 nonfreezers, 41 transitional freezers, and 92 continuing freezers) based on their responses to the validated Freezing of Gait‐Questionnaire item 3 at baseline and follow‐up. Critical measures across motor, cognitive, mood, and sleep domains were assessed at 2 times approximately 1 year apart. Results: A logistic regression model that included age, disease duration, gait symptoms, motor phenotype, attentional set‐shifting, and mood measures could predict with 70% and 90% accuracy those patients who would and would not develop, respectively, freezing of gait over the next year. Notably, the Freezing of Gait‐Questionnaire total and the anxiety section of the Hospital Anxiety and Depression Scale were the strongest predictors and alone could significantly predict if one might develop freezing of gait in the next 15 months with 82% accuracy. Conclusions: Our results suggest that it is possible to identify the majority of patients who will develop freezing of gait in the following year, potentially allowing targeted interventions to delay or possibly even prevent the onset of freezing. © 2017 International Parkinson and Movement Disorder Society  相似文献   
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Purpose

To define percutaneously accessible, anatomically reproducible swine lymph nodes using magnetic resonance imaging, ultrasound, and ethiodized oil (Lipiodol; Guerbet, Bloomington, Indiana) lymphangiography.

Materials and Methods

Five adult female swine (Yorkshire, 50–60 kg) were used. Under general anesthesia, T1-weighted and T2-weighted, coronal and axial images of the entire swine were obtained. The animal’s extrathoracic, extraperitoneal soft tissues from the neck to the groins were examined with ultrasound. Lymph nodes ≥ 1 cm were marked before the animal was transferred to the angiography suite. Under ultrasound guidance, the nodes were accessed, and lymphangiograms were obtained. The imaging findings between the 3 modalities were correlated, and the lymph node drainage was mapped.

Results

Four lymph nodes/lymph node groups were identified that were reproducible in all 5 animals, > 1 cm and percutaneously accessible: submandibular node, superficial cervical lymph node group, subiliac node, and superficial inguinal lymph node group. Drainage of these nodes mirrored human anatomy. The abdominopelvic lymphatics formed a retroperitoneal cisterna chyli and drained cephalad via a thoracic duct.

Conclusions

The swine exhibits reproducible lymphatic anatomy with at least 4 percutaneously accessible lymph nodes/lymph node groups. Based on these results, the swine may be a suitable large animal model for research into lymphatic interventions.  相似文献   
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To assess the measurement invariance of the Center for Epidemiologic Studies Depression Scale (CES-D) 2 months after delivery in 656 English-speaking immigrant and non-immigrant women who had at least one other child under 16 and who gave birth in one of two urban Canadian centers. We also compared levels of depression in these two groups using this scale. Multiple group confirmatory factor analysis showed that configural, metric and partial scalar invariances were present and allowed for meaningful substantive comparisons to be made between immigrants and non-immigrants using linear and logistic regressions on an invariant 15-item version of the scale. We observed a novel 4-factor structure for the CES-D in postpartum women and established a 15-item version of this scale that was invariant across immigrant and non-immigrant groups. This suggests that women conceptualize postpartum depression (PPD) in similar ways using the 15-item version of this scale and that meaningful substantive comparisons can be made using it. Indeed, immigrants manifested higher levels of depressive symptoms than non-immigrants (unstandardized b = 1.34, p = 0.02) and an increased risk of being a potential case of PPD (OR = 2.16, 95%CI 1.10–4.19), even after adjustment for other risk factors. Immigrant and non-immigrant women appear to conceptualize PPD in similar ways using this 15-item version of the CES-D. Immigrants may develop more depressive symptoms and be at increased risk of developing an episode of PPD.  相似文献   
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This study examined the factor structure of the Repetitive Behavior Scale-Revised (RBS-R) in a sample of 287 preschool-aged children with autism spectrum disorder (ASD). A confirmatory factor analysis was used to examine six competing structural models. Spearman’s rank order correlations were calculated to examine the associations between factor scores and variables of interest. The 3- and 5-factor models were selected as preferable on the basis of fit statistics and parsimony. For both models, the strongest correlations were with problem behavior scores on the Child Behavior Checklist and repetitive behavior scores on the ADI-R. Developmental index standard scores were not correlated with factors in either model. The results confirm the utility of the RBS-R as a measure of repetitive behaviors in young children with ASD.  相似文献   
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Interventional radiology (IR) has been for the last few years undergoing a transformation from a service oriented to a clinically oriented specialty. With increasing oncologic procedures and patient volume, the balance between quality clinical care, and the time constraints on the busy interventionalist pull in opposing forces. The need for greater clinical support staff in the IR practice is unquestionable. Physician Assistants (and other Physician Extenders) have been in the medical field since the 1960s with intensive clinical training, capabilities of providing patient care and ability to generate revenue income more than justifies their place in the IR. The contemporary model of a clinical orientated service within IR for cancer patients undergoing interventional oncology procedures should include Physician Extenders as a vital part of the team allowing delivery of high-quality patient care.  相似文献   
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OBJECTIVE: The purpose of this study was to assess the utility of assessment of tumor size and enhancement with diffusion-weighted and conventional MRI in the evaluation of response to transarterial chemoembolization therapy for metastatic ocular melanoma. CONCLUSION: In patients with ocular melanoma and liver metastasis treated with transarterial chemoembolization, functional MRI showed significant changes in the lesions. These changes included a decrease in tumor enhancement and an increase in the apparent diffusion coefficient of the tumor, suggesting increasing tumor necrosis and cell death.  相似文献   
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PURPOSE: To assess the value of functional magnetic resonance (MR) imaging in the evaluation of early tumor response after transarterial chemoembolization (TACE) for metastatic leiomyosarcoma and compare tumor response using functional MR imaging versus traditional imaging response assessment, which is based on tumor size. MATERIALS AND METHODS: We evaluated 31 lesions in 10 patients with liver metastases from leiomyosarcoma using MR imaging studies before and after TACE. Diffusion and contrast-enhanced MR imaging was performed on a 1.5-T unit. Imaging protocol consisted of T2-weighted fast spin-echo images, breath-hold diffusion-weighted echo-planar images, and breath-hold unenhanced and contrast-enhanced T1-weighted 3-dimensional fat-suppressed spoiled gradient-echo images in the arterial phase (20 seconds) and portal venous phase (60 seconds). Parameters evaluated included change in tumor size, enhancement, and apparent diffusion coefficient (ADC) values. Median survival was also calculated for the entire cohort. RESULTS: The 31 lesions evaluated had a mean size of 4.8 cm before treatment. Tumor size decreased only by 2% immediately after treatment. Decrease of tumor enhancement after treatment was significant (P < 0.0001) in the arterial phase (69%) as well as in the portal venous phase (64%). After TACE, mean tumor ADC increased by 20% (P = 0.0015), whereas mean nontreated liver, spleen, and muscle ADC values did not change significantly (P = 0.44, P = 0.287, and P = 0.098, respectively). Patient survival from time of first TACE was 21 months for the entire cohort. CONCLUSION: In patients with leiomyosarcoma and liver metastases who were treated with TACE, significant early changes in the treated lesions occurred on functional MR imaging. These include decrease in tumor enhancement and increase in tumor ADC value, suggesting increasing tumor necrosis and cell death. Changes in tumor size were small and inadequate to assess treatment response, suggesting limitation of the current response criteria in the early assessment of tumor response.  相似文献   
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