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991.

Purpose

To evaluate a novel magnetic resonance (MR) angiography (MRA) of three‐dimensional (3D) MR digital subtraction angiography (MRDSA) without contrast material, which is essentially 3D true steady‐state free precession (SSFP) with selected inversion recovery (IR) pulse using multiple cardiac phase acquisitions with a short increment delay in the assessment of normal cranial arteries, as a feasibility study before clinical use.

Materials and Methods

Serial MRA images using 3D MRDSA without contrast material were acquired from 10 healthy volunteers. Visualization of normal cranial arteries with time‐spatial labeling inversion pulse (Time‐SLIP) MRDSA was qualitatively compared with the conventional MRA method, 3D time‐of‐flight (TOF)‐MRA.

Results

In all volunteers, serial 3D MRDSAs containing hemodynamic information were successfully imaged. The results of visualization of the branches of the cranial arteries with Time‐SLIP MRDSA were comparable to those of 3D TOF‐MRA. The mean scores ± standard deviations for normal cerebral arteries (internal carotid arteries, middle cerebral arteries, anterior cerebral arteries, posterior cerebral arteries, and basilar arteries) were 2.4 ± 0.5, 2.3 ± 0.5, 2.0 ± 0.7, 2.3 ± 0.7, and 2.5 ± 0.7, respectively.

Conclusion

Time‐SLIP 3D MRDSA is a simple method for obtaining hemodynamic information. Although more MR sequence improvement is needed, it can play an important role in assessing cranial arteries without contrast material. J. Magn. Reson. Imaging 2009;30:214–218. © 2009 Wiley‐Liss, Inc.  相似文献   
992.
Integration of color information in 3D models acquired with a topometric measurement system opens a wide field of applications in medicine, e.g. prosthetics. To ensure an accurate and reliable color reproduction in a 3D topometric measurement system, different approaches have been evaluated. These techniques focus on the calibration of the CCD camera using color test charts by applying a polynomial regression method as well as numerical methods to compensate an intensity decay of the illumination in 3D datasets which is caused by varying distances and orientations of the measured object with respect to the light source. The methods presented in this contribution have been applied to a topometric measurement system with one-chip color CCD cameras. An enhanced color reproduction of various objects is demonstrated.  相似文献   
993.

Purpose:

To evaluate the effect of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd‐EOB‐DTPA) on T2‐weighted imaging (T2WI) and diffusion‐weighted imaging (DWI) for the diagnosis of hepatocellular carcinoma (HCC).

Materials and Methods:

The phantom signal intensity was measured. We also evaluated 72 patients including 30 patients with HCC. T2WI and DWI were obtained before and then 4 and 20 min after injecting the contrast medium. The signal to noise ratio (SNR), contrast to noise ratio (CNR), and apparent diffusion coefficient (ADC) were calculated in the tumor and liver parenchyma.

Results:

The phantom signal intensity increased on T2WI at a concentration of contrast medium less than 0.2 mmol/L but decreased when the concentration exceeded 0.4 mmol/L. SNR of the liver parenchyma on T2WI was significantly different between before and 4 min after injecting the contrast medium, while there were no significant differences between before and 4 and 20 min after injection. On T2WI, SNR, and CNR of HCC showed no significant differences at any time. SNR, CNR, and ADC of the liver parenchyma and tumor on DWI also showed no significant differences at any time.

Conclusion:

It is acceptable to perform T2WI and DWI after injection of Gd‐EOB‐DTPA for the diagnosis of HCC. J. Magn. Reson. Imaging 2010;32:229–234. © 2010 Wiley‐Liss, Inc.  相似文献   
994.
Introduction: Amyotrophic lateral sclerosis (ALS) patients benefit from multidisciplinary care in an ALS clinic. We studied whether multidisciplinary care of ALS patients using the store and forward method of telemedicine was feasible and acceptable to patients and providers. Methods: ALS patients seen in the University of Florida (UF) Jacksonville ALS clinic were eligible for our study. A trained telemedicine nurse performed and recorded a multidisciplinary assessment of the patient in their home. Clinic team members reviewed the assessments and provided recommendations, and the clinic director discussed the plan with the patient via videoconference. Patient and provider satisfaction was evaluated using surveys. Results: Eighteen patients completed a total of 27 telemedicine visits. Patient satisfaction was excellent and provider satisfaction was very good. Discussion: The store and forward method of telemedicine is an acceptable alternative to live telemedicine for the multidisciplinary care of ALS patients. This method of care may improve access to multidisciplinary care for this patient population. Muscle Nerve 59 :34–39, 2019  相似文献   
995.
Respiratory symptoms elicited by perfume are common in the population but have unclear pathophysiology. Increased capsaicin cough responsiveness has been associated with the symptoms, but it is unknown whether the site of the symptoms in the airways influences this association. The aim of this study was to investigate the association between the site of airway symptoms elicited by perfume and cough responsiveness to bronchial challenge with capsaicin. 21 eczema patients with respiratory symptoms elicited by perfume were compared with 21 healthy volunteers in a sex- and age-matched case control study. The participants completed a symptom questionnaire and underwent a bronchial challenge with capsaicin. Lower, but not upper, respiratory symptoms elicited by perfume were associated with increased capsaicin cough responsiveness. Having severe symptoms to perfume (n=11) did not relate to the site of the symptoms in the airways and was not associated with increased capsaicin cough responsiveness. In conclusion, respiratory symptoms elicited by perfume may reflect local hyperreactivity related to defensive reflexes in the airways, and measurements of the capsaicin cough reflex are relevant when patients with lower respiratory symptoms related to environmental perfume exposures are investigated.  相似文献   
996.
Despite recent studies confirming task shifting is both safe and effective, its implementation has proven difficult in practice. So too in the Netherlands, where legal barriers enforcing strict professional boundaries have historically limited task shifting. In recent years, Dutch policymakers have experimented with temporary expanded scopes of practice (ESP) for several professional groups, with the aim to facilitate task shifting in order to increase the overall effectiveness and efficiency of health care. The Clinical Technologist (CT), is an emerging new professional group that has received such a temporary ESP pending an evaluation. This paper reports the qualitative findings of the implementation process of providing CTs with an temporary ESP. Data collection consisted of 69 semi-structured interviews, 3 focus group interviews and 9 participant observations, conducted between September 2015 and October 2017. Analysis was conducted through an ‘editing analysis style’ whereby data were categorized using the conceptual framework of Grol & Wensing’s implementation model. The study suggests that social features are of great importance when implementing task shifting. In situations with few social barriers, organizational and administrative barriers seem to be less dominant, thereby expediting the overall implementation process. Consequently, we recommend that policymakers should prioritize social features over organizational features when implementing task shifting.  相似文献   
997.
998.
999.
We sought to investigate the type and kinetics of late-phase nasal inflammatory response after nasal challenge with occupational allergens. Participants were 10 subjects experiencing work-related rhinitis symptoms who underwent specific inhalation challenge and tested positive for occupational rhinitis. During challenge, we monitored changes in inflammatory cells, eosinophil cationic protein, myeloperoxidase, and interleukin-8 in nasal lavage samples. The challenge with the active agent induced a significant increase in the percentage of eosinophils at 30 minutes as compared with prechallenge values (P = 0.04). A significant increase in eosinophil cationic protein levels after challenge with the control (P = 0.01) and active agent (P = 0.02) was observed in the late phase after challenge. No significant changes in nasal levels of neutrophils, myeloperoxidase, and interleukin-8 were observed on both control and active challenge days. Our results suggest a predominant nasal eosinophilic inflammatory response after occupational allergen challenge.  相似文献   
1000.

Objectives

Differences between country-specific guidelines for economic evaluations complicate the execution of international economic evaluations. The aim of this study was to develop cross-European recommendations for the identification, measurement and valuation of resource use and lost productivity in economic evaluations using a Delphi procedure.

Methods

A comprehensive literature search was conducted to identify European guidelines on the execution of economic evaluations or costing studies as part of economic evaluations. Guideline recommendations were extracted by two independent reviewers and formed the basis for the first round of the Delphi study, which was conducted among European health economic experts. During three written rounds, consensus (agreement of 67% or higher) was sought on items concerning the identification, measurement and valuation of costs.

Results

Recommendations from 18 guidelines were extracted. Consensus among 26 panellists from 17 European countries was reached on 61 of 68 items. The recommendations from the Delphi study are to adopt a societal perspective, to use patient report for measuring resource use and lost productivity, to value both constructs with use of country-specific standardized/unit costs and to use country-specific discounting rates.

Conclusion

This study provides consensus-based cross-European recommendations on how to measure and value resource use and lost productivity in economic evaluations. These recommendations are expected to support researchers, healthcare professionals, and policymakers in executing and appraising economic evaluations performed in international contexts.
  相似文献   
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