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The purpose of this study was to retrospectively assess the effect of a postprocessing nonlinear three-dimensional optimized reconstruction algorithm on image quality and lesion characteristics in abdominal and pelvic computed tomographic (CT) images. Institutional review board approved the HIPAA-compliant study protocol; informed consent was waived. Abdominal and pelvic CT images (40 patients; male-female ratio, 20:20; age range, 28-86 years) at 5-mm (n = 20) and 2-mm (n = 20) section thicknesses were postprocessed with the algorithm at three noise reduction levels. Image noise at the level of porta hepatis and acetabulum was evaluated with a five-point scale (1, no or minimal noise; 5, unacceptable noise), and presence and number of lesions and conspicuity were assessed. Statistical analysis was performed (Wilcoxon signed rank test, analysis of variance). Significant noise reduction was noted at all three levels with the algorithm (P < .05). Reduction in image contrast was noted with only one noise reduction level (P < .0001). The algorithm improves image noise without affecting lesion conspicuity and detection on low-dose abdominal and pelvic CT images.  相似文献   
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Opinion statement Treatment and cure of salivary gland neoplasms requires surgical intervention in most cases. For parotid neoplasms, the most common surgical procedure performed is the superficial parotidectomy with facial nerve preservation. Postoperative radiation therapy is indicated in high-grade salivary gland malignancies and malignancies with increased risk of locoregional recurrence. Primary radiation, including neutron beam techniques, may play a role in certain histologic types or nonoperative candidates. Chemotherapy has yet to result in improvements in survival or quality of life in the treatment of salivary gland malignancy. Advances in radiation therapy techniques, including intensity-modulated radiation therapy, provide opportunities for reduced morbidity.  相似文献   
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The synthesis of a series of some novel Schiff base complexes of Cu(II), Ni(II), Co(II), Mn(II), Zn(II) with a tetradentate Schiff base has been achieved by the reaction of malonyl hydrazide with dehydroacetic acid in ethanol under refluxing condition. All the synthesized metal complexes and ligand were characterized on the basis of elemental analysis, UV–Visible, 1H and 13C NMR, IR spectroscopy and mass spectrometry. The IR spectral data suggest that azomethine N and enolic O atom are involved in coordination with metal ions, and the ligand behaves as a tetradentate ligand with ONNO donor atoms. The mass spectrum of the complexes reveals the formation of metal ligand bonding in stoichiometric ratio 1:1 (M:L). The UV–Visible data suggest the square planner geometry for the synthesized complexes. All compounds were screened for their antibacterial activity against gram-positive and gram-negative bacteria using Ampicillin as a standard drug. It has been found that metal complexes show enhanced activity as compared to ligand, and some modification in ligand structure may lead to better antibacterial agents in future.  相似文献   
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Background In Australia, certain pharmacies have undertaken a role in the management of the chronic sleep disorder, obstructive sleep apnea. The perspectives of pharmacy staff involved in this niche clinical service have never been formally collated on a national scale. The experiences of Australian pharmacies could provide a template for pharmacies in other health systems to adopt similar roles. Objective To provide an overview of the perspectives of pharmacy staff involved in Continuous Positive Airway Pressure (CPAP) and sleep apnea-related services. Specifically, to describe clinical and structural elements, explore benefits and barriers, investigate viability, and gauge perspectives on future directions. Setting Australian community pharmacies involved in CPAP and sleep apnea-related services. Method Cross-sectional mail survey. A questionnaire designed to meet the study objectives was developed by the researchers and mailed to all pharmacies in Australia providing CPAP services during the period of study recruitment. Pharmacies were identified through the distributor lists of the major CPAP manufacturers and a comprehensive Internet search. Non-responders were contacted in two subsequent recruitment rounds. Main outcome measure Self-reported sleep apnea service specifics. Results A response rate of 55 % was achieved (n = 106 questionnaires valid for data entry). Benefits of providing a CPAP service included meeting patient and community needs, and professional satisfaction. Barriers included the cost of CPAP equipment to patients and lack of time. A majority of pharmacies (71 %) reported the service was financially viable despite most (63 %) not charging a ‘fee for service.’ Respondents expressed the view that CPAP provision should remain a specialist area of practice within the pharmacy profession. Key areas identified for improvement within the service were: (1) Staff training and knowledge (2) Promotion of the service and increasing public awareness (3) Infrastructure and expansion (4) Inter-professional collaboration and communication (5) Patient follow-up. Conclusion The provision of CPAP and sleep apnea-related services can be a viable and rewarding experience for pharmacists. The role may need to remain a specialised area for those willing to invest significantly in the service—in time, staff, resources and finances.  相似文献   
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