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41.
Olmsted  WW; McGee  TP 《Radiology》1977,123(3):661-666
Most central nervous system aneurysms occur around the circle of Willis, and are congenital or arteriosclerotic in origin when in that location. Peripherally located aneurysms are either idiopathic or secondary to infection, tumor embolus (from choriocarcinoma and cardiac myxoma), Moyamoya disease, or trauma. The pathophysiologic features of these aneurysms are discussed.  相似文献   
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Purpose:To present clinical profile and risk factors of sight-threatening diabetic retinopathy (STDR) among people with age of onset of diabetes (AOD) <25 versus ≥25 years.Methods:A retrospective chart analysis of consecutive patients with diabetic retinopathy (DR) n = 654) treated at 14 eye care centers across India between 2018 and 2019 was performed. Patients were divided into two groups, Group 1: AOD <25 years and Group 2: AOD ≥25 years. DR and diabetic macular edema (DME) were classified using the International Clinical Classification of DR severity scale. STDR included severe nonproliferative DR (NPDR), proliferative DR (PDR), and moderate to severe DME. A multilevel mixed-effects model was used for comparison between two groups: 1) Patients with DR and AOD <25 years and 2) Patients with DR and AOD ≥25 years. Bivariate and multivariate regression analyses were used to evaluate risk factors between the two groups.Results:A total of 654 patients were included, 161 (307 eyes) in AOD <25 and 493 (927 eyes) in AOD >25 group. There was a higher prevalence of PDR with high-risk characteristics in AOD <25 group (24% vs. 12%) at baseline and 12-month follow-up (25% vs. 6%); P < 0.001. Systolic hypertension and poor glycemic control were risk factors in both groups, with no difference in these modifiable risk factors between groups.Conclusion:People with youth-onset DM are likely to present with severer form of STDR despite similar modifiable risk factors. Therefore, strict control of systolic blood pressure, glycemic status, and regular screening for DR are recommended to reduce the risk of STDR irrespective of the age of onset of diabetes.  相似文献   
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Radiotherapy utilization rates in rural Australia are suboptimal, with one solution being the building of single machine units (SMUs). One concern raised with such an approach is the quality of care delivered in SMUs. The Australian and Victorian governments have established two SMUs in the state of Victoria, with each SMU operated as a satellite service of a major ‘hub’ site. We report on the planned evaluation of practice quality. Radiation oncologist (RO) clinical practice was externally audited using the Royal Australian and New Zealand College of Radiologists Peer Review Audit instrument. This tool splits RO clinical practice into documentation/quality assurance (QA) criteria and decision‐making criteria. Over the four sites, 130 patients were randomly selected for audit. At hub sites, 79.6% of all criteria audited were adequate, compared with 84.4% of criteria audited at SMUs (P = 0.0002). This difference was largely because of better adherence to documentation/QA criteria at the SMU sites. RO decision‐making and protocol adherence were routinely very high and consistent with other clinical practice audits. There were no significant differences between hubs and SMUs for adherence to decision‐making criteria; however, the few potential deficiencies in patient care identified occurred only at the hub sites. In at least one of these cases, potential suboptimal management was as a direct result of inadequate documentation. This audit found that SMUs provide as high a standard of radiotherapeutic care as larger hub departments. The findings also emphasize the need for all departments to target clinical documentation.  相似文献   
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Removal of mixed pesticides, namely alachlor, metolachlor, chlorpyriphos, fipronil, α-endosulfan, β-endosulfan, p,p′-DDT and two metabolites p,p′-DDE and endosulfan sulphate from aqueous solution by batch adsorption onto three commercial organo-modified montmorillonite clays [modified with octadecylamine (ODA-M), modified with dimethyl- dialkylamine (DMDA-M) and modified with octadecylamine and aminopropyltriethoxysilane (ODAAPS-M)] were investigated. Effect of process variables, mainly contact time and initial concentration of mixed pesticides, on adsorption phenomenon were evaluated. To understand the adsorption kinetic pseudo-first-order and pseudo-second-order models were tested. The pseudo-second-order model provided the best fit for explaining adsorption kinetics, on the basis of high correlation coefficient (r) and normalized percent deviation values. The adsorption equilibrium was explained by the Freundlich isotherm (r = 0.951–0.992). High values (0.17–0.52 mg g?1) of Freundlich constant (Kf) indicated higher affinity of pesticides towards all three organoclays, as a result of hydrophobic interaction between the adsorbent/adsorbate systems. Pesticides with high octanol–water partition coefficient (Kow) and low water solubility showed faster adsorption with higher Kf values as compared to the pesticides with low Kow and high water solubility. The order of organoclays for removal efficiency of mixed pesticide was ODAAPS-M > DMDA-M > ODA-M. These findings may find application to decontaminate or treat mixed pesticide contaminated industrial/agricultural waste waters.  相似文献   
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