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PURPOSE: To affirm the effectiveness and complication rate of postoperative single-dose beta-irradiation (RT) with (90)Sr in the case of primary pterygium in a clinical trial. Pterygium is a benign disease of the supporting orbital tissue that can cause impairment of visual function. Depending on the technique used for surgery, recurrence is described in up to 70% of cases-a reason to combine the initial treatment with radiotherapy or chemotherapy. METHODS AND MATERIALS: This trial was designed as a prospective, randomized, multicenter, double-blind study. Surgery was performed in all cases according to the bare sclera technique. Ninety-one patients with 96 pterygia were postoperatively randomized to either beta-RT or sham RT. In the case of beta-RT, a (90)Sr eye applicator was used to deliver 2500 cGy to the sclera surface at a dose rate of between 200 and 250 cGy/min. Sham RT was given using the same type of applicator without the (90)Sr layer. After treatment, both an ophthalmologist and a radiation oncologist performed the follow-up examinations. The accumulated data were analyzed using a group sequential test. RESULTS: Between February 1998 and September 2002, 96 eyes with primary pterygium were operated on according to the trial protocol. Additional treatment was performed within 24 hours postoperatively. Ten patients were lost to follow-up, resulting in 86 patients who could be analyzed. In the 44 eyes randomized to receive beta-RT, 3 relapses occurred compared with 28 recurrences in the 42 eyes that received sham RT, for a crude control rate of 93.2% vs. 33.3%, respectively. At a mean follow-up of 18 months, major treatment complications had not been observed. CONCLUSION: Single-dose beta-RT after bare sclera surgery is a simple, effective, and safe treatment that reduces the risk of primary pterygium recurrence.  相似文献   
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OBJECTIVE: To determine in a placebo-controlled, double-blind trial the safety profile of daily anakinra (Kineret) use in patients with active rheumatoid arthritis (RA) and concurrent comorbid conditions. METHODS: In 169 centers in 9 countries, 1,414 patients with active RA were randomly assigned to receive either anakinra (100 mg) or placebo treatment (4:1 anakinra-to-placebo allocation ratio), with study drug administered by daily subcutaneous injection for 6 months. The current post hoc analysis assessed baseline comorbid conditions, and patients were considered at high risk for the occurrence of adverse events if they had a history of at least one of the following: cardiovascular event, pulmonary event, central nervous system-related event, infection, diabetes, malignancy, or renal impairment. Within each treatment group (anakinra or placebo), incidence rates were summarized for serious adverse events, infectious events, and serious infectious events in high-risk patients and compared with these incidence rates in patients without comorbid conditions. RESULTS: The majority of patients in the trial had one or more comorbid conditions. In these high-risk patients, there were no differences in the incidence of serious adverse events or infectious events between treatment groups. The incidence of serious infectious events with anakinra use was similar between high-risk patients (2.5%) and the entire study population (2.1%) and was not attributable to any single comorbidity. CONCLUSION: Results of the analysis of adverse events in patients with active RA and coexisting comorbidities suggest that the favorable safety profile of anakinra is maintained in a high-risk patient population.  相似文献   
996.
The increased incidence of Type I and Type II diabetes among adults and adolescents is a growing public health concern worldwide. The primary objective of diabetes mellitus management involves keeping glycemia levels within the euglycemic range to prevent a variety of serious health complications. Unfortunately, daily self-monitoring is both a requirement and a problem for many patients with diabetes, particularly children and adolescents. Studies have shown that as many as 43% of adolescents and 30% of children (<14 years old) regularly forget to use glycemic tests and are significantly poorer at recognizing and reporting symptoms and signs of hypoglycemia/hyperglycemia. For this reason, methods for noninvasive, continuous monitoring that can signal glycemic status to a parent, teacher, or other caregiver would improve the care and management of symptoms of diabetes among these individuals. The goal of this review is to describe and evaluate electronic olfaction technology ("electronic nose") for monitoring the presence and levels of volatile chemicals from human body and breath that can be used to evaluate status of diabetes. The review is organized in four sections. The first section reviews the chemistry of the volatile signals that are produced by the body that are indicative of metabolic status. The second section provides an overview of novel sensor technology, e.g., "electronic olfaction," that mimics the biological olfactory system and can be used to monitor and identify complex plumes of volatiles that are signatures of metabolic states. The third section reviews studies that have employed electronic "nose" technology for diagnosis and monitoring of diabetes via urine and breath, and the final section discusses needed future directions for the development of olfactory-based metabolic monitoring, particularly among noncompliant populations.  相似文献   
997.
This study explored the inter-relationships among state and trait anxiety, occupational stress, perfectionism, aspiration, and music performance anxiety in a group of elite operatic chorus artists employed full-time by a national opera company. The chorus artists reported higher trait anxiety, higher occupational role concerns, and higher occupational personal strain than normative samples. Higher scores on personal resources were associated with the higher scores on trait anxiety. It appears that these resources were used adaptively to manage anxiety. High trait anxiety was also associated with high personal strain in the work environment. Anxiety was not related to occupational roles or issues related to the physical environment or working conditions. These results suggest that while trait anxiety and music performance anxiety were closely associated, occupational stress makes a separate contribution to the quality of working life experienced by elite choral artists.  相似文献   
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The contributions of attention and working memory to adult age differences in concept identification were examined in two experiments using the standard version of the California Card Sorting Test plus two modified versions. Older adults demonstrated global reductions in their ability to identify concepts whether sorting stimuli, identifying concepts used by the examiner, or generating concepts from abstract cues. Although age differences in selective attention and interference control did not contribute to these deficits, reduced working memory accounted for the age-related increase in perseverative errors. Our conclusions focus on whether impairments in working memory might fully account for age differences in concept identification.  相似文献   
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