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Timely diagnosis of osseous tumors is essential in providing proper management. Appropriate imaging studies are essential to this process, however, if inconclusive, they can be superceded by information obtained through the patient history and physical examination. Disclaimer: Dr. Bhandari's salary was provided, in part, by a scholarship from the R.K Frasier Research Foundation  相似文献   
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In the past 3 years there have been five further cases, in additionto one case reported in 1985, of Creutzfeldt-Jakob disease inrecipients of human growth hormone in the United Kingdom. Theclinical findings of two of these cases are described, demonstratinga typical presentation with a predominantly cerebellar syndromeat onset which is not commonly a presenting feature of sporadicCreutzfeldt-Jakob disease. In one case a 99mTc hexamethylpropylenaminesingle photon emission tomographic scan showed marked impairmentof tracer uptake in the basal ganglia and cerebral cortex ata time when the clinical picture was predominantly cerebellar.This technique may be useful in early diagnosis. In the othercase post mortem examination of the brain showed prominent amyloiddeposition in the cerebellum, which has not been described previouslyin pituitary-hormone related Creutzfeldt-Jakob disease. Thepreviously published cases of growth hormone-related Creutzfeldt-Jakobdisease are reviewed and reasons for the particular clinicalpattern seen are discussed.  相似文献   
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番茄红素与成骨细胞、破骨细胞及骨质疏松症   总被引:1,自引:0,他引:1  
学术背景:骨质疏松症是较易发生的疾病,研究骨质疏松的发病机制寻找治疗骨质疏松的药物是预防老年性骨质疏松症的理想选择。目的:综述近几年来国内外关于氧化应激及番茄红素在骨质疏松发病中的作用的相关研究,为开发预防和治疗骨质骨质疏松的药物提供理论依据。检索策略:应用计算机检索Medline和Science Direct Online数据库1989-01/2007-04期间的相关文章,检索词为"oxidative stress,osteoclast,osteoblast,lycopene,osteoporosis",限定文章语言种类为English。同时计算机检索中国期刊全文数据库2000-01/2007-04期间的相关文章,检索词为"氧化应激,骨质疏松,成骨细胞,破骨细胞,番茄红素",限定文章语言种类为中文。对资料进行初审,选择有关人体内氧化应激形成机制、氧化应激与成骨细胞、氧化应激与破骨细胞、氧化应激与抗氧化剂、番茄红素与成骨细胞及破骨细胞和番茄红素与骨质疏松症关系的最新进展文献,共收集到121篇,排除综述类及重复研究。文献评价:符合纳入标准的31篇文献中,5篇涉及骨质疏松症的概述,20篇涉及氧化应激和抗氧化剂在骨质疏松症发病中作用的相关研究,6篇涉及番茄红素与氧化应激、成骨细胞、破骨细胞及绝经后骨质疏松关系的相关研究。资料综合:氧化应激是骨质疏松发病的一个危险因素。氧化应激不但作用于成骨细胞还作用于破骨细胞。国内外学者对于番茄红素的抗氧化性能研究取得了很大进展,已通过细胞培养观察到其对成骨细胞和破骨细胞均有作用,通过临床研究发现,番茄红素通过其抗氧化功能而影响成骨细胞和破骨细胞的功能,从而能够对骨质疏松症发生发展的病理过程进行有效干预,最终阻止和减缓骨质疏松症的发生。结论:番茄红素具有的抗氧化功能使其在骨质疏松的预防及治疗方面起着重要的作用。  相似文献   
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Background contextLow back pain (LBP) is associated with high health-care utilization and lost productivity. Numerous interventions are routinely used, although few are supported by strong evidence. Cost utility analyses (CUAs) may be helpful to inform decision makers.PurposeTo conduct a systematic review of CUAs of interventions for LBP.Study designSystematic review.MethodsA search strategy combining medical subject headings and free text related to LBP and health economic evaluations was executed in MEDLINE. Cost utility analyses combined with randomized controlled trials for LBP were included. Studies that were published before 1998, non-English, decision analyses, and duplicate reports were excluded. Search results were evaluated by two reviewers, who extracted data independently related to clinical study design, economic study design, direct cost components, utility results, cost results, and CUA results.ResultsThe search produced 319 citations, and of these 15 met eligibility criteria. Most were from the United Kingdom (n=8), published in the past 3 years (n=12), studied chronic LBP or radiculopathy (n=13), and had a follow-up >12 months (n=13). Combined, there were 33 study groups who received a mean 2.1 interventions, most commonly education (n=17), exercise therapy (n=13), spinal manipulation therapy (n=7), surgery (n=7), and usual care from a general practitioner (n=7). Mean baseline utility was 0.57, improving to 0.67 at follow-up; the mean difference in utility improvement between study groups was 0.04. Based on available data and converted to US dollars, the cost per quality-adjusted life year ranged from $304 to $579,527, with a median of $13,015.ConclusionsFew CUAs were identified for LBP, and there was heterogeneity in the interventions compared, direct cost components measured, indirect costs, other methods, and results. Reporting quality was mixed. Currently published CUAs do not provide sufficient information to assist decision makers. Future CUAs should attempt to measure all known direct cost components relevant to LBP, estimate indirect costs such as lost productivity, have a follow-up period sufficient to capture meaningful changes, and clearly report methods and results to facilitate interpretation and comparison.  相似文献   
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