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991.

Background  

Toll-like receptors (TLRs) are a family of pattern-recognition receptors, which plays a role in eliciting innate/adaptive immune responses and developing chronic inflammation. The polymorphisms of TLRs have been associated with the risk of various autoimmune diseases, including systemic lupus erythematosus (SLE), multiple sclerosis and rheumatorid arthritis. The aim of this study was to evaluate whether TLR genes could be used as genetic markers for the development of Graves' ophthalmopathy (GO).  相似文献   
992.

Aims  

Medical literature provides only scarce data about the degree of pain experienced by patients undergoing a bone marrow aspiration and biopsy (BMAB), and little is known about the factors that can modify the perception of pain. In this study, we evaluated the effectiveness of a combination of analgesia and anxiolysis in reducing the pain score of patients undergoing BMAB.  相似文献   
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Tracheal cartilage has been widely regarded as a linear elastic material either in experimental studies or in analytic and numerical models. However, it has been recently demonstrated that, like other fiber-oriented biological tissues, tracheal cartilage is a nonlinear material, which displays higher strength in compression than in extension. Considering the nonlinearity requires a more complex theoretical frame work and costs more to simulate. This study aims to quantify the deviation due to the simplified treatment of the tracheal cartilage as a linear material. It also evaluates the improved accuracy gained by considering the nonlinearity. Pig tracheal rings were used to exam the mechanical properties of cartilage and muscular membrane. By taking into account the asymmetric shape of tracheal cartilage, the collapse behavior of complete rings was simulated, and the compliance of airway and stress in the muscular membrane were discussed. The results obtained were compared with those assuming linear mechanical properties. The following results were found: (1) Models based on both types of material properties give a small difference in representing collapse behavior; (2) regarding compliance, the relative difference is big, ranging from 10 to 40% under negative pressure conditions; and (3) the difference in determining stress in the muscular membrane is small too: <5%. In conclusion, treating tracheal cartilage as a linear material will not cause big deviations in representing the collapse behavior, and mechanical stress in the muscular part, but it will induce a big deviation in predicting the compliance, particularly when the transmural pressure is lower than −0.5 kPa. The results obtained in this study may be useful in both understanding the collapse behavior of trachea and in evaluating the error induced by the simplification of treating the tracheal cartilage as a linear elastic material.  相似文献   
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The purpose of this study was to determine the rates and causes of revisits to the emergency department (ED) of a 3,500-bed referral hospital, to identify areas for improvement, and to generate baseline data for the development of a computerized, automatic monthly audit system. We identified all patients returning within 72 hours of their initial ED visits, from 1 July 1995 to 30 June 1997, and monthly revisit rates were calculated. To determine the reasons for revisits, two independent reviewers examined the charts of revisit cases from 1 July 1996 to 30 June 1997. A one-in-three sampling method was used to select charts. A total of 485 revisit charts were reviewed. The monthly revisit rates ranged from 1.32% to 2.38%, with no particular seasonal or event-specific pattern. Most revisits were attributed to disease factors (79.0%). Those felt to be medical errors only accounted for 7.8% of the revisits but led to a higher hospital admission rate (73.7%) subsequently. By contrast, the overall hospital admission rates for revisit patients (36.5%) and all ED patients (36.2%) were similar. We suggest setting baseline monthly ED revisit rates at 2% for future computer-programmed audit filters. While this study indicates that most revisits are disease-related, further prospective studies are needed to evaluate the most common and serious causes of revisits to see if improvements can be made.  相似文献   
1000.
近视眼黄斑区视网膜厚度的研究   总被引:2,自引:0,他引:2  
李娜  廖华萍  俞方知  王玲 《眼科研究》2008,26(6):436-438
目的 探讨近视眼黄斑区视网膜厚度的特点.方法 122例除视盘旁近视弧外无其他眼部异常的近视患者,等效球镜度数-1.50~-15.25 D(-6.18±2.61)D,每例随机选取1眼受检.所有受检眼行屈光检查和眼轴长度测定.将黄斑区分为9个区域,测定各区域视网膜厚度后,进行相关因素分析.结果 受检者黄斑中心凹视网膜厚度与年龄及眼轴长度均不相关.旁中心各区域视网膜厚度与年龄不相关,与眼轴长度呈负相关,鼻侧内圈除外;随眼轴增长,外圈视网膜厚度较内圈变薄明显.结论 随着近视眼眼轴长度增加,除黄斑中心凹视网膜厚度无变化外,旁中心视网膜厚度呈变薄趋势,且外圈变薄较内圈明显.  相似文献   
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