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61.
Christina Djokoto George Tomlinson Stephen Waldman Marc Grynpas Angela M. Cheung 《Journal of clinical densitometry》2004,7(4):448-456
Dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) are the accepted modalities for the evaluation of fracture risk in the clinical setting. However, neither method provides a direct measurement of bone mechanics. In this study, we investigated a prototype device, known as a mechanical response tissue analyzer (MRTA), which provides direct mechanical measurements of mechanical properties of bone. A total of 56 healthy volunteers (20 men and 36 women) between the ages of 18 and 83 were recruited. The MRTA was used to measure the cross-sectional bending stiffness (EI) of the ulna bone. Axial speed of sound (SOS) at the ulna bone was determined by QUS; bone mineral content (BMC) and bone mineral density (BMD) were determined by DXA. Correlations, regression analysis, and analyses of variance (ANOVAs) were used to compare the three modalities. These analyses revealed that although there are strong linear relationships among the data collected by the various technologies, the bone properties reflected by MRTA are not fully explained by DXA and QUS. We conclude that the total information conveyed by MRTA measurements is unique. Further research is needed to delineate the different qualities of bone strength that are captured by MRTA, but not by DXA or QUS. 相似文献
62.
一次和多次住院精神分裂症患者再住院分析 总被引:9,自引:0,他引:9
目的 :比较 1次和≥ 2次住院精神分裂症患者出院后的再住院率 ,初步探讨影响再住院的相关因素。 方法 :1999年度出院的 833例住院精神分裂症患者纳入调查 ,使用自制的再住院及其相关因素调查表 ,于 2 0 0 3年 12月底前电话或入户调查出院后至少 4 8个月的情况。 结果 :6 6 4例完成调查 ,分为 1次住院组 (333例 )和多次住院组 (331例 )。用生存分析 (Kaplan Meier公式 )比较两组未再住院率 ,12个月末 (分别为 6 7 0 %和 6 1 6 % )、2 4个月末 (5 6 2 %和 4 8 9% )、36个月末 (4 6 0和 35 1% )和 4 8个月末 (4 1 1%和 2 8 7% )。Cox回归风险比例模型分析影响再住院的相关因素显示 ,与药物依从性、生活事件、自知力和家庭照顾相关 (P <0 0 5 ) ,药物依从性对再住院的贡献值 (1 719)最大。 结论 :1次住院精神分裂症患者出院后的再住院率较多次住院者低。药物依从性是影响再住院的主要因素 相似文献
63.
Differential Stripping: Determination of the Amount of Topically Applied Substances Penetrated into the Hair Follicles 下载免费PDF全文
Alexa Teichmann Ute Jacobi Michael Ossadnik† Heike Richter Stefan Koch† Wolfram Sterry Jürgen Lademann 《Journal of general internal medicine》2005,20(5):264-269
The determination of penetration pathways of topically applied substances into the skin is the subject of several investigations. Recently, follicular penetration has become a major focus of interest. To date, a direct, non-invasive quantification of the amount of topically applied substance penetrated into the follicles had not been possible. The development of such a method was the aim of this study. Therefore, the advantages of both stripping techniques, tape stripping and cyanoacrylate skin surface biopsy, were combined and evaluated. Tape stripping was used to remove the part of the stratum corneum that contained the topically applied dye. Subsequently, the follicular contents were ripped off by cyanoacrylate skin surface biopsy. The combined method termed "differential stripping" was evaluated in vitro and in vivo , and the amount of topically applied fluorescent dye penetrated into the hair follicles was quantified after different penetration times. After 30 min, 5% of the recovered concentration of sodium fluorescein was found in the follicular infundibula, where it was still detectable after 48 h. Altogether, the results of this investigation revealed that differential stripping is a new method that can be used to study the penetration of topically applied substances into the follicular infundibula non-invasively and selectively. 相似文献
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目的探讨心力衰竭并发心律失常的发病规律及治疗方法。方法回顾性分析了93例慢性心力衰竭病人的临床资料,包括临床特点、诊断治疗方法以及预后。结果心律失常发生率为60.2%,以室性早搏发生率最高32.1%,其次是房性早搏26.8%,心房纤颤21.4%,其他19.7%,经治疗有效71例,总有效率76.3%。结论纠正心功能不全是治疗的关键,应根据具体情况选择性地应用抗心律失常药。 相似文献
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Decisions about which health-care interventions represent adequate value to collectively funded health-care systems are as widespread as they are unavoidable. In the case of new pharmaceuticals, many countries now require formal cost-effectiveness analysis to inform this decision-making process. This requires evidence on parameters associated with health-related utilities, treatment effects, resource use, and costs, for which data from available regulatory trials are invariably absent or highly uncertain. This uncertainty results from a number of factors including the predominance of intermediate end points in the clinical evidence-base and the limited period of follow-up of patients in clinical studies. Despite these imperfections in the evidence base, decisions about whether new pharmaceuticals are sufficiently cost-effective for reimbursement cannot be side-stepped. Data limitations do, however, require the use of rigorous analytical methods to support decision making. Probabilistic decision models and value of information analysis offer a means of structuring decision problems, synthesizing all available data, characterizing the uncertainty in the decision, quantifying the cost of uncertainty, and establishing the expected value of perfect information. This analytical framework is important because it addresses two fundamental questions about new pharmaceuticals. First, is the product expected to be cost-effective on the basis of existing evidence? Second, is additional research concerning the product itself cost-effective? In addressing these questions, the analytical framework can establish when sufficient evidence exists to sustain a claim for a new pharmaceutical to be cost-effective. 相似文献
70.
本实验研究了兔视网膜中的方向选择性神经节细胞 (direction selective retinal ganglion cells,DS cells)树突野的分枝模式。测量了视网膜中方向选择性神经节细胞和作为经典分枝模式神经元代表的α神经节细胞的树突直径。发现 ,方向选择性神经节细胞的树突在分枝后直径达到 0 .5 μm,进一步分枝树突直径仍保持在 0 .5 μm左右 ,这样 ,在方向选择性神经节细胞树突野中大多数树突直径在 0 .5μm左右。而作为经典分枝模式神经元代表的α神经元的树突每次分枝后都逐级变细 ,最终直径达到 0 .5μm左右 ,这样 ,α神经节细胞的树突直径大部分都大于 0 .5μm。我们应用程序“NEU RON”对在两种神经元模型中 ,抑制点落于兴奋点与胞体之间 (proximal)和抑制点不落于兴奋点与胞体之间 (distal)这两种情况进行模拟。我们发现 ,当抑制点不落于兴奋点与胞体之间时 ,在方向选择性神经节细胞的树突分枝模型中 ,抑制效果更强。那么 ,将使得方向选择性神经节细胞对抑制点落于兴奋点和胞体之间的要求变得不是那么迫切。所以 ,方向选择性神经节细胞的这种独特分枝模式 ,也许可以避免或至少减轻其在发育中可能会产生的连线的复杂性。并且 ,我们对得出的结论进行了电路分析 ,对方向选择性神经节细胞这种独特的分枝模式具有的? 相似文献