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排序方式: 共有4100条查询结果,搜索用时 15 毫秒
1.
目的:应用99mTc-DTPA肾动脉显像评价Stanford不同分型主动脉夹层患者术后左、右侧肾功能及总体肾功能受损程度,帮助临床制定进一步的治疗方案,改善患者预后。方法:回顾性分析2018年3月8日至2019年7月19日,在本院核医学科行99mTc-DTPA肾动态显像的主动脉夹层术后患者48例,评价患者双肾血流灌注、总肾小球滤过率(GFR)和分肾的GFR,比较Stanford主动脉夹层A型(简称A型)患者和主动脉夹层B型(简称B型)患者之间总肾功能及分肾功能,血肌酐、血尿素氮及血尿酸水平的差异。结果:B型患者术后总GFR低于A型患者(67.5 vs.80.6 m L/min,P<0.05),其中以左肾功能受损为著(30.9 vs.40.3 m L/min,P<0.05),差异有统计学意义。结论:肾动态显像对主动脉夹层术后患者早期评价肾功能有重要价值。主动脉夹层B型患者GFR较A型减低,且左侧肾GFR减低更明显,临床可以早期采取干预措施,改善主动脉夹层患者预后。  相似文献   
2.
目的:评定LC-MS/MS法测定人血浆中布康唑浓度的不确定度。方法:分析测定过程中不确定度的来源,包括对照品的称量、仪器误差、标准溶液的配制、含药血浆样品的配制、血浆样品的处理、标准曲线的拟合、基质效应、重复性等,评定各来源分量的不确定度,计算合成不确定度和扩展不确定度。结果:人血浆中低(60.0 pg·mL-1)、中(600.0 pg·mL-1)、高(6 400.0 pg·mL-1)浓度布康唑的扩展不确定度分别为5.62,63.90,626.26 pg·mL-1k=2,P=95%)。结论:LC-MS/MS法测定人血浆中布康唑浓度的不确定度主要由基质效应、血浆样品的处理(提取回收率),仪器误差、重复性(精密度)引入。  相似文献   
3.
Background and aimPatient decision aids for oncological treatment options, provide information on the effect on recurrence rates and/or survival benefit, and on side-effects and/or burden of different treatment options. However, often uncertainty exists around the probability estimates for recurrence/survival and side-effects which is too relevant to be ignored. Evidence is lacking on the best way to communicate these uncertainties. The aim of this study is to develop a method to incorporate uncertainties in a patient decision aid for breast cancer patients to support their decision on radiotherapy.MethodsFirstly, qualitative interviews were held with patients and health care professionals. Secondly, in the development phase, thinking aloud sessions were organized with four patients and 12 health care professionals, individual and group-wise.ResultsConsensus was reached on a pictograph illustrating the whole range of uncertainty for local recurrence risks, in combination with textual explanation that a more exact personalized risk would be given by their own physician. The pictograph consisted of 100 female icons in a 10 x 10 array. Icons with a stepwise gradient color indicated the uncertainty margin. The prevalence and severity of possible side-effects were explained using verbal labels.ConclusionsWe developed a novel way of visualizing uncertainties in recurrence rates in a patient decision aid. The effect of this way of communicating risk uncertainty is currently being tested in the BRASA study (NCT03375801).  相似文献   
4.
Standard cost-effectiveness models compare incremental cost increases to incremental average gains in health, commonly expressed in Quality-Adjusted Life Years (QALYs). Our research generalizes earlier models in several ways. We introduce risk aversion in Quality of Life (QoL), which leads to “willingness-to-pay” thresholds that rise with illness severity, potentially by an order of magnitude. Unlike traditional CEA analyses, which discriminate against persons with disabilities, our analysis implies that the marginal value of improving QoL rises for disabled individuals. Our model can also value the uncertain benefits of medical interventions by employing well-established analytic methods from finance. Finally, we show that traditional QALYs no longer serve as a single index of health, when consumers are risk-averse. To address this problem, we derive a generalized single-index of health outcomes—the Generalized Risk-Adjusted QALY (GRA-QALY). Earlier models of CEA that abstract from risk-aversion nest as special cases of our more general model.  相似文献   
5.
Animal behaviour can be viewed as a stream of elements, which, once accurately described, can be counted and timed. Data acquisition techniques and tools are reviewed, and some strategies for collection and analysis of data using PC computers are suggested. Automated instruments are not satisfactory for the study of complex behaviour and as such systemic observation remains irreplaceable. IBM PC-type computers, with a wide range of analytical software (e.g., spreadsheets, statistical packages, technical graphics), are practical for data acquisition. Several systems which can satisfy different applications are reviewed. Some systems can communicate with a videorecorder, a facility which remarkably increases the accuracy of measurement; this is essential for meaningful analyses of the internal structure of behavioural streams (sequences, time patterns) or communication processes. The power of new tools enables behavioural measurement with the necessary complexity to allow a whole new set of questions to be addressed. However, it also increases demands for meaningful content and analysis of data.  相似文献   
6.
We provide further evidence for the two-factor structure of the 9-item Academic Expectations Stress Inventory (AESI) using confirmatory factor analysis on a sample of 289 Canadian adolescents and 310 Singaporean adolescents. Examination of measurement invariance tests the assumption that the model underlying a set of scores is directly comparable across groups. This study also examined the cross-cultural validity of the AESI using multigroup confirmatory factor analysis across both the Canadian and Singaporean adolescent samples. The results suggested cross-cultural invariance of form, factor loadings, and factor variances and covariances of the AESI across both samples. Evidence of AESI's convergent and discriminant validity was also reported. Findings from t-tests revealed that Singaporean adolescents reported a significantly higher level of academic stress arising from self expectations, other expectations, and overall academic stress, compared to Canadian adolescents. Also, a larger cross-cultural effect was associated with academic stress arising from other expectations compared with academic stress arising from self expectations.  相似文献   
7.
3种氟喹诺酮类药物抗生素后效应的研究   总被引:40,自引:2,他引:38  
应用AVANTAGF分析仪的光密度法测定了环丙沙星(CPLX)、氧氟沙星(OFLX)和氟罗沙星(FLRX)的抗生素后效应(PAE).结果表明氟喹诺酮类抗菌药物对革兰氏阳性球菌和革兰氏阴性杆菌均产生明显的PAE.并随抗菌药物浓度的增大、对受试菌的PAE逐渐延长.呈现了明显的浓度依赖性;3种抗菌药物对铜绿假单胞菌的PAE都较长.MIC均较小.显示了良好的杀菌效果:氯罗沙星对除金葡球菌之外的受试菌的PAE均比其它2药较长.PAE的存在提示在临床设计给药方案时.可适当延长给药间期.减少给药次数与剂量.仍能维持抗菌效果。  相似文献   
8.
This paper introduces a design methodology for a dynamic compensator that simultaneously minimizes the upper bound of a quadratic performance index and the H-norm of a disturbance transfer function matrix of a multiple-input/multiple-output system whose model contains parameter uncertainty in the state and input matrices. The real parameter uncertainty is modelled as additional measurement outputs and as additional weights on the existing noise inputs and measurement outputs of the system. The compensator equations are derived by taking the dual of a system with parameter variation in the state and output matrices, for which the compensator equations have previously been derived, and then taking the dual of the compensator equations. An algorithm for applying this theory is given and an example is shown.  相似文献   
9.
目的通过应用痛觉测试笔测试痛觉平面,探讨其临床应用的实用性。方法选择100名志愿者观察痛觉测试笔产生刺痛感的定性描述,另500例行硬膜外阻滞的患者用针刺法和测试笔同时间同检查部位测试。结果100名志愿者认为痛觉测试笔对皮肤只引起如针刺样疼痛,每次测试产生刺痛程度一致,不产生肌肉抽搐、不放散。500例行硬膜外阻滞患者针刺法和测试笔测得的麻醉平面一致,测试笔无划痕反应。结论测试笔可替代锐器针刺法检测麻醉平面,可减少针刺法引起的皮肤损伤。  相似文献   
10.
目的介绍一种简单实用而较精确的测量狭窄气管截面积的方法.方法利用纤维支气管镜、测长器、模拟气管等制作并校正测量标尺,并利用该标尺测量了3例气管状况异常患者的气管某一截面面积.结果用校正过的4种测量标尺测量了10个模拟气管的直径,和实测真值比较经t检验分析无显著性差异,利用上述标尺测量的3个患者的目的截面面积分别为约96 mm2、 105 mm2和192 mm2.结论本方法提供了一种简单、快速而又较精确的测量大气道某一截面面积的方法,为定量评价患者的通气功能、选择气管支架或采用其他干预手段处理气管病变提供了数据参考.  相似文献   
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