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121.
Clinicians and public health experts make evidence-based decisions for individual patients, patient groups and even whole populations. In addition to the principles of internal and external validity (evidence), patient preferences must also influence decision making. Great Britain, Australia and Germany are currently discussing methods and procedures for valuing patient preferences in regulatory (authorization and pricing) and in health policy decision making. However, many questions remain on how to best balance patient and public preferences with physicians’ judgement in healthcare and health policy decision making. For example, how to define evaluation criteria regarding the perceived value from a patient’s perspective? How do physicians’ fact-based opinions also reflect patients’ preferences based on personal values? Can empirically grounded theories explain differences between patients and experts—and, if so, how? This article aims to identify and compare studies that used different preference elicitation methods and to highlight differences between patient and physician preferences. Therefore, studies comparing patient preferences and physician judgements were analysed in a review. This review shows a limited amount of literature analysing and comparing patient and physician preferences for healthcare interventions and outcomes. Moreover, it shows that methodology used to compare preferences is diverse. A total of 46 studies used the following methods—discrete-choice experiments, conjoint analyses, standard gamble, time trade-offs and paired comparisons—to compare patient preferences with doctor judgements. All studies were published between 1985 and 2011. Most studies reveal a disparity between the preferences of actual patients and those of physicians. For most conditions, physicians underestimated the impact of intervention characteristics on patients’ decision making. Differentiated perceptions may reflect ineffective communication between the provider and the patient. This in turn may keep physicians from fully appreciating the impact of certain medical conditions on patient preferences. Because differences exist between physicians’ judgement and patient preferences, it is important to incorporate the needs and wants of the patient into treatment decisions.  相似文献   
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The purpose of this work was to investigate the performance of the modified BIR‐4 T2 preparation for T2 mapping and propose a method to remove T2 quantification errors in the presence of large B1 and B0 offsets. The theoretical investigation of the magnetization evolution during the T2 preparation in the presence of B1 and B0 offsets showed deviations from a mono‐exponential T2 decay (two parameter fit). A three parameter fit was used to improve T2 accuracy. Furthermore, a two parameter fit with an additional saturation preparation scan was proposed to improve T2 accuracy and precision. These three fitting methods were compared based on simulations, phantom measurements and an in vivo healthy volunteer study of the neck musculature using a 3D TSE readout. The results based upon the pure two parameter fit overestimated T2 in regions with high B0 offsets (up to 40% in phantoms). The three parameter fit T2 values were robust to B0 offsets but with higher standard deviation (up to 40% in simulations). The two parameter fit with the saturation preparation yielded high robustness towards B0 offsets with a noise performance comparable to that of the two parameter fit. In the volunteer study the T2 values obtained by the pure two parameter fit showed a dependence on the field inhomogeneities, whereas the T2 values from the proposed fitting approach were shown to be insensitive to B0 offsets. The proposed method enabled accurate and precise T2 mapping in the presence of large B1 and B0 offsets.  相似文献   
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Background  

In addition to the activation of hepatic stellate cells TGF-β govern apoptosis and growth control of hepatocytes in liver injury. In non-parenchymal cells, TGF-β induces plasminogen activator inhibitor 1 (PAI-1) and connective tissue growth factor (CTGF) expression, which are involved in extra cellular matrix formation. Both genes were also regulated by glucocorticoids, which in certain cases showed antagonistic effects to the TGF-β-Smad 3 pathway. The purpose of our work was to investigate the influence of TGF-β and dexamethasone on PAI-1 and CTGF expression and secretion in primary hepatocytes.  相似文献   
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OBJECTIVE: To investigate the haemodynamic effects of levosimendan in patients with cardiogenic shock (CS) complicating acute myocardial infarction in comparison to the effects of intra-aortic balloon counterpulsation (IABP). METHODS: 10 patients with intractable CS under standard therapy (including the use of PCI, inotropes, and vasopressors) received i.v. infusion of levosimendan (bolus 12 microg/kg i.v., followed by continuous infusion 0.1 microg/kg/min for 24 h). Haemodynamic effects were compared to the effects of IABP-placement added to standard care in 12 patients with CS. RESULTS: Within 24 h, both levosimendan and IABP produced a significant increase in cardiac index (CI) and cardiac power index and a decrease in systemic vascular resistance (SVR) (CI [l/min/m2] baseline 1.97+/-0.15, at 24 h 2.82+/-0.22 for levosimendan; baseline 1.98+/-0.17, at 24 h 2.66+/-0.08 for IABP; SVR [dyn*s*cm-5] baseline 1353+/-106, at 24 h 846+/-69 for levosimendan; baseline 1311+/-214, at 24 h 853+/-63 for IABP, respectively). After 3 h of treatment, CI and SVR had significantly improved in patients treated with levosimendan but not in the IABP-group (CI [l/min/m2] at 3 h 2.72+/-0.28 (+38%) for levosimendan versus 2.18+/-0.15 (+10%) for IABP). CONCLUSION: Infusion of levosimendan in acute CS results in early and sustained haemodynamic improvement. Short-term haemodynamic effects compare favourably with those seen after invasive IABP placement.  相似文献   
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Multiple studies comparing sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES) in patients with coronary artery disease have been performed. Despite these comparisons, it remains uncertain whether a differential in long-term efficacy and safety exists. Unselected patients treated exclusively with 1 drug-eluting stent type were enrolled in the Registry Experience at the Washington Hospital Center with Drug-Eluting Stents. There were 2,099 patients (3,766 lesions) treated with SES and 1,079 patients (1,850 lesions) treated with PES. Patients were followed at 30 days, 1 year, and 2 years for the clinical endpoints of death, myocardial infarction, target vessel revascularization, and definite and definite/probable stent thrombosis. Patients in the SES group had more dyslipidemia, history of congestive heart failure, and ostial lesions; patients treated with PES had more previous coronary artery bypass surgery, unstable angina, and type C lesions. At 2 years, unadjusted major adverse cardiac events (MACE) (22.6% vs 21.1%, p = 0.3) and target vessel revascularization (13.3% vs 11.2%, p = 0.1) were comparable. The incidence of definite stent thrombosis was higher in the SES group (1.8% vs 0.9%, p = 0.05) driven by early events. Similar results were seen after adjustment for baseline differences: MACE (hazard ratio 1.1, 95% confidence interval [CI] 0.9 to 1.3, p = 0.5), definite stent thrombosis (hazard ratio 2.3, 95% CI 1.0 to 5.2, p = 0.05), and target vessel revascularization (hazard ratio 1.1, 95% CI 0.9 to 1.4, p = 0.4). The incidence and rate of late stent thrombosis (>30 days) were similar (0.7% vs 0.5%, p = 0.4 and 0.24%/year, both groups, respectively). In conclusion, no major differential in long-term safety or efficacy was detected between SES and PES; both stent types were efficacious in reducing revascularization but were limited by a small continual increase in late stent thrombosis.  相似文献   
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For patients undergoing elective percutaneous coronary intervention (PCI), procedural anticoagulation with bivalirudin was previously shown to significantly reduce bleeding complications at the cost of a modest increase in ischemic events compared with unfractionated heparin (UFH) and glycoprotein IIb/IIIa inhibitors (GPIs). However, the excess bleeding in patients treated with UFH and GPIs may have been caused by excessively high UFH doses and increased activated clotting times. This study sought to determine the bleeding risk of targeted low-dose UFH with GPIs compared with bivalirudin in patients undergoing elective PCI. Of 1,205 patients undergoing elective PCI, 602 underwent PCI with adjunctive UFH and GPIs with the UFH dose targeted to an activated clotting time of approximately 250 seconds, and 603 patients matched for baseline characteristics underwent PCI with bivalirudin. Outcomes were analyzed for major bleeding (hematocrit decrease >15%, gastrointestinal bleed, or major hematoma) and 6-month major adverse cardiac events (death, myocardial infarction, and target-lesion revascularization). The maximum activated clotting time achieved was 261.7 +/- 61.6 seconds in the UFH/GPI group and 355.4 +/- 66.6 in the bivalirudin group (p <0.001). In-hospital major bleeding rates were similar between groups (1.8% UFH/GPI vs 1.7% bivalirudin; p = 0.83), as were transfusion requirements (1.2% UFH/GPI vs 0.5% bivalirudin; p = 0.61). The 6-month major adverse cardiac event rate was also similar between groups (9.5% UFH/GPI vs 9.0% bivalirudin; p = 0.81). In conclusion, there were no significant differences in major bleeding and 6-month major adverse cardiac events for patients undergoing elective PCI treated with targeted low-dose UFH and GPIs compared with those treated with bivalirudin.  相似文献   
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