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991.
992.
Mitral valve resistance determines hemodynamic consequences of severe rheumatic mitral stenosis and immediate outcomes of percutaneous valvuloplasty 下载免费PDF全文
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Glaucomatous visual field progression has both personal and societal costs and therefore has a serious impact on quality of life. At the present time, intraocular pressure (IOP) is considered to be the most important modifiable risk factor for glaucoma onset and progression. Reduction of IOP has been repeatedly demonstrated to be an effective intervention across the spectrum of glaucoma, regardless of subtype or disease stage. In the setting of approval of IOP-lowering therapies, it is expected that effects on IOP will translate into benefits in long-term patient-reported outcomes. Nonetheless, the effect of these medications on IOP and their associated risks can be consistently and objectively measured. This helps to explain why regulatory approval of new therapies in glaucoma has historically used IOP as the outcome variable. Although all approved treatments for glaucoma involve IOP reduction, patients frequently continue to progress despite treatment. It would therefore be beneficial to develop treatments that preserve visual function through mechanisms other than lowering IOP. The United States Food and Drug Administration (FDA) has stated that they will accept a clinically meaningful definition of visual field progression using Glaucoma Change Probability criteria. Nonetheless, these criteria do not take into account the time (and hence, the speed) needed to reach significant change. In this paper we provide an analysis based on the existing literature to support the hypothesis that decreasing the rate of visual field progression by 30% in a trial lasting 12–18 months is clinically meaningful. We demonstrate that a 30% decrease in rate of visual field progression can be reliably projected to have a significant effect on health-related quality of life, as defined by validated instruments designed to measure that endpoint. 相似文献
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《Journal of dentistry》2013,41(7):636-641
ObjectivesThis study examined débridement efficacy as a result of wall shear stresses created by different irrigant delivery/agitation techniques in an inaccessible recess of a curved root canal model.MethodsA reusable, curved canal cavity containing a simulated canal fin was milled into mirrored titanium blocks. Calcium hydroxide (Ca(OH)2) paste was used as debris and loaded into the canal fin. The titanium blocks were bolted together to provide a fluid-tight seal. Sodium hypochlorite was delivered at a previously-determined flow rate of 1 mL/min that produced either negligible or no irrigant extrusion pressure into the periapex for all the techniques examined. Nine irrigation delivery/agitation techniques were examined: NaviTip passive irrigation control, Max-i-Probe® side-vented needle passive irrigation, manual dynamic agitation (MDA) using non-fitting and well-fitting gutta-percha points, EndoActivator™ sonic agitation with medium and large points, VPro™ EndoSafe™ irrigation system, VPro™ StreamClean™ continuous ultrasonic irrigation and EndoVac apical negative pressure irrigation. Débridement efficacies were analysed with Kruskal–Wallis ANOVA and Dunn's multiple comparisons tests (α = 0.05).ResultsEndoVac was the only technique that removed more than 99% calcium hydroxide debris from the canal fin at the predefined flow rate. This group was significantly different (p < 0.05) from the other groups that exhibited incomplete Ca(OH)2 removal.ConclusionsThe ability of the EndoVac system to significantly clean more debris from a mechanically inaccessible recess of the model curved root canal may be caused by robust bubble formation during irrigant delivery, creating higher wall shear stresses by a two-phase air–liquid flow phenomenon that is well known in other industrial débridement systems. 相似文献
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[目的]了解老年性痴呆家庭护理者的自然、社会人口学信息及其在实施家庭护理过程中所承担的身体、精神负担。[方法]招募已被诊断为老年性痴呆病人的家庭护理者,通过电话采访录音及现场访问的方式完成统一问卷。[结果]老年性痴呆病人的家庭护理者以已婚中年妇女为主,教育程度及收入水平均较低,其中42%的受访者认为自己健康状况水平在下降,58%曾经有过负面情感的自我体验。[结论]老年性痴呆家庭护理者本身所承受的身体、精神负担应引起足够重视,可能最终影响到对病人的护理效果。 相似文献
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Ultrasound evaluation of the impact of cricoid pressure versus novel ‘paralaryngeal pressure’ on anteroposterior oesophageal diameter 下载免费PDF全文
P. Andruszkiewicz J. Wojtczak L. Wroblewski M. Kaczor D. Sobczyk I. Kowalik 《Anaesthesia》2016,71(9):1024-1029
To assess the degree to which cricoid pressure (Sellick manoeuvre) actually compresses the oesophagus, we measured the effect of cricoid pressure and paralaryngeal pressure on the outer anteroposterior diameter of the upper oesophagus with ultrasound in 39 healthy volunteers. The mean (SD) outer anteroposterior oesophageal diameter was 0.77 (0.11) cm with no pressure, 0.79 (0.13) cm with the application of cricoid pressure of 30 N and 0.68 (0.12) cm with the application of paralaryngeal pressure of 30 N (p < 0.0001). If cricoid pressure does not reduce the anteroposterior diameter of the oesophagus, it is difficult or impossible to explain the efficacy of the Sellick manoeuvre. However, paralaryngeal pressure decreases this diameter and has the potential to occlude the upper oesophagus. 相似文献
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《Sleep medicine》2017
BackgroundThere is evidence linking restless legs syndrome (RLS) with increased blood pressure (BP), but the mechanism of this relation remains unclear. Is the BP increased due to some features of RLS or to deterioration of sleep caused by RLS? This study compared values of nocturnal BP in patients with RLS and patients with insomnia. If increased BP in RLS is a consequence of disordered sleep, then it should be similar to increased BP in insomnia.MethodsPolysomnographic recordings of patients admitted to a sleep center with RLS or insomnia were analyzed. Demographic and clinical data, objective sleep parameters, and nocturnal BP were compared.ResultsRecordings of 35 patients with RLS and 33 patients with insomnia were analyzed. The groups did not significantly differ in terms of demographic traits or prevalence of other comorbidities. Patients with RLS had significantly higher systolic BP during the night (122.4 ± 13.8 vs 116.3 ± 13.4; p = 0.03) and during sleep (121.4 ± 13.3 vs 115.7 ± 13.3; p = 0.04). The only significant difference in sleep architecture was an increased number of periodic limb movements in sleep (PLMS) and PLMS with arousal in the RLS group (25.5 ± 24.6 vs 13.9 ± 22.7; p = 0.02 and 4.7 ± 5.4 vs 2.1 ± 3.4; p = 0.01).ConclusionOur results suggest that patients with RLS have higher nocturnal BP than patients with insomnia, and that increased PLMS is related to the increase in BP. 相似文献