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31.
ObjectiveThe aim of study was to analyze the association between Quadriceps Angle (QA) and plantar pressure, navicular height (NH), and calcaneo-tibial angle (CTA).MethodsA total of 64 volunteers (mean age: 22.25 ± 2.54 (range:19–33)) participated in this cross sectional study. EMED-m (Novel GmbH, Germany) electronic pedobarograph was employed for dynamic plantar pressure measurement using two step protocol. The angle between the vertical axis of calcaneus and the long axis of Achilles tendon for CTA. The height of navicular tubercle from the ground was measured while the subject was standing on both feet for NH. QA was measured while the subject was standing in a relaxed posture where both feet bearing equal weight.ResultsThere were significant negative correlations between QA and maximum force (MxF) under the 4th. metatarsal head (MH4). The QA was also significantly correlated with MxF and force-time integral (FTI) under the bigtoe (BT). FTI under the 3rd. metatarsal head (MH3), MH4 and 5th. metatarsal head (MH5) were significantly negatively correlated with QA. Pressure-time integral (PTI) under the MH4 and MH5 were found to be significantly negatively correlated with QA. A significant correlation was also found between QA and NH (p < 0.0001), whilst there was no correlation between QA and CTA. Regression analysis showed that NH was appeared as the major contributor for the QA (β = −0.49, p < 0.001) in the dynamic condition, followed by BT-FTI (β = 0.37, p < 0.001) and MH5-MxF (β = −0.21, p < 0.037).ConclusionThese findings may imply that the NH which can at least be controlled by appropriate shoe inserts may affect QA. This way, loading pattern of both plantar region and whole lower extremity may be altered.Level of evidenceLevel III, Diagnostic Study.  相似文献   
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Background: Intensive blood pressure (BP) lowering may offer protective effects against major adverse cardiac event (MACE) but is also associated with a greater risk of a serious adverse event (SAE). The risk-benefit profile of intensive versus standard BP control has not been comprehensively assessed. Methods: Four studies were identified from a systematic literature search for randomized controlled trials comparing intensive versus standard BP lowering that reported both MACE and SAE endpoints. A previously described statistical approach was applied to characterize the efficacy-safety tradeoff of BP control. The bivariate outcome was computed to quantitatively assess the net clinical benefit (NCB) of intensive BP lowering as compared to standard treatment, with positive values indicating increased risks and negative values indicating decreased risks. Results: Data from the SPRINT trial demonstrated that intensive strategy was superior in MACE but inferior in SAE, thereby eroding the NCB (bivariate outcome: 0.33% [?0.50% to 1.21%]). Intensive strategy from the SPS3 trial fulfilled non-inferiority in both MACE and SAE but did not reach a favorable NCB (?1.31% [?2.25% to 0.01%]). The ACCORD trial suggested that intensive strategy was non-inferior in MACE but inferior in SAE (?0.19% [?0.79% to 1.37%]). Results from the VALISH trial were inconclusive for SAE but suggested non-inferiority in MACE (?1.19% [?3.24% to 0.68%]). Conclusions: Compared to the standard blood pressure target, pooled data from randomized controlled trials suggest that intensive strategy did not achieve a net clinical benefit when weighing the benefit of MACE reduction against the risk of SAE under the bivariate framework.Abbreviations: Blood pressure (BP), diastolic blood pressure (DBP), major adverse cardiac event (MACE), net clinical benefit (NCB), serious adverse event (SAE), systolic blood pressure (SBP).  相似文献   
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急性呼吸窘迫综合征(ARDS)是临床上常见的以顽固性低氧为表现的呼吸功能不全或衰竭的综合征,肺不均一性是其主要病理生理特点。传统观点认为,保留ARDS患者自主呼吸有助于改善全身氧合。但是近年来发现,对于重度ARDS患者,保留患者自主呼吸会加重肺损伤,过强的自主呼吸会导致重度ARDS患者跨肺压升高、肺内气体摆动、肺水肿加重以及人机不同步,引起患者肺内炎症加重,氧合功能恶化,最终影响患者预后,增加病死率。本文就自主呼吸对重度ARDS患者呼吸功能的影响机制展开综述。  相似文献   
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青光眼是致盲的主要原因之一,构成视神经的神经节细胞轴突受到多种因素的损伤,其机制尚未完全明了。青光眼最重要的危险因素是眼压升高。由于青光眼的视神经损伤尚不能直接治疗,根据目前提供的唯一已知可治疗的危险因素,可以降低升高的眼压,而眼压与房水流出通道的功能息息相关。这些方面的药物均可以影响青光眼的进展。随着医疗技术的发展以及对青光眼发病机制认识的加深,新型抗青光眼药物也应运而生,为眼科医师提供新的选择。本文将对国内外新型抗青光眼药物从机制、药理特点及临床疗效等方面进行综述。  相似文献   
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BackgroundDynamic pedobarography is used to measure the change in plantar pressure distribution during gait. Clinical methods of pedobarographic analysis lack, however, a standardized, functional segmentation or require costly motion capture technology and expertise. Furthermore, while commonly used pedobarographic measures are mostly based on peak pressures, progressive foot deformities also depend on the duration the pressure is applied, which can be quantified via impulse measures.Research QuestionOur objectives were to: (1) develop a standardized method for functionally segmenting pedobarographic data during gait without the need for motion capture; (2) compute pedobarographic measures that are based on each segment’s vertical impulse; and (3) obtain a normative set of such pedobarographic measures for non-disabled gait.MethodsPedobarographic data was collected during gait from sixty adults with normal feet. Using the maximum pressure map for each trial, an expert and novice rater independently identified the hallux, heel, medial forefoot, and lateral forefoot and computed nine normalized vertical impulse measures.ResultsFrom the computed impulse measures, the Heel-to-Forefoot Balance was 33.3 ± 5.5%, the Medial-Lateral Forefoot Balance (with hallux) 59.2 ± 8.0%, the Medial-Lateral Forefoot Balance (without hallux) 53.5 ± 7.7%, and the Hallux-to-Medial Forefoot Balance 21.0 ± 8.9% (mean ± standard deviation). The intra- and inter-rater reliability ranged between 0.93 and 1.00 and between 0.89 and 0.99, respectively (ICC(2,1)).SignificanceWe developed a simple, stand-alone method for pedobarographic segmentation that is mechanistically linked to relevant anatomical regions of the foot. The normative impulse measures exhibited excellent reliability. This normative dataset is currently used in the clinical assessment of different foot deformities and gait impairments, and in the evaluation of treatment outcomes.  相似文献   
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