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Background: While over half of stroke survivors recover the ability to walk without assistance, deficits persist in the performance of walking adaptations necessary for safe home and community mobility. One such adaptation is the ability to walk or step backward. Post-stroke rehabilitation rarely includes backward walking (BW) assessment and BW deficits have not been quantified in post-stroke community ambulators.

Objective: To quantify spatiotemporal and kinematic BW characteristics in post-stroke community ambulators and compare their performance to controls.

Methods: Individuals post-stroke (n = 15, 60.1 ± 12.9 years, forward speed: 1.13 ± 0.23 m/s) and healthy adults (n = 12, 61.2 ± 16.2 years, forward speed: 1.40 ± 0.13 m/s) performed forward walking (FW) and BW during a single session. Step characteristics and peak lower extremity joint angles were extracted using 3D motion analysis and analyzed with mixed-method ANOVAs (group, walking condition).

Results: The stroke group demonstrated greater reductions in speed, step length and cadence and a greater increase in double-support time during BW compared to FW (p < .01). Compared to FW, the post-stroke group demonstrated greater reductions in hip extension and knee flexion during BW (p < .05). The control group demonstrated decreased plantarflexion and increased dorsiflexion during BW, but these increases were attenuated in the post-stroke group (p < .05).

Conclusions: Assessment of BW can unmask post-stroke walking impairments not detected during typical FW. BW impairments may contribute to the mobility difficulties reported by adults post-stroke. Therefore, BW should be assessed when determining readiness for home and community ambulation.  相似文献   

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The Mouse Genome Analysis Consortium aligned the human and mouse genome sequences for a variety of purposes, using alignment programs that suited the various needs. For investigating issues regarding genome evolution, a particularly sensitive method was needed to permit alignment of a large proportion of the neutrally evolving regions. We selected a program called BLASTZ, an independent implementation of the Gapped BLAST algorithm specifically designed for aligning two long genomic sequences. BLASTZ was subsequently modified, both to attain efficiency adequate for aligning entire mammalian genomes and to increase its sensitivity. This work describes BLASTZ, its modifications, the hardware environment on which we run it, and several empirical studies to validate its results.  相似文献   
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The case of a woman presenting with a ureterocutaneous fistula 40 years after nephrectomy is described. Because of advanced respiratory disease and absence of infective activity, a conservative line of treatment with saline rinse was given. At 3 months follow-up the fistula had become chronic, with a small opening without signs of infection and ultrasound revealed no abscess.  相似文献   
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In the present work, we provide a comprehensive numerical investigation of the magnetic properties and phase spectra of three types of spin-1/2 branched chains consisting of one, two and three side spins per unit block with intra-chain interaction and a uniform inter-chain interaction in the presence of an external magnetic field. In a specific magnetic field interval, the low-temperature magnetization of these chains shows a step-like behavior with a pronounced plateau depending on the strength and the type of intra-chain interaction being ferromagnetic or antiferromagnetic. We demonstrate that when inter-chain interaction J1 is antiferromagnetic and intra-chain interaction J2 is ferromagnetic, the magnetization of the models manifests a smooth increase without a plateau, which is evidence of the existence of a Luttinger-like spin liquid phase before reaching its saturation value. On the other hand, when J1 is ferromagnetic and J2 is antiferromagnetic, the low-temperature magnetization of the chain with two branches shows an intermediate plateau at one-half of the saturation magnetization that breaks a quantum spin liquid phase into two regions. The magnetization of the chain with three branches exhibits two intermediate plateaus and two regions of a quantum spin liquid. We demonstrate that the chains with more than one side spin illustrate in their ground-state phase diagram a Kosterlitz–Thouless transition from a gapful phase to a gapless spin liquid phase.  相似文献   
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BackgroundPregnancy is a major concern among women with the sickle cell disease (SCD), and it is associated with increased adverse outcomes. The aim of the present meta-analysis is to report the fetomaternal outcomes in different sickle cell genotypes.MethodsIn this systematic review and meta-analysis, a comprehensive search of databases and search engines such as PubMed, Scopus, Web of Science, ProQuest, Cochrane Library, Science Direct and Google Scholar were performed. Any observational studies that had compared at least one outcome such as maternal outcomes, fetal outcomes, and morbidity between two groups of pregnant women with different types of sickle cell genotypes and pregnant women without SCD were evaluated.ResultsA total number of 9,827 pregnant women with SCD were examined. The results showed that pregnancy in SCD increased the risk of adverse outcomes for the mothers (including postpartum hemorrhage, prematurity, pregnancy-induced hypertension, pre-eclampsia, eclampsia, cesarean section, lower segment cesareansection, maternal death), fetus (including live births, low birth weight, intrauterine growth restriction, APGAR score at 5 min <7, stillbirth, neonatal death, perinatal mortality, acute fetal distress, intrauterine fetal death) and morbidity among the SCD(severe anemia, urinary tract infection, blood transfusion, painful crisis, acute chest syndrome, vaso-occlusive crises).ConclusionAccording to the results of this meta-analysis, pregnancy in the SCD is associated with an increased risk of maternal outcomes, fetal outcomes, and morbidity among SCD patients with different genotypes. Pregnancy in sickle cell hemoglobinopathies needs careful multidisciplinary management and cautious caring so as to decrease maternal and fetal morbidity and mortality.  相似文献   
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