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1.
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   

2.
This study examined the temporal concordance between the onset of childhood anxiety disorders and the points of onset and ending of child sexual abuse (CSA). Sexually abused children (N = 158) were assessed with structured diagnostic interviews. Onset ages for lifetime prevalence anxiety disorders were combined and sequenced with the onset and ending of sexual abuse. Hazard rates were calculated. Departures from the overall linear hazard trajectory for onsets were modeled using piecewise growth curve analyses. Increases from the overall trajectory were found around the point of sexual abuse onset for most childhood anxiety disorders. Decreases were found around the ending of sexual abuse. The risk for developing new anxiety disorders after the onset of sexual abuse showed a positive dose-effect relation with abuse severity. The findings add support to the idea that CSA can have a direct link to childhood anxiety disorders, apart from confounded vulnerability factors, postabuse events, or stable family background factors. The findings are contrasted with those from cross-sectional partial correlation studies that have suggested that there is little direct connection between sexual abuse and mental health outcomes.  相似文献   
3.
Many behavioral, immunological, and physiological consequences of brief maternal separation in bonnet (Macaca radiata) and pigtail monkeys (Macaca nemistrina) have been documented. However, the impact of social separation on plasma cortisol and growth hormone is unknown for these particular species. In the present study, the behavioral and endocrinological consequences of a 2-week maternal separation in socially housed infant bonnet and pigtail monkeys were followed. In seven pairs (separated and matched control) of bonnet and six pairs of pigtail infants, plasma was obtained under baseline, separated, and reunion conditions twice weekly for the duration of the study. Blood samples were obtained from both infants of the pair in approximately 10 min. Plasma total cortisol, free cortisol, and growth hormone were measured in these samples. Focal animal behavioral observations were made on all subjects twice daily throughout the study period. In both species, total cortisol and free cortisol rose immediately following maternal separation in comparison to the matched nonseparated controls and returned to basal levels (e.g., that of matched non-separted controls) following reunion with the mother. In contrast, plasma growth hormone rose only in the pigtail infants over a time course that peaked around the time of reunion. Multiple regression techniques indicated for the first week of separation, in the separated but not control subjects, that mean plasma free and total cortisol was positively related to distress behaviors (vocalization and postural slouch) observed during this week and negatively related to social behaviors (play and proximity to others) noted during the same period. In contrast, plasma growth hormone was related to both species and sex of the subjects but unrelated to behavioral variables. © 1995 John Wiley & Sons, Inc.  相似文献   
4.
A series of 73 dibenzo[a,d]cycloalkenimines were synthesized and evaluated for their ability to displace (+)-10,11-dihydro-5-methyl-5H-dibenzo[a,d]cyclohepten-5,10-imine ([3H]-(+)-10) from its specific binding site on rat cortical membranes. A number of the more active compounds (Ki ranging from 0.006 to 0.21 microM) were evaluated for N-methyl-D-aspartate (NMDA) antagonist activity in the rat cortical slice (Kb ranging from 0.08 to 0.9 microM) and anticonvulsant activity in the mouse against NMDA induced convulsions. The ED50 values ranged from 0.22 to 7.76 mg/kg and correlated reasonably well with the Kb determination. In the dibenzo[a,d]cyclohepten-5,10-imine series, the (+)-5S,10R enantiomer displayed consistently higher levels of biological activity. While substitution at the 3-position of (+)-10 with electronegative atoms generally increased in vitro activity, a loss of potency relative to (+)-10 (MK-801) was observed in vivo for all of the compounds tested.  相似文献   
5.
Depression is under-detected, but is treatable and relapses can be prevented. Living with depression, whether acute or chronic, has consequences for quality of life, premature end of life, and productive life. Thoughtful and strategic quality improvement (QI) programs offer one avenue for improving the treatment of depression. Part I of this two-part series addresses improving the treatment of depression and employing disease management as a strategy to accomplish that aim. This article, part II, provides an overview of other QI initiatives that demonstrated treatment effectiveness for depression, including several used in managed care practice.Currently, the majority of QI programs for depression target adult patients; therefore, there are future challenges ahead as managed care attempts to address the needs of special populations, such as adolescents and older adults. Public education, professional education, and population-based interventions are also considerations as part of successful treatment. Although consumer-based interventions are typically more expensive, they may ultimately yield the best results for improving depression care for the consumer and payors based on available research. The success of a consumer-centric approach is highly reliant on the person’s engagement with QI programs, the treating clinician’s appreciation and support of such depression programs, and managed care’s response to solving quality problems using continuous monitoring, evaluation, feedback, system enhancements, and training. Models of collaboration between consumers and medical and behavioral health systems offer the most promising approaches to care improvements for patients with depression.  相似文献   
6.
Little attention has been directed toward inappropriate social and sexual approaches by patients with dementia diagnoses and organic disorders of the brain. A female student who approached patients who had dementia and organic brain disorders was frequently approached and touched in a sexual manner that was distressing to her and led her to believe that she was behaving in a manner that elicited these responses. It is recommended that students and volunteers be prepared for experience in settings with patients with these diagnoses through individual or group discussion, training and role playing as a way of enhancing their experiences and avoiding unnecessary feelings of guilt and embarrassment.  相似文献   
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A total of 317 unrelated Danish patients with insulin-dependent diabetes mellitus (IDDM) have been HLA-DR typed and the antigen and phenotype frequencies compared with those in 1177 unrelated Danish controls. The strong positive associations with DR3 and 4 and the strong negative one with DR2 were confirmed, and the remaining antigens showed a hierarchy from weakly positive to strongly negative associations: DRw9, w8, 1, 5, w6, 7. The study population included various special groups of patients selected in order to study heterogeneity: very early (less than 5 years) and very late (greater than 40 years) onset IDDM, pregnancy-induced IDDM, IDDM nephropathy, and long-term (greater than 40 years) survivors without complications. When comparing these groups, the following minor differences were seen: the DR3,4 phenotype is significantly (p = .02) more frequent in IDDM with onset before age 20 (35%) than in other cases (24%), and in familial IDDM (48%) than in other cases (28%); the frequency of the DR4 antigen was significantly (p = .008) more frequent in long-term survivors (86%) than in other patients (69%), while it was significantly (p = .02) less frequent in IDDM nephropathy (63%) than in long-term survivors. However, apart from the age-at-onset heterogeneity, which was suspected a priori, these differences may be due to chance, and the main conclusion of this study is that the HLA-DR associations in IDDM are indeed extraordinarily homogeneous irrespective of the clinical characteristics at onset and course of the disease.  相似文献   
10.
The present study sought to determine whether acoustic properties of the auditory conditioned stimulus (CS) or the use of a discrimination learning procedure would alter the emergence of eyeblink conditioning between postnatal Days 17 and 24 (Days 17–24) in the rat. In Experiment 1, we employed a 3 × 2 × 2 factorial design, involving pitch of the auditory CS (2.8, 5.0, and 9.0 kHz), training condition (paired vs. unpaired), and age (Days 17 or 24). Associative learning was evident at all tone frequencies on Day 24, but increased across frequencies on Day 17, although large age differences in conditioning remained at all tone frequencies. In Experiment 2, rat pups were trained to discriminate 2.8 versus 9.0-kHz tones on Day 17 or Day 24. Eyeblink conditioning increased with tone frequency on Day 24 but discriminative conditioning failed to appear on Day 17. These findings are discussed in relation to the role of auditory system maturation in the ontogeny of eyeblink conditioning. © 1995 Johnv Wiley & Sons, Inc.  相似文献   
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