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OBJECTIVES: To compare the effect of a neuromuscular training program and a basic exercise program on postural control in figure skaters. DESIGN: Two groups; parallel design; prospective, randomized controlled trial. SETTING: Postural control laboratory, arenas, September 2001 to December 2002. PARTICIPANTS: Forty-four young, healthy figure skaters (18 years +/- 3 years). INTERVENTIONS: Participants were randomly assigned to receive a neuromuscular training program (n = 22) or a basic exercise training program (n = 22). Both programs were completed 3 times per week for 4 weeks, and each session was supervised. MAIN OUTCOME MEASUREMENTS: Participants completed baseline and postintervention measures of postural control on a force plate. Postural control was quantified as the center of pressure (CoP) path length during tests of single-limb standing balance that mimicked figure skating skills and challenged the postural control system to varying degrees. The primary outcome measure was the CoP path length observed during a landing jump test completed with eyes closed. RESULTS: The post intervention CoP path lengths during the more challenging tests were significantly (P < 0.05) lower (indicating better postural control) for the neuromuscular trained group than for the basic exercise-trained group. For the landing jump test completed with eyes closed, the percent improvement in the neuromuscular trained group was significantly greater (mean = 21.0 +/- 22.0%) than the basic exercise trained group (mean = -4.9 +/- 24.9%; P < 0.05). The magnitude of improvement in the neuromuscular-trained group ranged from approximately 1% to 21%, depending on the specific postural control test used. CONCLUSIONS: The results suggest that off-ice neuromuscular training can significantly improve postural control in figure skaters, whereas basic exercise training does not.  相似文献   
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This study was undertaken to resolve existing controversies with respect to the detection of IgA HIV-1-specific mucosal antibodies in infected individuals. External secretions, including tears, nasal, rectal, and vaginal washes, saliva, semen, urine, and sera were obtained from 50 HIV-1-infected individuals and 20 controls using collection procedures that minimize the irritation of mucosal surfaces. Levels of total and antigen (gp120 and gp160)-specific antibodies of the IgG and IgA isotypes were measured by assays that proved reliable in a large multicenter study: quantitative ELISA and chemiluminescence-enhanced Western blot analyses. Although the levels of total IgG and IgA were increased or remained unchanged in body fluids of HIV-1-infected individuals as compared to the controls, HIV-1-specific IgA antibodies were either absent or present at low levels even in secretions with characteristically high relative contents of total IgA vs. IgG (saliva, tears, and rectal and nasal washes). In these secretions, HIV-1-specific IgG antibodies dominated. In assessing levels and frequency of detection of IgG antibodies, both female and male genital tract secretions, urine, and nasal wash were preferable to parotid saliva and especially to rectal wash. External secretions contained IgG antibodies to gp160> gp120> gp41 and p24; when present, IgA antibodies were predominantly directed at gp160. Analyses of peripheral blood antibody-secreting cells (ASC) isolated from the same individuals paralleled these serological findings: gp160-specific IgG-secreting ASC were dominant. Therefore, in striking contrast to other mucosally encountered microbial infections, HIV-1 does not induce vigorous specific IgA responses in any body fluid examined or in ASC in peripheral blood.  相似文献   
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Objective: This study examines (1) whether youth and their caregivers have different preferences for asthma education video topics and (2) if education topic preferences vary by youth and caregiver sociodemographic characteristics. Methods: Youth (n?=?83) ages 7–17 years with persistent asthma and their caregivers were recruited at two pediatric practices in North Carolina. Sociodemographic information and youth and caregiver preferences for nine asthma video education topics were collected during in-person interviews. Bonferroni-corrected Chi-square or McNemar tests (α?=?0.0056) were used to compare youth and caregivers differences in topic preferences and topic preferences by youth and caregiver sociodemographic characteristics, including gender, race, ethnicity, and age. Results: Youth were primarily male (52%) and from low-income families (74%; caregiver annual income less than $30 000) and many were Hispanic (45%). Youth and parents expressed the most interest in the following two topics: “how to deal with triggers” (90% and 95%, respectively) and “how to keep asthma under control” (87% and 96%, respectively). Caregivers and children were discordant for two topics: “the difference between a rescue and controller medicine” and “how to [help your child] talk to your [his/her] friends about asthma.” No differences were found between youth and caregiver sociodemographic characteristics and video topic preferences. Conclusions: Youth with persistent asthma and their caregivers differed in their asthma education topic preferences, but preferences did not vary by caregiver or youth sociodemographic characteristics. Studies examining the effectiveness of interventions tailored to differences in educational preferences of youth with asthma and their caregivers are needed.  相似文献   
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OBJECTIVE: To investigate the dimensionality and construct validity of the Fugl-Meyer Assessment of the upper extremity by using Rasch analysis. DESIGN: Secondary analysis of pooled data from 2 existing datasets: a randomized therapeutic exercise clinical trial and a cohort longitudinal study of stroke recovery. SETTING: University research center. PARTICIPANTS: A total of 512 subjects, ages 69.8+/-11.1 years, who were 0 to 145 days poststroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Dimensionality was examined with principal components analysis and Rasch item-fit statistics. The Rasch-derived item hierarchy was examined for consistency with the expected course of poststroke upper-extremity recovery suggested by the reflex-hierarchical conceptual model underlying the assessment. RESULTS: Factor loadings and item infit statistics suggested that the 3 reflex items were empirically disconnected from other assessment items. The reflex items were removed. The modified 30-item assessment showed a unidimensional structure. The Rasch-item-difficulty order was not consistent with the expected item order. CONCLUSIONS: The items testing resting-state reflexes may threaten the assessment's dimensionality. With reflex items removed, the assessment is a unidimensional measure of volitional movement. The Rasch-generated item-difficulty order challenges the hierarchical structure implied by the instrument's underlying conceptual framework.  相似文献   
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Background: The management of stage III breast cancer is challenging; it often includes multimodal treatment with systemic therapy and/or radiation therapy and surgery. Immediate breast reconstruction has not traditionally been performed in these patients. We review the results of immediate transverse rectus abdominis musculocutaneous (TRAM) flap in 21 patients treated for stage III breast cancer. Methods: Data have been collected retrospectively on 21 patients diagnosed with stage III breast cancer between 1987 and 1994. All patients had mastectomy and immediate TRAM reconstruction. Thirteen patients received primary systemic therapy, 10 patients received postoperative consolidation radiotherapy to the operative site, and 3 patients received preoperative radiation. Results: Mean follow-up for the group was 26 months. Two patients died with disseminated disease: neither of them developed local disease recurrence in the operative site; 82% of the patients followed for at least two years are free of disease. Sixty-two percent of the patients received preoperative chemotherapy, the remaining patients received postoperative multiagent chemotherapy and/or radiation therapy. Two of the patients received autologous bone marrow transplants after their adjuvant therapy. Ten patients had postoperative radiotherapy for consolidation; three patients received preoperative radiation. Conclusions: Immediate TRAM reconstruction for stage III breast cancer is not associated with a delay in adjuvant therapy or an increased risk of local relapse. It facilitates wide resection of involved skin without skin grafting. Radiation therapy can be delivered to the reconstructed breast when indicated without difficulty. Breast reconstruction facilitates surgical resection of stage III breast cancer with primary closure and should be considered if the patient desires immediate breast reconstruction.Results of this study were presented at the 48th Annual Cancer Symposium of The Society of Surgical Oncology, Boston, Massachusetts, March 23–26, 1995.  相似文献   
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