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Women participating in studies in Brazil (n = 695) and South Africa (n = 230) performed rapid point-of-care tests for Trichomonas vaginalis on self-collected vaginal swabs. Using PCR as the gold standard, rapid self-testing achieved high specificity (99.1%; 95% confidence interval [CI], 98.2 to 99.6%) and moderate sensitivity (76.7%; 95% CI, 61.4 to 88.2%). These tests may be considered an alternative to syndromic management in resource-poor settings.  相似文献   
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Purpose This study was designed to develop and test the validity and reliability of the Constipation Severity Instrument. Methods Scale development was conducted in two stages: 1) 74 items were generated through a literature review and focus groups of constipated patients and medical providers; and 2) a preliminary instrument was administered to 191 constipated patients and 103 healthy volunteers. Test-retest reliability of the constipated group was assessed (N = 90). Content, convergent, divergent, and discriminant validity were evaluated by using other validated measures by performing one-way analysis of variance and Pearson correlations. Results Exploratory and confirmatory factor analysis revealed three subscales: obstructive defecation, colonic inertia, and pain. Internal consistency (α = 0.88–0.91) and test-retest reliability (intraclass correlation coefficients = 0.84–0.91) were high for all subscales. Constipated patients were grouped by Rome II criteria: functional constipation (22 percent), pelvic floor dyssynergia (15 percent), constipation predominant irritable bowel syndrome (23 percent), and no specific criteria (40 percent). Those with constipation predominant irritable bowel syndrome or pelvic floor dyssynergia scored higher on the Obstructive Defecation and Colonic Inertia subscales than those with functional constipation or no specific criteria (P = 0.001–0.058). Subjects with functional constipation had much lower scores on the pain subscale than constipation predominant irritable bowel syndrome, functional constipation, or no specific criteria (P < 0.009).The Constipation Severity Instrument subscale and total score correlated very highly with the subscales and total score of the Patient Assessment of Constipation Symptom measure. The Constipation Severity Instrument subscales discriminated well between constipated patients and healthy volunteers (P < 0.001) and demonstrated excellent divergent validity. Higher Constipation Severity Instrument scores inversely correlated with general quality of life. Conclusions The Constipation Severity Instrument is a reliable and valid instrument for assessing constipated patients. Administration of the Constipation Severity Instrument to other constipated patients will further validate its use. Supported by the University of California San Francisco Hellman Family Award for Early Career Faculty. Read at the meeting of The American Society of Colon and Rectal Surgeons, St. Louis, Missouri, June 2 to 6, 2007. Reprints are not available.  相似文献   
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The application of resistance during the swing phase of locomotion is a viable approach to enhance activity in the rectus femoris (RF) in patients with neurological damage. Increased muscle activity is also accompanied by changes in joint angle and stride frequency, consequently influencing joint angular velocity, making it difficult to attribute neuromuscular changes in RF to resistance. Thus, the purpose of this study was to evaluate the effects of resistance on RF activity while constraining joint trajectories. Participants walked in three resistance conditions; 0 % (no resistance), 5 and 10 % of their maximum voluntary contraction (MVC). Visual and auditory biofeedback was provided to help participants maintain the same knee joint angle and stride frequency as during baseline walking. Lower limb joint trajectories and RF activity were recorded. Increasing the resistance, while keeping joint trajectories constant with biofeedback, independently enhanced swing phase RF activity. Therefore, the observed effects in RF are related to resistance, independent of any changes in joint angle. Considering resistance also affects stride frequency, a second experiment was conducted to evaluate the independent effects of resistance and stride frequency on RF activity. Participants walked in four combinations of resistance at 0 and 10 %MVC and natural and slow stride frequency conditions. We observed significant increases in RF activity with increased resistance and decreased stride frequency, confirming the independent contribution of resistance on RF activity as well as the independent effect of stride frequency. Resistance and stride frequency may be key parameters in gait rehabilitation strategies where either of these may be manipulated to enhance swing phase flexor muscle activity in order to maximize rehabilitation outcomes.  相似文献   
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Suppression of Aedes albopictus populations is a substantial challenge for mosquito control programs globally because juveniles of this species are found in numerous kinds of domestic artificial containers that are difficult to detect, access, and eliminate. We conducted a multi-year assessment of the effect of different interventions to control Ae. albopictus near the northernmost geographic boundary of the species in temperate North America and deployed an array of BG-Sentinel traps for adult surveillance. Here we present the results of a comparative examination of adult sex ratios in urban and suburban areas, shifts in sex ratios after control interventions, and a discussion of the critical drivers of population dynamics of Ae. albopictus in our area. We collected significantly more male mosquitoes in urban as compared to suburban areas in June through September, but not in May (p < 0.001). The higher number of male mosquitoes in urban areas could be attributed to a higher number of larval habitats within a closer proximity of the surveillance traps and the lower flight dispersal of males. Following application of adulticides in urban areas, Ae. albopictus male populations were reduced by 88% on average, which was higher than the 69% reduction in female populations. The higher reduction of male mosquitoes could be attributed to the smaller body mass of the males and their higher susceptibility to adulticides. The results of this study are directly relevant to the development of suitable control strategies that depend on manipulation of males, such as the sterile insect technique. The results could also be used to refine mosquito abatement by providing more accurate methods to determine the need and timing of vector control.  相似文献   
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