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991.
992.
This prospective study was completed to establish results obtained using a static splinting regimen as an alternative to the dynamic extension splint. Fifteen patients with rheumatoid arthritis, who had undergone metacarpophalangeal (MCP) joint arthroplasties and a postoperative rehabilitation program of alternating MCP joint flexion and extension static splints, were assessed pre-operatively and reviewed postoperatively. Total active arc of MCP joint motion and ulnar deviation were measured, and an activities-of-daily-living questionnaire was completed by each patient at 19 months (mean) postoperatively. Mean total active arc of MCP joint motion showed statistical improvement from 21.6 degrees (range, 5 degrees-60 degrees) pre-operatively to 47.2 degrees (range, 15 degrees-84 degrees) postoperatively. The little finger gained the most improvement, with a 50.2 degree arc, showing that this regimen does not compromise flexion gains at this joint. Ulnar deviation improved from a mean of 30.4 degrees (range, 5 degrees-65 degrees) pre-operatively to 9.7 degrees (range, 0 degrees-30 degrees) postoperatively. These initial results reinforce the clinical impression that this alternating static splint regimen can be used as an effective alternative to the dynamic extension splint.  相似文献   
993.
Simultaneous changes in visual stimulus attributes (such as motion or color) are often perceived to occur at different times, a fact usually attributed to differences in neural processing times of those attributes. However, other studies suggest that perceptual misalignments are not due to stimulus attributes, but to the type of change, first- or second-order. To test whether this idea generalizes across modalities, we studied perceptual synchrony of acoustic and of audiovisual cross-modal stimuli, which varied in a first- or second-order fashion. First-order changes were abrupt changes in tone intensity or frequency (auditory), or spatial position (visual), while second-order changes were an inversion of the direction of change, such as a turning point when a rising tone starts falling or a translating visual blob reverses. For both pure acoustic and cross-modal stimuli, first-order changes were systematically perceived before second-order changes. However, when both changes were first-order, or both were second-order, little or no difference in perceptual delay was found between them, regardless of attribute or modality. This shows that the type of attribute change, as well as latency differences, is a strong determinant of subjective temporal alignments. We also performed an analysis of reaction times (RTs) to the first- and second-order attribute changes used in these temporal alignment experiments. RT differences between these stimuli did not correspond with our temporal alignment data, suggesting that subjective alignments cannot be accounted for by a simple latency-based explanation.  相似文献   
994.
This paper investigated whether smoking and short stature in adulthood were independent risk factors for hearing loss. We reanalyzed data from the Danish Work Environment Cohort Study (an existing cohort study), on prevalence of self-reported hearing loss among 7,221 employees and on five-year incidence among 4,610 employees. We found that smoking predicted hearing loss incidence and prevalence. Smoking did not predict incidence at noise exposure during half or more of a worker's hours. Very short stature predicted prevalence in the total adult population only weakly, but strongly among employees born before 1951. These prospective findings indicate that smoking is an independent risk factor for incidence of hearing loss. Very short stature predicted prevalence of hearing loss only in a subpopulation.  相似文献   
995.
Allen MR  Burr DB 《BONE》2005,36(2):311-316
Periosteal expansion enhances bone strength and is controlled by osteogenic cells of the periosteum. The extent of cellular periosteum at the human femoral neck, a clinically relevant site, is unclear. This study was designed to histologically evaluate the human femoral neck periosteal surface. Femoral neck samples from 11 male and female cadavers (ages 34-88) were histologically assessed and four periosteal surface classifications (cellular periosteum, mineralizing periosteum, cartilage, and mineralizing cartilage) were quantified. Femoral mid-diaphysis samples from the same cadavers were used as within-specimen controls. The femoral neck surface had significantly less (P<0.05) cellular periosteum (18.4+/-9.7%) compared to the femoral diaphysis (59.2+/-13.8%). A significant amount of the femoral neck surface was covered by mineralizing periosteal tissue (20-70%). These data may provide an alternate explanation for the apparent femoral neck periosteal expansion with age and suggest the efficiency of interventions that stimulate periosteal expansion may be reduced, albeit still possible, at the femoral neck of humans.  相似文献   
996.
997.
INTRODUCTION: Based on the clinical history, paroxysmal atrial fibrillation (PAF) may be classified as vagotonic, adrenergic, or random. It is unclear whether pulmonary vein (PV) isolation is equally effective for these types of PAF. METHODS AND RESULTS: Segmental ostial ablation to isolate the PVs was performed in 188 consecutive patients (mean age 53 +/- 12 years) with PAF. Based on the clinical history, PAF was classified as random in 136 patients (72%), adrenergic in 30 (16%), and vagotonic in 22 (12%). Three or four PVs were targeted for isolation in all patients, and successful isolation was achieved in 96% of targeted PVs. At 1-year follow-up, 69% of patients with random AF, 83% of patients with adrenergic AF, and 50% of patients with vagotonic AF were free from recurrent episodes of AF in the absence of any antiarrhythmic drug therapy. Vagotonic AF was an independent clinical predictor of recurrent AF (P = 0.03). CONCLUSION: PV isolation has a lower efficacy in patients with vagotonic PAF than in patients with adrenergic or random episodes of PAF, suggesting that the PVs less often play an important role in vagotonic PAF.  相似文献   
998.
Background: Recent data demonstrate that moderate consumption of alcohol may be beneficial to cognition. DESIGN: Longitudinal growth curve analyses controlling for variables related to cognition were used to examine the relationship between alcohol consumption, ethnic differences, gender, and cognition over a 4-year-follow-up period. Sample: The sample included 1,836 Japanese American and 2,581 Non-Hispanic White American community-dwelling adults age 65 and older who were cognitively intact at baseline and participated in at least one follow-up examination. Measurement: Cognitive performance was measured using the Cognitive Abilities Screening Instrument (CASI) and reaction time. RESULTS: Current drinkers scored significantly higher on CASI over time than past drinkers or abstainers. The same association between alcohol and CASI was observed in both genders and both ethnic groups. CONCLUSION: This study provides support regarding the potential beneficial outcomes associated with alcohol consumption and cognition and that these benefits were not modified by gender or ethnicity.  相似文献   
999.
Risk factors predicting hip pain in a 5-year prospective cohort study   总被引:1,自引:0,他引:1  
OBJECTIVES: The aim of the study was to identify and quantify risk factors for hip pain. METHODS: A representative sample of 5001 Danish men and women aged 18-65 years in 1990 were interviewed about occupational exposures (response rate 90%); 5 years later they were reinterviewed about hip pain (response rate 86%). Logistic regression with forced entry of all the independent variables was used to estimate the odds ratios for the possible risk factors. The impact of the various predictors was assessed through the calculation of population etiologic fractions. RESULTS: A double risk of hip pain was found for the women as compared with the men [odds ratio (OR) 2.28, 95% confidence interval (95% CI) 1.68-3.09]. The risk increased with body mass index. Whole-body vibration (OR 1.86, 95% CI 1.09-2.71) and physically demanding work (OR 1.83, 95% CI 1.23-2.71) were strong predictors of hip pain, while a squatting work posture was protective (OR 0.64, 95% CI 0.42-0.98). The impact of the statistically significant predictors (the etiologic fractions) was as follows: 0.49 for body mass index, 0.05 for whole body vibration, 0.10 for physically demanding work, and 0.32 for squatting (preventive). CONCLUSIONS: Female gender, age, high body mass index, whole-body vibration, and physically demanding work are significant risk factors for hip pain.  相似文献   
1000.
OBJECTIVE: To see whether mortality among men with angina can be reduced by dietary advice. DESIGN: A randomized controlled factorial trial. SETTING: Male patients of general practitioners in south Wales. SUBJECTS: A total of 3114 men under 70 y of age with angina. INTERVENTIONS: Subjects were randomly allocated to four groups: (1) advised to eat two portions of oily fish each week, or to take three fish oil capsules daily; (2) advised to eat more fruit, vegetables and oats; (3) given both the above types of advice; and (4) given no specific dietary advice. Mortality was ascertained after 3-9 y. RESULTS: Compliance was better with the fish advice than with the fruit advice. All-cause mortality was not reduced by either form of advice, and no other effects were attributable to fruit advice. Risk of cardiac death was higher among subjects advised to take oily fish than among those not so advised; the adjusted hazard ratio was 1.26 (95% confidence interval 1.00, 1.58; P=0.047), and even greater for sudden cardiac death (1.54; 95% CI 1.06, 2.23; P=0.025). The excess risk was largely located among the subgroup given fish oil capsules. There was no evidence that it was due to interactions with medication. CONCLUSIONS: Advice to eat more fruit was poorly complied with and had no detectable effect on mortality. Men advised to eat oily fish, and particularly those supplied with fish oil capsules, had a higher risk of cardiac death. This result is unexplained; it may arise from risk compensation or some other effect on patients' or doctors' behaviour.  相似文献   
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