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排序方式: 共有10000条查询结果,搜索用时 93 毫秒
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Celia F Hybels Dan G Blazer Carl F Pieper Bruce M Burchett Judith C Hays Gerda G Fillenbaum Laura D Kubzansky Lisa F Berkman 《The American journal of geriatric psychiatry》2006,14(6):498-506
OBJECTIVE: Neighborhood sociodemographic characteristics may be important to the mental health of older adults who have decreased mobility and fewer resources. Our objective was to examine the association between neighborhood context and level of depressive symptomatology in older adults in a diverse geographic region of central North Carolina. METHODS: The sample included 2,998 adults 65 or older residing in 91 census tracts. Depressive symptoms were measured using the Center for Epidemiologic Studies-Depression scale (CES-D). Neighborhoods were characterized by five census-based characteristics: socioeconomic disadvantage, socioeconomic advantage, racial/ethnic heterogeneity, residential stability, and age structure. RESULTS: In ecologic level analyses, level of census tract socioeconomic disadvantage was associated with increased depressive symptoms. To determine whether neighborhood context was associated with depressive symptoms independently of individual characteristics, the authors used multilevel modeling. The authors examined the ability of each of five neighborhood (level 2) characteristics to predict a level 1 outcome (CES-D symptoms) controlling for the effects of individual (level 1) characteristics. Younger age, being widowed, lower income, and having some functional limitations were associated with increased depression symptoms conditional on census tract random effects. However, none of the neighborhood characteristics was significantly associated with depression symptoms, conditional on census tract random effects, either unadjusted or adjusted for individual characteristics. CONCLUSION: Any observed association between neighborhood sociodemographic characteristics and individual depressive symptoms in our sample may reflect the characteristics of the individuals who reside in the neighborhood rather than the neighborhood characteristics themselves. The use of multilevel modeling is important to separate these effects. 相似文献
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C Edward Hoffler Kurt D Hankenson Joshua D Miller Sukhinderdeep K Bilkhu Steven A Goldstein 《Journal of orthopaedic research》2006,24(8):1687-1698
To understand in situ behavior of osteocytes, we characterized a model of osteocytes in their native bone matrix and demonstrated real-time biologic activity of osteocytes while bending the bone matrix. Using 43 male Sprague-Dawley rats, dumbbell-shaped explants were harvested from stainless steel femoral implants after 6-12 weeks and incubated in culture medium or fixed. Sixteen specimens were used to determine bone volume density (BV/TV), volumetric bone mineral density (BMD) and histology for different implantation periods. Osteocyte viability was evaluated by L-lactate dehydrogenase (LDH) activity in 12 cultured explants. Confocal microscopy was used to assess tracer diffusion in three explants and changes in osteocyte pH of a mechanically loaded explant. From 6 to 12 weeks, explant BV/TV and volumetric BMD trended up 92.5% and 101%, respectively. They were significantly and highly correlated. Tissues were uniformly intramembranous and all bone cell types were present. Explants maintained LDH activity through culture day 8. Diffusion at 200 microM was limited to 1,209 Da. Explants appeared capable of reproducing complex bone biology. This model may be useful in understanding osteocyte mechanotransduction in the context of a physiologically relevant bone matrix. 相似文献
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Sales Anne Smith Jeffrey Curran Geoffrey Kochevar Laura 《Journal of general internal medicine》2006,21(2):S43-S49
This paper presents a case for careful consideration of theory in planning to implement evidence-based practices into clinical care. As described, theory should be tightly linked to strategic planning through careful choice or creation of an implementation framework. Strategies should be linked to specific interventions and/or intervention components to be implemented, and the choice of tools should match the interventions and overall strategy, linking back to the original theory and framework. The thesis advanced is that in most studies where there is an attempt to implement planned change in clinical processes, theory is used loosely. An example of linking theory to intervention design is presented from a Mental Health Quality Enhancement Research Initiative effort to increase appropriate use of antipsychotic medication among patients with schizophrenia in the Veterans Health Administration. 相似文献
67.
Changes on serial assessments of brain MRI lesion load are used for monitoring therapeutic efficacy in patients with multiple
sclerosis (MS). We assessed the accuracy and reliability of conventional spin-echo (CSE) and fast spin-echo (FSE) sequences
for measurement of lesion volume using a semiautomated contour technique. Cranial CSE and FSE examinations of 18 patients
with secondary progressive MS were studied. The mean lesion load was slightly higher with the CSE sequence (p = 0.002). Intraobserver
variability was significantly higher for FSE than for CSE, according to both the coefficient of variation between two measurements
(mean 2.48 % and 1.35 % respectively, p < 0.05) and back-transformed 95 % limits of agreement (1.005–1.060 for FSE; 0.988–1.019
for CSE). Although FSE sequences are quicker and the total lesion volume measurements are similar to those obtained with CSE,
the poorer reproducibility raises doubts about the use of FSE to replace CSE in clinical trials.
Received: 26 March 1996 Accepted: 4 April 1996 相似文献
68.
Effects of hypothermia on testicular ischemia 总被引:14,自引:0,他引:14
The ischemic effects of prolonged testicular torsion have been well documented; however, prevention or arrest of the damaging effects of prolonged ischemia has been incompletely studied. Two groups of Sprague-Dawley rats were subjected to varying lengths of bilateral testicular ischemia. Group I underwent normothermic ischemia for two, four, and six hours. Likewise, Group II underwent similar time periods of ischemia, however, after thirty minutes of normothermic ischemia the scrotum of each animal was placed into an ice bath maintained at 4C. Two weeks postoperatively, bilateral orchiectomy was performed. Histology of the testes of the two groups was compared. Neither group revealed significant destruction of the germinal epithelium after two hours of ischemia. Group I revealed only 25% preservation of the germinal epithelium at four hours and only 8% preservation at six hours of ischemia. In contrast, Group II which received ice showed 90% preservation of germinal epithelium at four hours and 85% preservation at six hours of ischemia. We conclude that external ice application significantly preserves seminiferous tubules at four and six hours of ischemic injury in the rat testicle. 相似文献
69.
K Y Mumcuoglu J Miller R Gofin B Adler F Ben-Ishai R Almog D Kafka S Klaus 《Public health reviews》1990,18(4):335-344
BACKGROUND: The aim was to determine the influence of the socioeconomic status of the family and the hygienic practices in the home on the prevalence of head lice infestation in children. METHODS: The study was carried out by analyzing the answers to a standardized epidemiological questionnaire given to parents of school children aged 4-17 in Bet Shemesh, a medium-sized urban town 25 km from Jerusalem. RESULTS: Of 3,000 questionnaires distributed, 958 (31.9%) were completed and returned. The majority of the children (72.4%) had been previously infested with lice. Half of them had other family members, mainly brothers and sisters, who had been infested in the past with lice. In 97.5% of the families the mother was responsible for examining the children for lice, and for carrying out treatment when infestation was present. An association was found between presence of lice infestation and mother's education, age of child, and frequency of shampooing, combing, and examination for lice. There was no association between infestation rates and mother's country of origin, crowding in the home, and the sharing of combs, brushes, hats, scarves, towels, and clothes. CONCLUSIONS: There is evidence that the incidence of lice infestation depends on the hygienic practices in the home rather than on the socioeconomic status of the family or sharing of personal articles among family members. 相似文献
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