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991.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Ligninolytic bacteria are considered a major source of ligninolytic enzymes, which are widely used in a...  相似文献   
992.
Abdominal Radiology - Prior iterative reconstruction (PIR) uses spatial information from one phase of enhancement to reduce image noise in other phases. We sought to determine if PIR could reduce...  相似文献   
993.
With the aging of the population, vision (VL), hearing (HL), and dual-sensory (DSL, concurrent VL and HL) loss will likely constitute important public health challenges. Walking speed is an indicator of functional status and is associated with mortality. Using the Health and Retirement Study, a nationally representative U.S. cohort, we analyzed the longitudinal relationship between sensory loss and walking speed. In multivariable mixed effects linear models, baseline walking speed was slower by 0.05 m/s (95% confidence interval [CI] = 0.04–0.07) for VL, 0.02 (95% CI = 0.003–0.03) for HL, and 0.07 (95% CI = 0.05–0.08) for DSL compared with those without sensory loss. Similar annual declines in walking speeds occurred in all groups. In time-to-event analyses, the risk of incident slow walking speed (walking speed < 0.6 m/s) was 43% (95% CI = 25–65%), 29% (95% CI = 13–48%), and 35% (95% CI = 13–61%) higher among those with VL, HL, and DSL respectively, relative to those without sensory loss. The risk of incident very slow walking speed (walking speed < 0.4 m/s) was significantly higher among those with HL and DSL relative to those without sensory loss, and significantly higher among those with DSL relative to those with VL or HL alone. Addressing sensory loss and teaching compensatory strategies may help mitigate the effect of sensory loss on walking speed.  相似文献   
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Resistant starch (RS), fed as high amylose maize starch (HAMS) or butyrylated HAMS (HAMSB), opposes dietary protein-induced colonocyte DNA damage in rats. In this study, rats were fed Western-type diets moderate in fat (19%) and protein (20%) containing digestible starches [low amylose maize starch (LAMS) or low amylose whole wheat (LAW)] or RS [HAMS, HAMSB, or a whole high amylose wheat (HAW) generated by RNA interference] for 11 wk (n = 10/group). A control diet included 7% fat, 13% protein, and LAMS. Colonocyte DNA single-strand breaks (SSB) were significantly higher (by 70%) in rats fed the Western diet containing LAMS relative to controls. Dietary HAW, HAMS, and HAMSB opposed this effect while raising digesta levels of SCFA and lowering ammonia and phenol levels. SSB correlated inversely with total large bowel SCFA, including colonic butyrate concentration (R(2) = 0.40; P = 0.009), and positively with colonic ammonia concentration (R(2) = 0.40; P = 0.014). Analysis of gut microbiota populations using a phylogenetic microarray revealed profiles that fell into 3 distinct groups: control and LAMS; HAMS and HAMSB; and LAW and HAW. The expression of colonic genes associated with the maintenance of genomic integrity (notably Mdm2, Top1, Msh3, Ung, Rere, Cebpa, Gmnn, and Parg) was altered and varied with RS source. HAW is as effective as HAMS and HAMSB in opposing diet-induced colonic DNA damage in rats, but their effects on the large bowel microbiota and colonocyte gene expression differ, possibly due to the presence of other fiber components in HAW.  相似文献   
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Objectives. We systematically reviewed the literature on the impact of returning to work on health among working-aged adults.Methods. We searched 6 electronic databases in 2005. We selected longitudinal studies that documented a transition from unemployment to employment and included a comparison group. Two reviewers independently appraised the retrieved literature for potential relevance and methodological quality.Results. Eighteen studies met our inclusion criteria, including 1 randomized controlled trial. Fifteen studies revealed a beneficial effect of returning to work on health, either demonstrating a significant improvement in health after reemployment or a significant decline in health attributed to continued unemployment. We also found evidence for health selection, suggesting that poor health interferes with people’s ability to go back to work. Some evidence suggested that earlier reemployment may be associated with better health.Conclusions. Beneficial health effects of returning to work have been documented in a variety of populations, times, and settings. Return-to-work programs may improve not only financial situations but also health.The negative effects of unemployment on health have been well documented.1–5 Several longitudinal studies have shown a relationship between unemployment and mortality.6–11 The population health consequences arising from periods of economic decline have engendered some controversy,12 but the evidence on the association between unemployment and poor health is sufficiently robust to suggest causality.13,14 However, most studies examine the detrimental effects of negative social experiences rather than the constructive effects of positive events. As a result, research into the relationship between employment status and health has predominantly focused on the effects of job loss and unemployment rather than on the health impact of returning to work.The question of whether social factors are a cause or consequence of disease and illness is often framed in the context of the debate over social selection versus social causation and remains a source of controversy.15–19 The social causation hypothesis suggests that employment leads to health benefits, and the social selection hypothesis proposes that health is a necessary condition for employment. Research suggests that the causation effect may be of greater importance than the selection effect, but both mechanisms may interact and reinforce each other.15,18 We conducted a systematic review of the research literature on the impact of returning to work on physical and mental health in working-aged adults.  相似文献   
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Aim:

To evaluate mid-term outcome in patients who underwent arthroscopic subacromial decompression (ASD) for shoulder impingement syndrome with intact and partially torn rotator cuffs.

Materials and Methods:

A total of 80 consecutive patients (83 shoulders) who underwent ASD for impingement syndrome between 2003 and 2006 were analyzed. Mean age was 57.1 years. Patients’ self-reported Oxford Shoulder Score (OSS) for pain was collected prospectively and was used as an instrument to measure surgical outcome.

Results:

The mean initial and final OSS for patients with an intact rotator cuff was 26.1 and 40.3, respectively, at a mean follow up of 71.9 months (nearly 7 years). The mean initial and final OSS for patients with a partially torn articular sided tear was 22.6 and 41.9, respectively, at mean follow up of 70.7 months. Both groups showed significant sustained improvement (P < 0.0001). The mean improvement of OSS following ASD was statistically greater (P < 0.03) for partially torn rotator cuff group (19.3 points) as compared to those with normal rotator cuff (14.2 points).

Conclusion:

Patients with dual pathology (partial rotator cuff tear and impingement) appreciated a significantly greater improvement following ASD compared to those with impingement alone. Both groups of patients had a similar final outcome at a mid-term follow up.

Level of Evidence:

IV, retrospective study on consecutive series of patients.  相似文献   
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