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BackgroundLow back pain is a highly prevalent and disabling musculoskeletal disorder. Physical activity is widely used as a prevention strategy for numerous musculoskeletal disorders; however, there is still conflicting evidence as to whether physical activity is a protective or risk factor for low back pain or whether activity levels differ between people with and without low back pain.ObjectiveTo investigate the association between low back pain and different types (occupational and leisure) and intensities (moderate and vigorous) of physical activity.MethodsThis is cross-sectional observational study. We included in this study a total of 1059 individuals recruited from a Spanish twin registry with data available on low back pain. Outcome: Self-reported leisure and occupational physical activity were the explanatory variables. The low back pain outcome used in this study was recurrent low back pain.ResultsOur results indicate that leisure physical activity is associated with a lower prevalence of recurrent low back pain. In contrast, occupational physical activity, such as carrying, lifting heavy weight while inclined, awkward postures (e.g. bending, twisting, squatting, and kneeling) are associated with a higher prevalence of recurrent low back pain. There was no statistically significant association between other occupational physical activities, such as sitting or standing, and low back pain.ConclusionLeisure and occupational physical activity are likely to have an opposed impact on low back pain. While leisure physical activity appears to be protective, occupational physical activity appears to be harmful to low back pain. Future longitudinal studies should assist in formulating guidelines addressing specific types and intensity of physical activity aimed at effectively preventing low back pain.  相似文献   
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Introduction: Patients with persistent atrial fibrillation (AF) have hemodynamic changes, which impair endothelial cell function resulting in decreased nitric oxide (NO) production. The aim of this work was to assess endothelial function in AF patients before and at various time points after cardioversion. Methods: Forty-two patients with AF and 21 normal and age-adjusted healthy controls were studied. Nitrites and nitrates (NO x ) and von Willebrand factor (vWf) concentrations were measured on blood samples taken just before cardioversion and over a 30 day period after the procedure. Results: Plasma levels of NO x in AF were significantly lower compared to healthy controls (p < 0.001), but after cardioversion gradually increased to approach to those of the healthy controls by the end of the first month of sustained sinus rhythm (p = 0.004). Interestingly plasma levels of NO x were negatively correlated to left atrial volume measured by ultrasonography (r = –0.34, p < 0.05). Plasma levels of vWf in AF patients were significantly higher compared to the healthy controls (p < 0.01) but with sustained sinus rhythm decreased (p = 0.02). Conclusion: The parallel normalization of the NO x titers and vWf levels suggests that vascular endothelial function improves after 30 days of normal sinus rhythm.  相似文献   
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Plasma cell leukemia (PCL) is a rare and aggressive plasma cell disorder, with poor outcome. Bortezomib‐based regimens (BBR) are highly effective in myeloma, but there is limited information about their efficacy and safety in PCL. Thus, we retrospectively collected data from 42 consecutive PCL patients (25 with primary PCL‐pPCL and 17 with secondary PCL‐sPCL) to explore the role of BBR in this entity. BBR were administered in 29 of 42 patients, while 6 of 25 patients with pPCL underwent autologous transplantation. Objective response (≥partial response) was significantly higher in patients treated with BBR versus conventional therapies (69% vs. 30.8%, P = 0.04); 27.5% of patients treated with BBR achieved at least very good partial response (vgPR). The highest ORR was observed in pPCL patients treated with BBR (88.9%; ≥vgPR: 33.3%). In BBR‐group, grade 3 of 4 hematological, neurological and renal toxicity and neutropenic infections were observed in 41.4%, 7%, 3.4%, and 31%, respectively. With a median follow‐up of 51 months, median overall survival (OS) for patients treated with BBR versus conventional therapies was 13 versus 2 months (P < 0.007). Median OS of patients with pPCL and sPCL treated with BBR was 18 and 7 months, respectively (P < 0.001). In the multivariate analysis normal PLTs, treatment with BBR and high quality response were the only powerful predictors for survival. Our study carrying the longest reported median follow‐up, demonstrated that treatment of PCL with BBR induces high response rates and prolongs survival over conventional therapies, regardless of additional autologous transplantation rescue or established high risk features, with manageable toxicity. Am. J. Hematol. 89:145–150, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
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Emerging evidence shows that severe coronavirus disease 2019 (COVID-19) can be complicated with coagulopathy, namely disseminated intravascular coagulation, which has a rather prothrombotic character with high risk of venous thromboembolism. The incidence of venous thromboembolism among COVID-19 patients in intensive care units appears to be somewhat higher compared to that reported in other studies including such patients with other disease conditions. D-dimer might help in early recognition of these high-risk patients and also predict outcome. Preliminary data show that in patients with severe COVID-19, anticoagulant therapy appears to be associated with lower mortality in the subpopulation meeting sepsis-induced coagulopathy criteria or with markedly elevated d-dimer. Recent recommendations suggest that all hospitalized COVID-19 patients should receive thromboprophylaxis, or full therapeutic-intensity anticoagulation if such an indication is present.  相似文献   
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Introduction

The aim of this systematic review was to assign levels of evidence (LOEs) to existing clinical articles related to the outcome of regenerative endodontic therapy and to evaluate the clinical and radiographic outcomes of this treatment modality.

Methods

Electronic search was executed in PubMed, Scopus, and Cochrane databases by using appropriate Medical Subject Headings terms covering the period from January 1993 to December 2013. Additional publications from hand-searching and reference section of each relevant article enriched the article list. The LOE of each article was assessed according to guidelines provided by the Oxford Centre of Evidence-Based Medicine. Quality assessment of the observational studies was executed by using the Newcastle-Ottawa scale.

Results

Fifty-one relevant publications were included in this review. There were 2 high-level cohort studies (LOE 2), 8 case series (LOE 4), and 41 case reports (LOE 5). The vast majority of the treated teeth in those publications showed resolution of clinical signs, symptoms, and periapical radiolucencies at follow-up period. Furthermore, the majority of treated teeth presented further increase in root length and root wall thickness and apical closure at the follow-up period. However, because of lack of sufficient high-level evidence it was not possible to answer totally the review question and determine definitely the outcome of regenerative endodontic therapy.

Conclusions

The lack of adequate high-level studies that could possibly strengthen the satisfactory current data and allow practicing more evidence-based dentistry constitutes a significant knowledge gap in the endodontic literature. However, the current best available evidence undeniably allows clinicians to provide this treatment modality safely to patients.  相似文献   
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