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We previously reported that in p53 + / − mice that had been given a whole-body dose of 3 Gy at 8 weeks of age, p53-dependent delayed effects of radiation, as manifested in T-cell receptor (TCR) variant fractions (VF) instability in mouse splenocytes, were biphasic, namely, induction of TCR-VF mutation reappeared at 44 weeks. The manifestation of the delayed effects and the measures of biological markers varied according to the timing of irradiation. We also reported that the decrease in function of the p53 gene was related to the effects of a delayed mutation. In the present study, we investigated the functions and mutations of the p53 gene in old age for p53 + / − mice following irradiation at various ages. p53 + / − mice were given a whole-body dose of 3 Gy at 8, 28 or 40 weeks of age. There were significant differences for all variables tested at 8 weeks of age. This was similarly the case for mice irradiated at 28 weeks of age, in which there were also significant differences in TCR VF and the percentage of apoptosis. In mice irradiated at 40 weeks of age, there were significant differences for all considered variables except for the p53 allele. We demonstrated that the different patterns of delayed mutation of the p53 gene at 56 weeks of age depended on the age at which mice had undergone 3-Gy whole-body irradiation. Our conclusions are limited to variation in p53-dependent delayed effects according to the time of irradiation.  相似文献   
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While high intensity exercise is associated with improvement of both motor and non-motor symptoms in Parkinson’s disease (PD), there is limited evidence on its impact on sleep disturbances in PD. This scoping review aims to provide a preliminary statement of the potential size and scope of available evidence for the interaction between exercise and sleep in people with PD. Research to date on non-motor symptoms of PD is broad, with scarce information regarding specific effects of exercise on sleep. A systematic literature search was conducted through three phases. Fifteen articles met the inclusion criteria for this study. Resistive exercise and multimodal exercise programs were frequently studied and found to improve sleep and decrease sleep-related disorders. These findings suggest that exercise programs may improve sleep and other non-motor symptoms of PD. The research was inconclusive when comparing the effects of high and low intensity exercises. Further research on the interaction between exercise and sleep in PD may have implications for rehabilitative therapy interventions.  相似文献   
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Determinants of tuberculosis (TB) syringomyelia, its management options and outcomes are still under investigation. The aim of this study is to present a case of TB syringomyelia with markedly improved symptoms status-post surgery and to understand the clinical characteristics and outcomes of 33 TB syringomyelia cases reported in the literature. Specifically, we examined the differences between patients who were managed medically and those who underwent surgical intervention. Inclusion criteria for the cases were (1) syringomyelia caused by TB infection rather than co-occurrence of these conditions, (2) management protocol described, and (3) post-treatment outcome described. The median age was 30 years (interquartile range (IQR): 23–40) with 55% males. The median time between TB onset to syringomyelia diagnosis was 2 years. Nineteen patients were surgically treated, 11 were medically treated, and 3 received no treatment. Twenty-one patients showed improvement in at least one prior symptom, but no patient experienced a full recovery. Those that underwent surgical intervention were more likely to have TB meningitis (95% vs. 64%, p < 0.05) upon initial TB presentation and have a greater interval between TB onset and syringomyelia presentation (median of 2.6 vs. 0.33 years, ns). A greater proportion of the surgically managed patients experienced improvement in any symptom (74% vs. 45%, ns). Future case-controlled studies with larger sample sizes are required to validate and further understand the outcomes of surgically-managed TB syringomyelia.  相似文献   
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目的验证和探讨在高能同步辐射光源辐射屏蔽计算中半经验公式和蒙特卡罗模拟方法的一致性和适用性。方法分别采用半经验公式和蒙特卡罗模拟独立计算单电子打靶时屏蔽体外产生的周围剂量当量。结果Jenkins半经验公式计算结果与蒙特卡罗模拟结果比值范围为111%~153%,Sakano半经验公式计算结果与蒙特卡罗模拟结果比值为201%。结论对单一屏蔽材料,半经验公式可简单、保守地完成对高能电子加速器的屏蔽计算。对于多种屏蔽材料,宜采用蒙特卡罗模拟方法。  相似文献   
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BackgroundRepetitive microtrauma can result in a hypertrophied ATFL. Previous studies have found that the anterior talofibular ligament thickness (ATFLT) is correlated with lateral ankle sprains, ligament injuries and chronic stroke in patients, and thickened anterior talofibular ligament (ATFL) has been considered to be a major morphologic parameter of hypertrophied ATFL. However, hypertrophy is different from thickness. Thus, we devised the anterior talofibular ligament area (ATFLA) as a new morphological parameter to evaluate the hypertrophy of the whole ATFL.MethodsATFL samples were collected from 53 patients with sprain group and from 50 control subjects who underwent magnetic resonance imaging (MRI) of the ankle and revealed no evidence of lateral ankle injury. Axial T1-weighted MRI images were collected at the ankle level from all subjects. We measured the ATFLA and ATFLT at the anterior margin of the fibular malleolus to the talus bone on the MRI using a picture archiving and communications system. The ATFLA was measured as the whole cross-sectional ligament area of the ATFL that was most hypertrophied in the axial MR images. The ATFLT was measured as the thickest point between the lateral malleolus and the talus of the ankle.ResultsThe average ATFLA was 25.0 ± 6.0 mm2 in the control group and 47.1 ± 10.4 mm2 in the sprain group. The average ATFLT was 2.3 ± 0.6 mm in the control group and 3.8 ± 0.6 mm in the hypertrophied group. Patients in sprain group had significantly greater ATFLA (p < 0.001) and ATFLT (p < 0.001) than the control subjects. A Receiver Operator Characteristics curve analysis showed that the best cut-off point of the ATFLA was 34.8 mm2, with 94.3% sensitivity, 94.0% specificity, and an AUC of 0.97 (95% CI, 0.94–1.00). The optimal cut-off point of the ATFLT was 3.1 mm, with 86.8% sensitivity, 86.0% specificity, and AUC of 0.95 (95% CI, 0.92–0.99).ConclusionATFLA is a new morphological parameter for evaluating chronic ankle sprain, and may even be more sensitive than ATFLT.  相似文献   
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目的 为了提高水中总放射性检测的精密度和正确度,对检测项目系统开展方法验证和质量控制,提升实验室放射卫生和环境监测水平。方法 采用总α分析的厚源法和总β分析的薄样法,对实际样品开展多次分析,计算检测方法的精密度;通过加标回收率实验和2019年全国放射卫生比对样品测试,进行方法的正确度分析。结果 精密度实验中,相同样品多次分析的总α、总β结果相对标准偏差分别为23%和13%;3次加标回收率实验结果分别为103.1%、103.5%和105.8%;2019年全国水中总α、总β比对样品测量结果,与参考值的相对误差分别为0.92%和9.4%,体现了较高的正确度。结论 方法验证和质量控制工作中的相对标准偏差、回收率、相对误差均在标准限制范围之内。这项工作系统介绍了水中总α、总β放射性检测可能引入误差的主要环节,进一步提高了放射卫生和环境放射性监测的水平。  相似文献   
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A number of studies have shown that mental challenge under controlled experimental conditions is associated with elevations in inflammatory markers such as interleukin-6 (IL-6) and C-reactive protein (CRP). However, relatively little work has been done on the effects of ‘naturalistic’ stressors on acute changes in inflammatory markers. The present study examined whether perceived arousal, valence and dominance in musicians are associated with pro-inflammatory and oxidative responses to a concert situation. Blood and salivary samples obtained from 48 members of a symphony orchestra on the day of rehearsal (i.e. control situation) and on the following day of premiere concert (i.e. test situation) were used to determine changes in salivary cortisol, pro-inflammatory markers (plasma myeloperoxidase, serum CRP, plasma IL-6), oxidative stress markers (paraoxonase1 activity and malondialdehyde), and homocysteine, a risk factor for vascular disease. Results of regression analyses showed a significant trend to increased myeloperoxidase (MPO) response in individuals with low valence score. Both affective states, valence and arousal, were identified as significant predictors of cortisol response during concert. In addition, control levels of plasma malondialdehyde were positively correlated with differences in IL-6 levels between premiere and rehearsal (r = .38, p = .012), pointing to higher oxidative stress in individuals with pronounced IL-6 response. Our results indicate that stress of public performance leads to increased concentrations of plasma MPO (20%), IL-6 (27%) and salivary cortisol (44%) in musicians. The decreasing effect of pleasantness on the MPO response was highly pronounced in non-smokers (r = −.60, p < .001), suggesting a significant role of emotional valence in stress-induced secretion of MPO. Additional studies are needed to assess the generalizability of these findings to other ’naturalistic’ stress situations.  相似文献   
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