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The objective of this paper was to assess the link between premature mortality and a combination of neighbourhood contextual (environmental and health) and compositional (socioeconomic and demographic) characteristics. We statistically and spatially examined six environmental variables (ultrafine particles, carcinogenic and non-carcinogenic pollutants, pollution released to air, tree cover, and walkability index), six health service indicators (number health providers, breast, colorectal and cervical cancer screening uptake rates, student nutrition program uptake rates, and healthy food index), and eight socioeconomic indicators (total income, Gini coefficient, two age categories – below and above 40 years, proportion of females to males, visible minorities, Indigenous peoples, education, less than grade 9) among 140 neighbourhoods of the City of Toronto in Ontario (Canada). We applied principal component analysis to identify patterns and to reduce the number of explanatory variables into combined component axes that represent unique variation in these confounded and overlapping factors. We then applied regression analysis to model the relationship between the indices of enviro-health and socioeconomics and their potential relationship with premature mortality. Residual spatial analysis was used to investigate any remaining spatial structure (such as neighbourhoods with higher residual premature mortality rates). Neighbourhood Equity Index was correlated with our enviro-health and socioeconomic indices. Premature mortality within neighbourhoods was predicted by poor cancer screenings, pollution, lack of tree canopy, increased uptake of student nutrition programs and high walkability index. A negative association between premature mortality and pollution was associated low walkability index and presence of visible minorities within neighbourhoods. There was some unexplained residual spatial variation in our model of premature mortality - especially along the shores of Lake Ontario and in neighbourhoods with major highways or road corridors: premature mortality in Toronto neighbourhoods was higher than expected along highway-corridor neighbourhoods and shorelines. Our analysis revealed a significant relationship between neighbourhood contextual features – both environmental and health – and premature mortality, suggesting that these contextual components of neighbourhoods can predict rates of urban premature mortality in Toronto.  相似文献   
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本文回顾了Er:YAG激光活化根管冲洗技术的最新研究进展,包括光子诱导光声流(photon initiated photoacoustic streaming,PIPS)技术和冲击波增强发射光声流(shock wave enhanced emission photoacoustic streaming,SWEEPS)技术,探讨Er:YAG激光预处理桩道的原理、优点以及对纤维桩粘接强度的影响,以期为临床选择适宜的桩道处理方法提供新思路。  相似文献   
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《Surgery (Oxford)》2021,39(9):591-597
Infections of the ear, nose and throat are common. The majority of these infections are managed by the primary care physicians and they settle with conservative and medical management. However, a small group can progress to become troublesome and develop complications to the extent that they may require surgical intervention. Some of the infections can lead to life-threatening complications, therefore awareness and correct diagnosis along with appropriate management is paramount. Foreign bodies in the ear, nose and throat are commonly encountered. The location and type of foreign body can have an implication on the urgency of action and the possible complications. In this article the common ENT infections and foreign bodies and their management are discussed.  相似文献   
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目的探讨下腰痛患者腰椎终板Modic退变、椎间盘退变及CT引导下腰椎间盘造影疼痛激发试验的相关性.方法对45例下腰痛患者常规行腰椎X线和MR检查,分别按Modic终板退变标准(0~3级)与Pearce椎间盘退变标准(Ⅰ~Ⅴ级)对终板和椎间盘进行评估.在CT引导下对45例患者中的40例(120个椎间盘)进行造影和疼痛激发试验,并按Dallas椎间盘造影分级系统(DDD)测评椎间盘退变程度.采用SPSS 11.5统计学软件分析腰椎终板Modic退变、椎间盘退变与腰椎间盘造影疼痛激发试验之间的相关性.结果40例下腰痛患者的腰椎终板Modic分级与椎间盘退变Pearce分级存在较强的相关性(Pearson x^2=43.326,P=0.000),与椎间盘造影疼痛激发试验有显著相关性(Pearson x^2=27.858,P=0.000);椎间盘退变Pearce分级与CT椎间盘造影椎间盘退变Dallas分级也呈较强的相关性.结论腰椎终板Modic退变分级与椎间盘退变Pearce分级密切相关,而与椎间盘疼痛激发试验有显著相关性,提示终板Modic退变可能是下腰痛的原因之一.  相似文献   
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In a retrospective study using univariate analysis, we identified tumor type (nonendometrioid vs endometrioid), depth of myoinvasion (MI), mode of MI (infiltrative vs cohesive), and direct anatomic invasion of the cervical wall from the isthmus as significant positive risk factors for intramyometrial lymphvascular space involvement (LVSI). On multivariate analysis, tumor grade, depth of MI, and mode of MI retained their significance. We created a grid for the relative risks of LVSI with respect to these variables individually or in combination. We suggest that our indirect estimate of the risk of LVSI can help in assessing prognosis and determining the need for adjuvant therapy whenever LVSI is important in clinical decision making, but its pathologic diagnosis is uncertain.  相似文献   
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目的 探讨儿童颈椎间盘钙化症的影像表现及诊断价值,并提高对本病的认识。方法 回顾分析16例儿童颈椎钙化性椎间盘病的影像表现。结果 16例患均行颈椎平片检查,5例行CT扫描并作了三维重建,8例行MRI检查。16例平片均显示了椎间盘钙化灶,均为单发,CT平扫加三维重建显示4例钙化呈卵圆形,1例钙化为不规则形。MRI检查不仅显示了椎间盘内改变还清晰显示了病变相邻椎体边缘信号改变,在T1、T2加权像上呈低信号。结论 平片检查可以显示椎间盘钙化;CT平扫加三维重建能清晰显示了钙化灶的大小、形态;MRI检查在显示受累椎体及周围组织的改变方面明显优于CT和平片。  相似文献   
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目的:观察正压压膜式间隙保持器的临床应用特点和效果.方法:选择60例5.9~10岁的乳牙过早缺失的患儿,随机分为实验组和对照组,实验组用正压压膜式间隙保持器,对照组用带环式丝圈间隙保持器.分别从患者对保持器的接受程度、保持器的制作、椅旁操作时间、固位效果及其保持疗效和因保持器本身问题导致的复诊率进行对比研究,并对测量数据进行统计学处理.结果:两组患者在对保持器的接受程度、保持器的制作、椅旁操作时间、美观、防止对合牙过度伸长方面具有显著的差异,在固位效果及其保持疗效和因保持器本身问题的复诊率上有差异,但是差异没有显著性.结论:正压压膜式间隙保持器是一种美观舒适,制作简单,戴用便捷、固位好,疗效佳,便于观察恒牙萌出程度的间隙保持器,它为口腔医师进行保持缺隙治疗时提供了一种新的选择.  相似文献   
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目的 检测腰椎间盘髓核组织中基质金属蛋白酶-9(MMP-9)的表达,进一步阐明椎间盘退变的机制。方法 利用RT-PCR和Western-Blot技术,对20例正常腰椎间盘髓核、45例退变腰椎间盘髓核的MMP-9进行了检测。结果 正常腰椎间盘组髓核内有一定量的MMP-9表达,退变腰椎间盘组髓核MMP-9mRNA、蛋白质表达水平升高,分别是正常组的1.86和1.65倍,存在差异(P〈0.05)。结论 MMP-9与腰椎间盘髓核退变关系密切。  相似文献   
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