颈椎终板弧形高度与椎间隙后缘骨赘的相关性研究

目的：通过对颈椎病患者上下终板弧形高度、椎间隙高度与椎间隙后骨赘的影像学测量，研究其相关性及其临床应用价值。方法：收集2017年9月至2018年9月颈椎病手术108例患者的临床资料，男48例，年龄30~72岁，平均52岁，女60例，年龄37~79岁，平均54岁。其中C_2，3 6例，C_3，4 15例，C_4，5 32例，C_5，6 42例，C_6，7 13例。术前及术后摄颈椎X线片，利用PACS（Picture Archiving and Communication Systems）调阅影像，测量椎间隙的下上终板弧形高度（L₁，L₂），椎间隙高度（L₃）及后方骨赘的宽度（L₄）。利用Spearman分析它们之间的相关性。结果：L₁与L₄对比（r=-0.34，P<0.05），L₃与L₄对比（r=-0.36，P<0.05），存在负相关。L₁与L₃对比（r=0.38，P<0.05），L₂与L₃对比（r=0.48，P<0.05），存在正相关。L₁与L₂对比（P>0.05），L₂与L₄对比（P>0.05），差异无统计学意义。结论：下终板弧形高度与椎间隙后缘骨赘宽度呈负相关，通过其测量可明确颈椎退变程度，对颈椎病的早期防治有指导意义。     

The influence of environmental and health indicators on premature mortality: An empirical analysis of the City of Toronto's 140 neighborhoods

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.     

Er:YAG激光桩道预处理的研究进展

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。     

Infections and foreign bodies in ENT

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.     

Revisiting the Hydrogen Storage Behavior of the Na-O-H System

Solid-state reactions between sodium hydride and sodium hydroxide are unusual among hydride-hydroxide systems since hydrogen can be stored reversibly. In order to understand the relationship between hydrogen uptake/release properties and phase/structure evolution, the dehydrogenation and hydrogenation behavior of the Na-O-H system has been investigated in detail both ex- and in-situ. Simultaneous thermogravimetric-differential thermal analysis coupled to mass spectrometry (TG-DTA-MS) experiments of NaH-NaOH composites reveal two principal features: Firstly, an H₂ desorption event occurring between 240 and 380 °C and secondly an additional endothermic process at around 170 °C with no associated weight change. In-situ high-resolution synchrotron powder X-ray diffraction showed that NaOH appears to form a solid solution with NaH yielding a new cubic complex hydride phase below 200 °C. The Na-H-OH phase persists up to the maximum temperature of the in-situ diffraction experiment shortly before dehydrogenation occurs. The present work suggests that not only is the inter-phase synergic interaction of protic hydrogen (in NaOH) and hydridic hydrogen (in NaH) important in the dehydrogenation mechanism, but that also an intra-phase H^δ+… H^δ– interaction may be a crucial step in the desorption process.     

Heteroepitaxy of Cerium Oxide Thin Films on Cu(111)

An important part of fundamental research in catalysis is based on theoretical and modeling foundations which are closely connected with studies of single-crystalline catalyst surfaces. These so-called model catalysts are often prepared in the form of epitaxial thin films, and characterized using advanced material characterization techniques. This concept provides the fundamental understanding and the knowledge base needed to tailor the design of new heterogeneous catalysts with improved catalytic properties. The present contribution is devoted to development of a model catalyst system of CeO₂ (ceria) on the Cu(111) substrate. We propose ways to experimentally characterize and control important parameters of the model catalyst—the coverage of the ceria layer, the influence of the Cu substrate, and the density of surface defects on ceria, particularly the density of step edges and the density and the ordering of the oxygen vacancies. The large spectrum of controlled parameters makes ceria on Cu(111) an interesting alternative to a more common model system ceria on Ru(0001) that has served numerous catalysis studies, mainly as a support for metal clusters.     

Effect of catalase supplementation in storage media for avulsed teeth

Abstract – The type of liquid medium used to store avulsed teeth prior to replantation has been shown to affect the long‐term prognosis. One possibility is that some storage media contain hydrogen peroxide (H₂O₂) that may be toxic to periodontal ligament cells. Therefore, the aim of this study was to determine if the addition of catalase to storage media improved the prognosis of replanted dog teeth. Forty‐eight mongrel premolar roots were endodontically treated, extracted, randomly divided and placed into one of four storage media: Hank's balanced salt solution (HBSS), containing no antioxidant); Viaspan, containing the antioxidant, glutathione, or the same two media supplemented with catalase(100 U ml^?1) for 1, 5, or 26 h prior to replantation. After 2 months, the dogs were euthanized and the roots histologically examined to evaluate the attachment tissues. Regardless of the storage medium used, overall healing was excellent and only 4% of the roots displayed inflammatory or replacement resorption. When roots from the different storage media were compared, those stored in HBSS were found to display the highest incidence of surface resorption (55.7%). Supplementation of HBSS with catalase resulted in a lower level of surface resorption (48.6%) that was statistically significant (P < 0.05). Roots stored in Viaspan – or + catalase displayed even lower levels of surface resorption (41.3 and 38.2%, respectively). The improvement observed with catalase‐supplemented HBSS was confined to the 45‐min incubation period; only Viaspan – or + catalase reduced surface resorption at the 5‐ and 26‐h incubations. Collectively, these data demonstrate that roots stored in media containing antioxidant activity undergo less surface resorption. These results suggest that low levels of H₂O₂ in storage media for avulsed teeth may adversely affect periodontal ligament cells.     

Statistical analysis of pathologic risk factors for intramyometrial lymphvascular space involvement in myoinvasive endometrial carcinoma

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.