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1.
The aim of this study was to investigate a novel apical U-shape splitting technique for horizontal bone augmentation in undercut areas and to compare its efficacy with that of guided bone regeneration (GBR). This was a prospective non-randomized controlled clinical trial. A total of 36 patients, who presented with a labial undercut that was not able to house a normally inclined implant, underwent the new technique or GBR. Radiographic and clinical data were obtained preoperatively, immediately after surgery, and 12 months after surgery. Pairwise comparisons of changes in ridge width gain, marginal bone loss, and pink aesthetic score were performed; correlations with pristine ridge morphology were investigated. The results showed similar marginal bone loss in the two groups. The overall ridge width gains in the new technique group (2.56 ± 1.92 mm) and GBR group (0.73 ± 1.21 mm) differed significantly (P < 0.05). The pink aesthetic score was higher for the new technique group (11.75 ± 1.22) than for the GBR group (9.25 ± 1.86) (P < 0.01). The morphology of the concavity had different impacts on regeneration in the two groups. The apical U-shape splitting technique, as a safe and effective alternative to GBR, provided a significant increase in bone volume gain where labial fenestration was inevitable during implant placement.  相似文献   
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Foot‐and‐mouth disease (FMD) is highly contagious and easily transmitted among species of cloven‐hoofed animals. To investigate the transmission of FMD virus (FMDV) among different animal species, experimental infections using the O/JPN/2010 strain were performed in cows, goats and pigs. One cow or two goats/pigs were housed with a different species of inoculated animals, and clinical observations, virus shedding and antibody responses were analysed daily. Whilst all cows and goats were infected horizontally by contact with inoculated pigs, transmission from cows to goats/pigs and from goats to cows/pigs was not observed in all in‐contact animals. In particular, no pigs were infected horizontally by contact with inoculated goats. Comparison with our previous study on experimental infections among animals of the same species indicates that horizontal transmission occurred more easily between animals of the same species than between those of the different species. These findings will be useful for establishing and performing species‐specific countermeasures in farms and regions where multiple species of animals coexist in potential future outbreaks.  相似文献   
4.
Purpose: Small pulmonary lesions that include ground-glass attenuation have been increasingly discovered because of progressive imaging diagnostic technologies. Despite the detection of such small lesions, sometimes it is quite difficult to localize them because of their size or considerable depth from the visceral pleura. In the present study, we examined the usefulness of computed tomography-guided lipiodol marking for thoracoscopic resection of impalpable pulmonary nodules.Methods: Fifty-six patients with an undiagnosed peripheral lesion(s) of the lung who had undergone preoperative computed tomography-guided lipiodol marking followed by video-assisted thoracoscopic surgery were studied.Results: All of the nodules were successfully marked by computed tomography-guided lipiodol marking, and all except for one case were localized by means of intraoperative fluoroscopy as clear spots. With regard to complications, pneumothorax occurred in 21 patients (37.5%), and only one patient required transient drainage. Although hemorrhaging in the lung parenchyma and hemosputum occurred in nine patients (16.1%) and one patient (1.8%), respectively, no patients were in serious condition. No intra- or postoperative mortality or morbidity was observed.Conclusion: Preoperative computed tomography-guided lipiodol marking of small or impalpable pulmonary nodules is a safe and useful procedure for thoracoscopic resection of the lung.  相似文献   
5.
The most diverse marine ecosystems, coral reefs, depend upon a functional symbiosis between a cnidarian animal host (the coral) and intracellular photosynthetic dinoflagellate algae. The molecular and cellular mechanisms underlying this endosymbiosis are not well understood, in part because of the difficulties of experimental work with corals. The small sea anemone Aiptasia provides a tractable laboratory model for investigating these mechanisms. Here we report on the assembly and analysis of the Aiptasia genome, which will provide a foundation for future studies and has revealed several features that may be key to understanding the evolution and function of the endosymbiosis. These features include genomic rearrangements and taxonomically restricted genes that may be functionally related to the symbiosis, aspects of host dependence on alga-derived nutrients, a novel and expanded cnidarian-specific family of putative pattern-recognition receptors that might be involved in the animal–algal interactions, and extensive lineage-specific horizontal gene transfer. Extensive integration of genes of prokaryotic origin, including genes for antimicrobial peptides, presumably reflects an intimate association of the animal–algal pair also with its prokaryotic microbiome.Coral reefs form marine-biodiversity hotspots that are of enormous ecological, economic, and aesthetic importance. Coral growth and reef deposition are based energetically on the endosymbiosis between the cnidarian animal hosts and photosynthetic dinoflagellate algae of the genus Symbiodinium, which live in vesicles within the gastrodermal (gut) cells of the animal and typically supply ≥90% of its total energy, while the host provides the algae with a sheltered environment and the inorganic nutrients needed for photosynthesis and growth (1). This tight metabolic coupling allows the holobiont (i.e., the animal host and its microbial symbionts) to thrive in nutrient-poor waters. Although the ecology of coral reefs has been studied intensively, the molecular and cellular mechanisms underlying the critical endosymbiosis remain poorly understood (2). As coral reefs face an ongoing and increasing threat from anthropogenic environmental change (3), new insights into these mechanisms are of critical importance to understanding the resilience and adaptability of coral reefs and thus to the planning of conservation strategies (4).Aiptasia is a globally distributed sea anemone that harbors endosymbiotic Symbiodinium like its Class Anthozoa relatives the stony corals (Fig. 1 and SI Appendix, Fig. S1A) (4, 5). Aiptasia has a range of polyp sizes convenient for experimentation and is easily grown in laboratory culture, where it reproduces both asexually (so that large clonal populations can be obtained) and sexually (allowing experiments on larvae and potentially genetic studies), and it can be maintained indefinitely in an aposymbiotic (dinoflagellate-free) state and reinfected by a variety of Symbiodinium strains (6, 7). These characteristics make Aiptasia a highly attractive model system for studies of the molecular and cellular basis of the cnidarian–dinoflagellate endosymbiosis (2, 4). To provide a solid platform for research on Aiptasia, we have sequenced and analyzed its genome. The results have already provided important insights into several aspects of the evolution and function of the symbiotic system.Open in a separate windowFig. 1.Phylogenetic position and different symbiotic states of Aiptasia. (A) Partial phylogenetic tree (see SI Appendix, SI Materials and Methods and Fig. S1A for details) shows Aiptasia grouped with other anthozoans among the cnidarians. Numbers on nodes denote bootstrap values. (B–D) An aposymbiotic Aiptasia polyp (B) and symbiotic polyps viewed under white light (C) or by fluorescence microscopy to visualize the red chlorophyll autofluorescence of the endosymbiotic Symbiodinium algae (D).  相似文献   
6.
目的 了解我国手术室护士遭遇护际间横向暴力的现状及应对方式,为制订针对性的管理举措提供参考。 方法 采用自制护际间横向暴力事件问卷、护际间横向暴力事件相关问卷,对我国31个省市、自治区医疗机构的3 324名手术室护士进行调查。 结果 80.02%手术室护士曾遭遇过护际间横向暴力,84.75%此前从未听说过横向暴力或了解很少;遭受暴力后63.87%手术室护士产生过跳槽或离职的想法;61.64%认为应积极营造和谐的手术室团队氛围、50.42%认为应提高手术室护士人际沟通能力。 结论 手术室护士普遍存在护际间横向暴力,给受害一方护士带来生理、心理、个人职业发展及人际关系等诸多方面的影响,管理者应引起重视,有效避免手术室护士护际间横向暴力的发生。  相似文献   
7.
Antibiotic resistance, especially in gram-negative bacteria, is spreading globally and rapidly. Development of new antibiotics lags behind; therefore, novel approaches to the problem of antibiotic resistance are sorely needed and this commentary highlights one relatively unexplored target for drug development: conjugation. Conjugation is a common mechanism of horizontal gene transfer in bacteria that is instrumental in the spread of antibiotic resistance among bacteria. Most resistance genes are found on mobile genetic elements and primarily spread by conjugation. Furthermore, conjugative elements can act as a reservoir to maintain antibiotic resistance in the bacterial population even in the absence of antibiotic selection. Thus, conjugation can spread antibiotic resistance quickly between bacteria of the microbiome and pathogens when selective pressure (antibiotics) is introduced. Potential drug targets include the plasmid-encoded conjugation system and the host-encoded proteins important for conjugation. Ideally, a conjugation inhibitor will be used alongside antibiotics to prevent the spread of resistance to or within pathogens while not acting as a growth inhibitor itself. Inhibiting conjugation will be an important addition to our arsenal of strategies to combat the antibiotic resistance crisis, allowing us to extend the usefulness of antibiotics.  相似文献   
8.
磨牙阻生多见于上下颌第三磨牙,第一磨牙阻生相对罕见。本文报道下颌第一磨牙水平阻生1例,并结合相关文献对其进行讨论。  相似文献   
9.
Tsunami generation from earthquake-induced seafloor deformations has long been recognized as a major hazard to coastal areas. Strike-slip faulting has generally been considered insufficient for triggering large tsunamis, except through the generation of submarine landslides. Herein, we demonstrate that ground motions due to strike-slip earthquakes can contribute to the generation of large tsunamis (>1 m), under rather generic conditions. To this end, we developed a computational framework that integrates models for earthquake rupture dynamics with models of tsunami generation and propagation. The three-dimensional time-dependent vertical and horizontal ground motions from spontaneous dynamic rupture models are used to drive boundary motions in the tsunami model. Our results suggest that supershear ruptures propagating along strike-slip faults, traversing narrow and shallow bays, are prime candidates for tsunami generation. We show that dynamic focusing and the large horizontal displacements, characteristic of strike-slip earthquakes on long faults, are critical drivers for the tsunami hazard. These findings point to intrinsic mechanisms for sizable tsunami generation by strike-slip faulting, which do not require complex seismic sources, landslides, or complicated bathymetry. Furthermore, our model identifies three distinct phases in the tsunamic motion, an instantaneous dynamic phase, a lagging coseismic phase, and a postseismic phase, each of which may affect coastal areas differently. We conclude that near-source tsunami hazards and risk from strike-slip faulting need to be re-evaluated.

Tsunamis are classically defined as long, free-surface water waves generated by impulsive geological events (1). Tsunamis may be triggered by earthquakes, volcanoes, landslides or slumps, submarine gas releases, and meteorite impacts. Over the past century, tsunamis alone have been responsible for the loss of hundreds of thousands of lives and trillions of dollars in damage to the environment and built infrastructure (2, 3). This makes tsunamis among the most destructive natural hazards. Quantitative and predictive modeling of tsunamis is crucial for reducing the impact of these events and for enabling better preparedness plans.Generally, the tsunami impact is associated with the size of the vertical seafloor motion. Massive tsunamis are generally attributed to great earthquakes along subduction-zone plate boundaries, such as the 2004 M9.2 Sumatran and the 2011 M9.0 Tohoku-Oki events. Strike-slip faults, which generally generate small seafloor vertical displacements, are generally considered unfavorable for tsunami generation (4). Field observations, however, suggest that in many cases (59), strike-slip motion can indeed generate tsunami waves, supposedly by triggering landslides (10). Even though a small fraction of all tsunamis studied this far are believed to be triggered by strike-slip motion (11), their possible devastating humanitarian impact warrants further investigation into this particular mechanism for tsunami genesis.The September 2018 Mw 7.5 Sulawesi earthquake occurred on the Palu-Koro (P-K) strike-slip fault system and caused an unexpected localized tsunami, atypical in its impact for this type of fault motion (12). Bao et al. (13) and Socquet et al. (14) were among the first to recognize the supershear nature of this earthquake (13, 14). Several authors (13, 1517) have postulated that submarine landslides, triggered by the earthquake’s strong ground motion, were the primary source for the devastating tsunami. Ulrich et al. (18) argued that the earthquake displacements were critical to the tsunami generation. Using a three-dimensional (3D) dynamic rupture model that emulated the earthquake propagation on the geometrically complex P-K fault system and coupling it with the two-dimensional (2D) shallow-water wave equations, they demonstrated that the fault slip, which included a nonnegligible rake and dip slip components, may only trigger tsunami waves of the order of a meter. Their conclusions, however, are confounded by the specifics of the complex Palu Bay bathymetry and the complex geometry of the P-K fault system.Amlani et al. (19) utilized near-fault GPS data to first conclusively demonstrate that the P-K rupture was indeed supershear. They then recovered a crucial term in the shallow-water wave equation by including the time derivative of the seafloor vertical displacements and, thus, ensured correct mass conservation (20). This forcing was implemented in the context of a one-dimensional (1D) nonlinear shallow-water wave model and a simple bathymetry, driven dynamically by the vertical components of the motion computed from a 3D dynamic rupture simulation of a supershear earthquake along a strike-slip fault. They showed that explicitly accounting for the dynamic source effects uncovers high-frequency details in the early phases of the tsunami motion. They claimed these details may get missed if only the static seafloor displacements are used. However, they did not consider the effect of horizontal displacements in the ground motion on deforming the bathymetry. Furthermore, their 1D model could not account for the dramatic focusing effect introduced by water waves converging at, and subsequently reflected and refracted from, the apex of any narrow bay. These limitations possibly led to a noticeable underprediction of the calculated amplitude of the waves.The question, therefore, remains whether generic strike-slip faults, in the absence of secondary sources, such as coseismic underwater landslides, can generate large tsunamis. This question has important ramifications, as several metropolitan areas worldwide are located near bays (6, 7, 2123) that are traversed by strike-slip faults similar to the P-K system. Furthermore, while early warning for far-field tsunamis (1, 24, 25) based on hydrodynamic inversions is now fairly routine, at least in the North Pacific, little or no early warning is possible for near-field tsunamis, in which the tsunami originates just a few kilometers away from the coastline. Most field scientists agree that, thus far, for coastal residents, earthquake shaking is the warning for an impending tsunami from a nearshore source (26, 27).To shed light on the basic mechanisms through which strike-slip faults may cause damaging tsunamis, we have developed a computational framework that integrates mechanistic models for earthquake rupture dynamics with hydrodynamic models for tsunami generation and propagation. Possibly with a few exceptions, the initial condition in tsunami models is computed by using the static algorithms of Mansinha and Smylie (28), subsequently parameterized by Okada (29), which translate finite fault slip models into static seafloor displacements. In recent years, there has been an increased interest in developing models that account for dynamic generation (18, 3033). Here, we use our dynamic generation model and focus on a planar strike-slip fault traversing a shallow bay with a simple geometry. Tsunami evolution over a more complex bathymetry may hide the effects of the dynamic rupture. Our approach is thus designed to unravel the underlying physics governing tsunami generation due to the intrinsic nature of strike-slip faulting. In other words, we seek to understand the basic phenomenology first, before applying our model to complex geophysical geometries.The 2018 Palu earthquake and tsunami highlighted the complex dynamics of tsunamis generated by intersonic earthquakes. In supershear, or intersonic, earthquakes (3440), the rupture tip propagates faster than the shear wave speed (4143). This leads to the emergence of large localized deformation bands along the shear shock wave fronts, also known as Mach cones (34, 35, 38, 39, 44). Dunham and Bhat (38) proved the presence of a second Mach front associated with Rayleigh waves that carry significant vertical motion, moderately attenuated, to large distances. When such earthquakes occur within a narrow bay, the associated large horizontal displacements, as well as the moderately attenuated vertical displacements (34, 39, 45), along the shear and Rayleigh shock wave fronts may cause significant motion in the bay boundaries, which, just as with a paddle wavemaker, could lead to the displacement of large volumes of water. Furthermore, in these scenarios, the triggered tsunami may exhibit multiple characteristic time scales, ranging from a few seconds to several minutes.In the following sections, we investigate the synergistic interactions between rupture speed, seafloor ground motions, and bay geometry. We also examine several distinct features of the tsunami, including the emergence of an instantaneous dynamic phase and a slower coseismic phase, both of which lead to a gravity-driven postseismic phase.  相似文献   
10.
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