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1.
Intratumor heterogeneity is a main cause of the dismal prognosis of glioblastoma (GBM). Yet, there remains a lack of a uniform assessment of the degree of heterogeneity. With a multiscale approach, we addressed the hypothesis that intratumor heterogeneity exists on different levels comprising traditional regional analyses, but also innovative methods including computer-assisted analysis of tumor morphology combined with epigenomic data. With this aim, 157 biopsies of 37 patients with therapy-naive IDH-wildtype GBM were analyzed regarding the intratumor variance of protein expression of glial marker GFAP, microglia marker Iba1 and proliferation marker Mib1. Hematoxylin and eosin stained slides were evaluated for tumor vascularization. For the estimation of pixel intensity and nuclear profiling, automated analysis was used. Additionally, DNA methylation profiling was conducted separately for the single biopsies. Scoring systems were established to integrate several parameters into one score for the four examined modalities of heterogeneity (regional, cellular, pixel-level and epigenomic). As a result, we could show that heterogeneity was detected in all four modalities. Furthermore, for the regional, cellular and epigenomic level, we confirmed the results of earlier studies stating that a higher degree of heterogeneity is associated with poorer overall survival. To integrate all modalities into one score, we designed a predictor of longer survival, which showed a highly significant separation regarding the OS. In conclusion, multiscale intratumor heterogeneity exists in glioblastoma and its degree has an impact on overall survival. In future studies, the implementation of a broadly feasible heterogeneity index should be considered.  相似文献   
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儿童处于生长发育特殊阶段,其颌面部解剖结构、牙列情况及心理状态与成年人有明显区别。颌面部骨折患儿常出现面部发育畸形、张口受限、咬合关系紊乱等,严重影响患儿的日常生活。因此,儿童颌面部骨折的诊疗一直是临床上的难题,也是国内外的研究热点。颌面部骨折好发于青少年,损伤原因多为意外跌倒、交通伤及运动伤。近年来,数字化外科技术为儿童颌面部骨折提供精确的诊断及微创的治疗。国内外学者对于儿童颌面部骨折治疗理念逐渐倾向于手术治疗,选择可吸收材料对儿童颌面部骨折进行固定,降低对儿童面部发育的影响。长期随访对于儿童颌面部骨折患儿具有重要意义,有助于监测患儿面部发育情况。此外,临床医生应注意患儿的心理状态。对于创伤较重或发现有心理问题的患儿,应尽早干预治疗。文章就近年儿童颌面部骨折流行病学特点、诊断、治疗原则及伴发的心理问题做一综述。  相似文献   
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??Objective    To observe the effects of lithium chloride pretreatment on cognitive ability of aged rats after oral and maxillofacial surgery. Methods    A total of 48 aged male SD rats??18 ~ 20 months old??weight 550 ~ 700 g?? were bought from the Experimental Animal Center of China Medical University . These rats were randomly divided into three groups??including the normal control group??group C??n=16????surgery and anesthesia group??group O??n=16????and lithium chloride preconditioning group??group L??n=16??.Rats in each group were randomly divided into two parts??one part was given Morris water maze test three days after the surgery and its characteristics of behavior tested. Another part was decapitated 24 h after the surgery and extracted and the hippocampus brain separated at the same time. Test expression content of IL-1β GSK-3β p-GSK-3β??ser9??in the hippocampus by Elisa and Western blotting detection method respectively. Results    Morris water maze test showed that??the first day after surgery??latencies of group L and O were significantly longer than group C??compared with group C in swimming distance?? latency and swim distances of group L were shorter than group O. With the comparison of multiple analysis of variance??differences were statistically significant??P??0.05??. Groups L and O in the second day were slightly shortened compared to the first day??on the third day after surgery it has also improved over the second day. Space exploration experiments in rats showed that??the dwell time of group C was significantly longer in the platform quadrant and the frequency of crossing the platform also increased compared with groups L and O. In addition??group L and group O were higher in IL-β levels than group C??the difference being statistically significant by analysis of variance??P??0.05????but group L was significantly lower compared with group O??the difference being statistically significant??P??0.05??. The content of GSK-3β of three groups were of no significant difference??P > 0.05????but p-GSK-3β??ser9??content was significantly lower in group L and O than in group C. The content of GSK-3β of group L was higher than in group O??the difference being statistically significant??P??0.05??. Conclusion    Pretreatment with lithium chloride in postoperative aged rats can inhibit the expression of inflammatory cytokines and increase GSK-3β phosphorylation in the hippocampus cells??so p-GSK-3β??ser9??upregulates and inhibites  the apoptosis of brain cells??thereby improved cognitive abilities after the cavity and maxillofacial surgery.  相似文献   
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Nanocrystalline platinum with different morphologies is synthesized via electrochemical deposition technique. The nucleation mechanism and its structural effect over the electrodeposited Pt on carbon electrodes have been systematically studied. Powder X-ray diffraction, X-ray photoelectron spectroscopy, and field-emission scanning electron microscopy are employed to study nucleation, oxidation states, and Pt structure growth on a carbon electrode. This study reports significant development of Pt metal nanoparticles with different morphologies such as a sphere, flower, core-flower, and rod-like structure directly fabricated on carbon electrode while tuning the deposition parameters such as current density, time, temperature, pH during the deposition process. The proposed electrochemical route represents a superior fabrication procedure for large-scale electrode fabrication compared to a conventional method for preparing membrane electrode assemblies for fuel cell stacks.  相似文献   
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Oral and maxillofacial surgery (OMS) teaching is set to undergo a paradigm shift towards competency-based training. With increasing focus on resident skill development and patient safety, computerized simulators are likely to play a more mainstream role in OMS training. A systematic review of the available literature was conducted, in accordance with the PRISMA guidelines, to highlight the scope of computerized simulation in OMS teaching. A PubMed search was performed by two independent reviewers, and 35 articles published in English between 2010 and 2021 that reported the use of computerized simulation for teaching maxillofacial procedures were included in the analysis. Eight articles on minor oral surgery, seven on orthognathic surgery, five on maxillofacial trauma, five on cleft lip and palate surgery, three articles each on nerve block techniques, endoscopic procedures, and reconstructive surgery, and one article on fibre-optic intubation reported the use of computerized simulation that can be applied to OMS training. Ten randomized controlled trials were identified in the search. However there was marked heterogeneity among the studies. Simulator training for skill acquisition mentored by an expert OMS educator could offer holistic resident training; however more studies that test common themes of resident training such as knowledge acquisition and skill development are necessary.  相似文献   
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ObjectiveThe objective of this study was to investigate the association between morphological variation and postsurgical pulmonary vein (PV) stenosis (PPVS) in patients with cardiac total anomalous pulmonary venous connection (TAPVC).MethodsThis single-center, retrospective study included 168 pediatric patients who underwent surgical repair of cardiac TAPVC from 2013 to 2019 (connection to the coronary sinus [CS], n = 136; connection directly to the right atrium [RA], n = 32). Three-dimensional computed tomography modeling and geometric analysis were performed to investigate the morphological features; their relevance to the PPVS was examined.ResultsThe connection type had no association with PPVS (CS type: 18% vs right atrial type: 19%; P = .89) but there was a higher incidence of PPVS in patients with a single PV orifice than > 1 orifice (P < .001). Confluence-to-total PV area ratio (hazard ratio, 4.78, 95% CI, 1.86-12.32; P = .001) and length of drainage route (hazard ratio, 1.22; 95% CI, 1.14-1.31; P < .001) had a 4- and 1-fold increase in the risk for PPVS in the CS type after adjustment for age and preoperative pulmonary venous obstruction. In the right atrial type, those with anomalous PV return to the RA roof were more likely to develop PPVS than to the posterior wall of the RA (P < .001).ConclusionsThe number of inter-junction PV orifice correlated with PPVS development in cardiac TAPVC. The confluence-to-total PV ratio, length of drainage route, and anomalous PV return to the RA roof are important predictors for PPVS. Morphological subcategorization in this clinical setting can potentially assist in surgical decision-making.  相似文献   
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Tarentola annularis is a climbing gecko with a wide distribution in Africa north of the equator. In the present paper, we describe the development of the osteocranium of this lizard, from the first appearance of the cranial elements up to the point of hatching. This is based on a combination of histology and cleared and stained specimens. This is the first comprehensive account of gekkotan pre-hatching skull development based on a comprehensive series of embryos, rather than a few selected stages. Given that Gekkota is now widely regarded as representing the sister group to other squamates, this account helps to fill a significant gap in the literature. Moreover, as many authors have considered features of the gekkotan skull and skeleton to be indicative of paedomorphosis, it is important to know whether this hypothesis is supported by delays in the onset of cranial ossification. In fact, we found the sequence of cranial bone ossification to be broadly comparable to that of other squamates studied to date, with no significant lags in development.  相似文献   
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The inferior alveolar nerve and facial nerve are the two most important nerves in the dental and maxillofacial region. The injury to them is one of the major postoperative complications after alveolar surgery and orthognathic surgery. However, recovering the nerve function after injury takes a long time and the recovery effect tends to be unsatisfactory. In recent years, an intensively investigated technique, low level laser which has been applying in assisting the recovery of nerve function, has been gradually proved to be effective in clinically treating postoperative nerve injury. In this article we review in terms of the mechanisms involved in low level laser-assisted functional restoration of nerve injury and its clinical application in the recovery of nerve function in the dental and maxillofacial area as well.  相似文献   
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