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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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目的 应用可视化方法分析代谢组学在中医药领域的现状及趋势。方法 检索中国知网数据库(CNKI)和Web of Science 核心合集数据库2021年3月15日之前收录的中医药领域代谢组学研究的相关文献,应用CiteSpace软件对纳入的文献进行关键词、作者、研究机构等内容进行可视化分析。结果 共纳入中文文献247篇,英文文献350篇。文献数量在波动中迅速上升。中、英文文献作者合作网络显示,张爱华是中医药领域代谢组学研究发文量最多的作者,并形成了核心研究团队。发文机构显示,中国医学科学院是该领域的重要研究机构,机构间合作紧密。中、英文文献关键词分析显示,研究内容主要集中在核磁共振、代谢标记物、冠心病、质谱技术、代谢通路等相关领域。结论 中医药领域代谢组学研究的热点主要为中医药治疗代谢性疾病的机制研究。研究趋势为卵泡代谢组学研究及中药有效成分的研究。  相似文献   
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目的:探讨脑出血对酵母沉默信息调节因子2(Sirt2)和炎症的影响。方法:将胶原酶Ⅳ注入SD大鼠右侧 纹状体中建立脑出血模型,通过免疫印迹和ELISA 等方法测定大鼠脑出血后48 h 的Sirt2 的表达及炎症变化。利 用Hemin 诱导PC12 细胞损伤模拟体外脑出血模型,并检测Sirt2 及炎症变化;采用短发夹RNA(shRNA)-Sirt2 沉 默Sirt2 在PC12 细胞中的表达及对炎症的影响。结果:手术后48 h 脑出血行为学评分最低。脑出血组Sirt2 的表达 显著高于假手术组。脑出血组IL-6、IL-1β 表达显著升高。结论:脑出血可以促进Sirt2 的表达和炎症反应,降低 Sirt2 的表达可减缓炎症反应。 关键词 脑出血;沉默信息调节  相似文献   
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目的:通过中英文文献了解结直肠癌患者生命质量研究现状及发展趋势。方法:运用CiteSpace对中国知网(CNKI)、万方数据知识服务平台、中国生物医学文献数据库、Web of Science核心数据集、PubMed、Cochrane Library中收录的关于结直肠癌患者生命质量研究的中英文文献进行可视化分析。结果:检索得到中文文献1 285篇,英文文献871篇,中英文文献发文量均呈上升趋势,相关研究关注的重点主要是结直肠癌患者造口、抑郁、免疫、肠道功能、化疗及化疗药物,但机构之间、学者之间合作程度及研究类型等方面存在一定差异。结论:中文文献相关研究起步晚、发展快,但在研究质量与研究深度等方面与英文文献相比还有一定差距;国内学者之间、机构之间应加强合作,关心患者肠道功能、心理状况,提高患者体力活动水平,开展更多高质量研究。  相似文献   
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【目的】 研究我国中文SCI科技期刊的现状,以期为其影响力提升和未来发展提供思考。【方法】 利用网站调研(期刊官网和Web of Science数据库等)、微信公众号运营情况查询及统计分析等方法对中文SCI科技期刊进行较全面的数据采集与分析。【结果】 18种中文SCI科技期刊有深厚的历史积淀和良好的发展基础,但整体上仍存在一些问题,如国内影响力不如优秀的纯中文期刊(国内影响力排名不够靠前),国际影响力不高(JCR分区仅为Q3或Q4区),国际化发展程度不够(国际编委占比为0的期刊高达11种,缺乏国际新媒体宣传),不够重视网络首发(仅9种期刊有网络首发)等。【结论】 在目前国内良好政策环境下,我国中文SCI科技期刊需要坚守初心,可根据各自期刊定位制定个性化发展策略,从而发展成为旗舰期刊甚至是世界一流期刊。  相似文献   
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【目的】 在“中国科技期刊卓越行动计划”实施三周年之际,有必要对我国科技期刊2035年迈入“世界第一方阵”目标的具体任务进行重新审视和预判,以进一步明确发展方向,动态调整推进思路。【方法】 采用国内外科技期刊、科技论文、科技期刊评价成果的系统性发展数据对科技期刊“世界第一方阵” 国家(或地区)在高水平科技期刊数量与质量层面的入围标准进行界定,在深入总结现有基础和优势的同时,对我国科技期刊综合实力与“世界第一方阵”国家(或地区)的现实差距进行逐一梳理和剖析,并对实现目标的可行性和推进思路进行研判和设计。【结果】 必须继续加强高水平英文科技期刊创办和培育力度、持续加大优秀中文科技期刊的建设强度、快速推进国内外科技期刊论文等质同效评价制度的建设与引导,并积极探索建立科学家和科研机构办好一流科技期刊的责任制度和贡献激励机制、创新发展编辑人才队伍培养与激励管理思路、深入实践灵活多样的期刊出版市场资本运作模式、稳步推进期刊出版市场机制和管理制度改革,为我国科技期刊事业的高质量发展提速增效。【结论】 虽然当前阶段目标任务艰巨,但迈入“世界第一方阵”未来可期。  相似文献   
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Most surgical and anaesthetic mortality and morbidity occurs postoperatively, disproportionately affecting low- and middle-income countries. Various short courses have been developed to improve patient outcomes in low- and middle-income countries, but none specifically to address postoperative care and complications. We aimed to identify key features of a proposed short-course addressing this topic using a Delphi process with low- and middle-income country anaesthesia providers trained as short-course facilitators. An initial questionnaire was co-developed from literature review and exploratory workshops to include 108 potential course features. Features included content; teaching method; appropriate participants; and appropriate faculty. Over three Delphi rounds (panellists numbered 86, 64 and 35 in successive cycles), panellists indicated which features they considered most important. Responses were analysed by geographical regions: Africa, the Americas, south-east Asia and Western Pacific. Ultimately, panellists identified 60, 40 and 54 core features for the proposed course in each region, respectively. There were high levels of consensus within regions on what constituted core course content, but not between regions. All panellists preferred the small group workshop teaching method irrespective of region. All regions considered anaesthetists to be key facilitators, while all agreed that both anaesthetists and operating theatre nurses were key participants. The African and Americas regional panels recommended more multidisciplinary healthcare professionals for participant roles. Faculty from high-income countries were not considered high priority. Our study highlights variability between geographical regions as to which course features were perceived as most locally relevant, supporting regional adaptation of short-course design rather than a one-size-fits-all model.  相似文献   
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ObjectivesTrauma appears within the discourse of mentally injured people, materializing what we have recently defined as “post traumatic psycholinguistic syndrome” (SPLIT). Translating unspeakability, revival, and dissociation, this clinical entity associates three significant disturbances : traumatic anomia (missing words, reduction of the elocutionary flow, deictic gestures, etc.); linguistic repetitions (of words and phrases, verbal intrusions, echophrasias, etc.); and phrasal and discursive disorganization (incomplete sentences, tense discordance, dysfluence, lack of logical connectors, etc.). What are the causes of these semiological and psycholinguistic expressions? What are their psychological and/or neuropsychological processes? It is time to come up with a new concept intended to go beyond the previous models in order to better identify people suffering from post-traumatic mental disorders, to better organize and evaluate psychotherapeutic care, and also to help practitioners collaborate more effectively on these first two goals. But how to evoke, affirm, or speak out about the consequences of unspeakability? Nothing is more apparently contradictory than wanting to define the language void. How to account for the fractures of psychic trauma in discourse? Nothing is more uncertain than to try to organize the upheavals, the disorders caused by dissociation in language. Finally, how to specify the reiteration of the trauma using words and sentences without this modeling being dissociative or repetitive? Today, thanks to a psycholinguistic reading, essential dimensions of post-traumatic suffering, hitherto hidden, can be clarified. Why exactly does an event cause trauma in the life of a subject at a given moment in her/his existence? Why is a latency phase structured between the traumatic event and the return of reviviscences under the influence of a re-triggering factor? How to differentiate the notion of dissociation as a normal phenomenon from the so-called traumatic dissociation? How to explain the multiple clinical forms of post-traumatic psychological disorders?MethodsFrom Pierre's clinical history, we chronologically detail the structuring and the consequences of the signified reflection that are constitutive of the psychic trauma: the psycholinguistic tools here help to formulate a new etiopathogenic conception of trauma and its psychological consequences. Then, thanks to Jean's testimony, taking up the retrospective meaning of the clinical analysis from chronic repetition syndrome, we discover the phases of tension regarding signified knowledge, up to the network prior to the traumatic confrontation. Finally, illustrated by Karima's disorder, beyond depersonalization, we explain that the analysis of the disturbances of a singular signified network, and also of an attack on its familial and societal bases, testifies to individual and collective subjectivities.ResultsComing from the real world, and therefore also from the body, the stimuli made up of signals picked up by our senses combine to compose an event that can be objectified by its temporal, spatial, biological, and physico-chemical coordinates. These elements combine into a unit, which is then interpreted by the mind, which attributes meaning to this event, which has become subjective reality. But when the subject is not sufficiently prepared to be confronted with this meaning that appears to be in extreme contradiction with her/his previous cardinal networks of significations, it makes “too much sense:” this irreconcilable hyper-signified (that we call the traumatic signified) results in post-traumatic dissociation. In other words, it is an impossibility of concordance of a signified with certain systems of prior significations that constitutes the pathogenesis of the trauma; and a situation runs a greater risk of being traumatic when it contradicts, or, moreso, endangers some or all of the subject's cardinal meanings. This unbearable signified reflexively blocks the capacities of significations immediately pre- and post-trauma, then dissociates the psychic functions to varying degrees and intensities. The traumatic signified, rejected, becomes unattainable: the stimuli that led to its formation find themselves confined to the state of reviviscences, each replication of which attempts to cross the barrier of inconceivability. Limiting sensory compounds to their raw states without the possibility of representational integration, associative pathways remain blocked. The signifier is referred to a hypo-signifier confined to the infra-linguistic by its confusion with the referent, the “objective and material” components of the traumatic event. Dissociation is therefore only a symptomatic reaction, secondary to the trauma, which it reinforces once again by limiting any possibility of representing the trauma. This dissociation does not involve forgetting the traumatic signified but “protects” the adjacent networks of meanings from it as much as it “keeps” this hypersignified intact, therefore ultimately “protecting” it as well. The traumatic signified persists somewhere, and even ends up being found everywhere: when the networks of meanings turn out to be globally disturbed, the tightest links remain those of the traumatic hypersignified that ultimately governs all the networks of meanings.DiscussionOur insufficient knowledge prevents us from precisely qualifying the architecture of the signified idiosyncratic networks and their evolutionary capacities; we cannot predict, beforehand, the reaction of an individual confronted with a potentially psychotraumatic situation. For most clinical situations, we affirm that the psychological trauma occurs in a psychically healthy subject, that is, not suffering from any psychiatric illness or any obvious psychopathological conflict. Psychotherapy will make it possible to discover the signified, sometimes ancient, origins of a trauma occurring in a singular subject. How was this subjectivity constructed? Beyond individual subjectivity, the intensity of certain confrontations such as serious attacks or macrosocial catastrophes such as genocide, would seem to lead to psychological wounds in any individual, even at the scale of a population. While, throughout existence, each subject produces a system of significations in connection with a unique psychic construction, the latter persists – resulting from, and often remaining overseen by, the community essence of a base of signifying networks, which we call “societal subjectivity.” Here, the psychological trauma can correspond to an individual and “common” injury as a failure of a sharing, or of ancestral beliefs anchored in the collective memory, defining the culture. By the collapse of acquired certainties, the cognitive patterns transmitted by education, language, and everything that establishes one's belonging to a society, trauma shakes the networks of individual and group meanings. Horror has a higher traumatogenic risk, because it defeats the fundamentals of humankind, the foundations of a signified network common to a culture, or even to all cultures, to the human condition. This is the case with murder, rape, torture, wars, genocides. Testifying to an instinct for survival stemming from the biological foundations of every living being, the impossibility of “living death” appears to be anchored in our networks of meanings and is manifested by indescribability, traumatic as such: being deserted by the language collides with the condition of speaking. And yet, it remains possible to say something about it... As a path of progressive desocialization, the occasional loss of the community of language, followed by its lasting traumatic ravages, can be appeased by the reestablishment of a speech link, either within the mind of the subject alone, or promoted by the exchange with others, in a psychotherapeutic setting, for example.ConclusionWhere theoretical discourses have sometimes proved divisive, going beyond the symptoms of indescribability and dissociation, psychodynamic practice today offers to unite. Thanks to psycholinguistic listening, phenomena that have never been explained take on meaning: the singularity of traumatic perception, the chronology of disorders including the latency phase, factors that trigger reviviscences, and the diversity of chronic clinical forms. All these post-traumatic symptoms are consequential to a linguistic wound, a difficulty in accessing meaning, the undermining of two dimensions characterizing and constructing the human being. As much as it integrates extralinguistic determinants, if the traumatic signified is undoubtedly not only speech, language appears the optimal way to identify it as such, while in the same movement appeasing it. The traumatic hypersignified is discovered through clinical analysis and psychotherapy, through deferred action, through the attribution of meaning, through the retrospective reconstruction of an unstable “real,” through a changing narration eternally distancing itself from reviviscences. But what precisely are the mechanisms of effective therapies ? What are the intersubjective links called for in the discussion between patient and practitioner? Could the operations that we call “psychotherapy” be made up of mobilizations of the networks of meanings by speech acts?  相似文献   
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