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71.
目的:基于原发肿瘤及淋巴结CT特征建立评分模型预测食管鳞癌患者喉返神经旁淋巴结(RLN-LN)转移风险。方法:回顾性收集2014年1月至2019年12月于北京大学肿瘤医院行食管癌根治术并清扫RLN-LN的92例食管鳞癌患者。根据术后淋巴结病理结果分为RLN-LN转移组(n=37)和非转移组(n=55)。评估术前CT图像,记录食管癌患者年龄、性别、分化程度、肿瘤位置、肿瘤大小(肿瘤长度、肿瘤厚度、厚度/长度)、RLN-LN大小(淋巴结短径、长径、短径/多平面重建(MPR)最长径]。采用多元logistic回归筛选独立预测因子并建立评分模型,采用ROC曲线评估评分模型及独立预测因子诊断RLN-LN转移的效能,采用Z检验比较曲线下面积(AUC)的差异。应用Hosmer-Lemeshow检验和校准曲线评估模型拟合度。结果:肿瘤位置、肿瘤长度、RLN-LN短径、短径/MPR最长径是RLN-LN转移的独立预测因子,其诊断RLN-LN转移的AUC分别为0.586、0.705、0.831、0.777。基于以上4个CT特征建立评分模型,评分模型诊断RLN-LN转移的AUC为0.903(95%CI 0.846~0.959),优于各单一CT特征(Z=5.812,P<0.001;Z=2.161,P=0.030;Z=2.929,P=0.003;Z=4.052,P<0.001)。拟合优度Hosmer-Lemeshow检验结果显示P=0.555,校准曲线提示评分模型预测RLN-LN转移风险与实际转移风险之间具有良好的一致性。结论:基于CT图像的评分模型有助于食管鳞癌RLN-LN转移状态危险分层。 相似文献
72.
《Brain & development》2021,43(10):1023-1028
BackgroundAromatic L-amino acid decarboxylase (AADC) deficiency, caused by a pathogenic variant in the dopa decarboxylase (DDC) gene, is a rare neurometabolic disorder in which catecholamine and serotonin are not synthesized. From a large number of reports, it has been recognized that most affected patients show severe developmental delay in a bedridden state and are unable to speak. On the other hand, patients with a mild phenotype with AADC deficiency have been reported, but they number only a few cases. Therefore, the variation of phenotypes of the disease appears to be broad, and it may be challenging to diagnose an atypical phenotype as AADC deficiency.Case reportWe report novel compound heterozygous variants in DDC (c.202G > A and c.254C > T) in two sisters, whose main complaint was mild developmental delay, by whole-exome sequencing (WES). Additionally, we describe their clinical features and provide an image that shows the variants located at different sites responsible for the catalysis of AADC in a three-dimensional structure. The patients were prescribed a Monoamine oxidase (MAO) inhibitor after diagnosis.InterpretationOur cases indicate that a comprehensive genomic approach helps to diagnose AADC deficiency with atypical features, and underscore the significance of understanding the variations of this disorder for diagnosis and appropriate treatment. 相似文献
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74.
《Brain stimulation》2021,14(6):1483-1485
Non-invasive brain stimulation techniques such as conventional transcranial direct current stimulation (tDCS) and high definition tDCS (HD-tDCS) are increasingly being used as add-on treatment options in schizophrenia and obsessive-compulsive disorder (OCD). This is reporting of the use of a novel accelerated, symptom-specific, add-on tDCS (combining conventional and high definition) protocol in a patient with both schizophrenia and OCD. The intervention showed clinical utility by reducing both schizophrenia and OCD symptoms. 相似文献
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77.
目的比较基因组拷贝数变异测序(CNV-seq)技术和染色体核型分析和在产前胎儿遗传学诊断中的应用价值。方法收集来我院有产前诊断指征进行羊水穿刺的259例孕妇,取材后,送检染色体核型分析和CNV-seq,比较两种方法在产前诊断中的优缺点。结果259例标本中,共诊断异常染色体核型及微缺失微重复23例,总阳性诊断率8.88%(23/259),CNV-seq结果显示,共有22例染色体拷贝数异常(12例三体+9例微缺失微重复+1例三倍体),检出率为8.49%;染色体核型分析结果显示为:17例染色体异常(12例三体+3例结构异常+1例嵌合型+1例三倍体),检出率为6.56%。此外还检出染色体多态7例。结论CNV-seq与染色体核型分析对于染色体非整倍体的检测效力一致,CNV-seq能检测染色体微缺失微重复,染色体核型分析则能诊断出三体具体核型,在怀疑性染色体异常时,建议行两者联合检测。 相似文献
78.
Sarah Hallas Andrea Nelson Susan O'Meara Una Adderley Pauline Meskell Jane Nixon Aonghus O'Loughlin Sebastian Probst Wael Tawfick Thomas Wild Georgina Gethin 《Journal of tissue viability》2021,30(3):317-323
BackgroundA venous leg ulcer is a chronic leg wound caused by poor venous blood circulation in the lower limbs. It is a recurring condition causing pain, malodour, reduced mobility, and depression. Randomised controlled trials evaluating treatments for venous leg ulcers provide important evidence to inform clinical decision-making. However, for findings to be useful, outcomes need to be clinically meaningful, consistently reported across trials, and fully reported. Research has identified the large number of outcomes reported in venous leg ulcer trials, impacting both synthesis of results, and clinical decision-making. To address this, a core outcome set will be developed. A core outcome set is an agreed standardised set of outcomes which should be, as a minimum, measured and reported in all trials which evaluate treatment effectiveness for a given indication. A core outcome set has the potential to reduce research waste, improve the utility of RCTs, reduce reporting bias, facilitate treatment comparisons across different sources of evidence and expedite the production of systematic reviews, meta-analyses and evidence-based clinical guidelines.AimThe aim of this project is to develop a core outcome set for research evaluating the effectiveness of interventions for treating venous leg ulceration.MethodsThrough a scoping review of the literature on venous leg ulceration, we will firstly identify a list of candidate outcome domains (broad categories in relation to what is being measured) from randomised controlled trials and qualitative research, and outcomes (specific methods in relation to what is being measured). In two further stages, we will use the resulting lists of outcome domains and outcomes to design two online surveys. A range of stakeholders will be invited to participate in the surveys and they will be asked to indicate which outcome domains and outcomes are most important and should be considered as core in future research reports. 相似文献
79.
Alan W. Freeman 《The Journal of neuroscience》2021,41(1):89
Motion perception is a vital part of our sensory repertoire in that it contributes to navigation, awareness of moving objects, and communication. Motion sense in carnivores and primates originates with primary visual cortical neurons selective for motion direction. More than 60 years after the discovery of these neurons, there is still no consensus on the mechanism underlying direction selectivity. This paper describes a model of the cat''s visual system in which direction selectivity results from the well-documented orientation selectivity of inhibitory neurons: inhomogeneities in the orientation preference map for inhibitory neurons leads to spatially asymmetric inhibition, and thus to direction selectivity. Stimulation of the model with a drifting grating shows that direction selectivity results from the relative timing of excitatory and inhibitory inputs to a neuron. Using a stationary contrast-reversing grating reveals that the inhibitory input is spatially displaced in the preferred direction relative to the excitatory input, and that this asymmetry leads to the timing difference. More generally, the model yields physiologically realistic estimates of the direction selectivity index, and it reproduces the critical finding with contrast-reversing gratings that response phase advances with grating spatial phase. It is concluded that a model based on intracortical inhibition can account well for the known properties of direction selectivity in carnivores and primates.SIGNIFICANCE STATEMENT Motion perception is vital for navigation, communication, and the awareness of moving objects. Motion sense depends on cortical neurons that are selective for motion direction, and this paper describes a model for the physiological mechanism underlying cortical direction selectivity. The essence of the model is that intracortical inhibition of a direction-selective cell is spatially inhomogeneous and therefore depends on whether a stimulus generates inhibition before or after reaching the cell''s receptive field: the response is weaker in the former than in the latter case. If the model is correct, it will contribute to the understanding of motion processing in carnivores and primates. 相似文献
80.
Yang Luan Yan Zhang Kai Cui Fan Li Baolong Qin Yajun Ruan Kun Tang Hongyang Jiang Hao Li Xiaoyi Yuan Zhuo Liu Xiaming Liu Gan Yu Shengfei Xu Ruibao Chen Huan Yang Xiaolin Guo Xiaoyong Zeng Zhong Chen Zhiqiang Chen Zhiquan Hu Xiaodong Song Zhihua Wang Shaogang Wang Jihong Liu Tao Wang 《Translational andrology and urology》2021,10(1):466
BackgroundTo introduce and determine the value of optimized strategies for the management of urological tube-related emergencies with increased incidence, complexity and operational risk during the global spread of coronavirus disease 2019 (COVID-19).MethodsAll emergent urological patients at Tongji Hospital, Wuhan, during the period of January 23 (the beginning of lockdown in Wuhan) to March 23, 2020, and the corresponding period in 2019 were recruited to form this study’s COVID-19 group and control group, respectively. Tongji Hospital has the most concentrated and strongest Chinese medical teams to treat the largest number of severe COVID-19 patients. Patients in the control group were routinely treated, while patients in the COVID-19 group were managed following the optimized principles and strategies. The case incidence for each type of tube-related emergency was recorded. Baseline characteristics and management outcomes (surgery time, secondary complex operation rate, readmission rate, COVID-19 infection rate) were analyzed and compared across the control and COVID-19 periods.ResultsThe total emergent urological patients during the COVID-19 period was 42, whereas during the control period, it was 124. The incidence of tube-related emergencies increased from 53% to 88% (P<0.001) during the COVID-19 period. In particular, the incidence of nephrostomy tube-related (31% vs. 15%, P=0.027) and single-J stent-related problems (19% vs. 6%, P=0.009) increased significantly. The mean surgery times across the two periods were comparable. The number of secondary complex operations increased from 12 (18%) to 14 (38%) (P=0.028) during the COVID 19-period. The number of 2-week postoperative readmission decreased from 10 (15%) to 1 (3%) (P=0.049). No participants contracted during the COVID-19 period.ConclusionsUrological tube-related emergencies have been found to have a higher incidence and require more complicated and dangerous operations during the COVID-19 pandemic. However, the optimized management strategies introduced in this study are efficient, and safe for both urologists and patients. 相似文献