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关键词： 深度学习   超声心动图   房间隔缺损   切面识别   双边滤波  

摘要： 针对超声心动图像质量差、噪声多,传统卷积神经网络架构对超声心动图像的学习能力有限、表达不充分的缺点,提出了一种基于标准切面识别的房间隔缺损(Atrial septal defect,ASD)智能辅助诊断模型.该模型通过对超声心动图像进行切面识别,充分融合其不同切面的语义特征,使得诊断的准确率得到明显提升.此外,还对其进行双边滤波保边去噪,并基于此模型搭建房间隔缺损智能辅助诊断系统(简称ASD辅助诊断系统).结果表明,该ASD辅助诊断系统的准确率高达97.8%,且与传统卷积神经网络相比大大降低了假阴性率.

关键词： 蒸压加气混凝土   隔墙板   砌块墙体  

摘要： 蒸压加气混凝土隔墙板是具有保温隔热性能强、施工效率高、施工成型质量优异等优良性能的绿色建材。以灵山岛金茂湾项目蒸压加气混凝土隔墙板施工应用为研究对象,通过与传统普通砌筑施工应用进行比较研究分析,主要分析内容如下:蒸压加气混凝土隔墙板材与传统普通砌筑材料外观尺寸偏差、性能要求差异,施工质量与劳动力计划分析,施工进度、成本分析。研究结果表明:在材料外观尺寸偏差、各性能要求方面不相上下,施工过程质量不可控因素少,便于现场管理,垂直平整度、成型效果优异,劳动力投入较少,施工效率高,成本可控,综合效益高,属于经济性墙体,具有良好的工程应用价值。

关键词： 菊花   阳台   花草   《诗经》  

摘要： 妈妈平日里侍弄花草,常常忘却门边放着的一盆尚未开放、不起眼的菊花。起初,我对它也没太多好感。别的花早开了,它却只有光秃秃的枝条懒懒地倚在门旁,微微散开,像蓬乱的头发。一个阳光明媚的下午,我静静地躺在阳台的摇椅上,沐浴阳光,欣赏阳台上的花草。不经意间,我的目光落在了那盆菊花上。在阳光的照射下,它那墨绿的茎叶变得浓翠欲滴;微风拂过,它开始扭动柔嫩的腰肢翩翩起舞。我联想到了《诗经》中的静女。

关键词： 伸缩缝施工   市政道路桥梁   道路桥梁施工  

摘要： 由于市政道路桥梁需要长期可靠运行,这就要求建设单位必须从长远发展的角度设计市政道路的施工方案,施工人员应按照方案要求,控制施工的各个环节,特别是各种施工技术的准确应用,从而减少外部因素的干扰,避免施工质量问题的发生。伸缩缝施工工艺受施工环境温度影响较大,伸缩缝施工也关系到市政道路的运营安全。因此,在实际伸缩缝施工中,要做好施工前的各项准备工作,准确应用切缝开槽技术,注意型钢变形的校核,做好后期伸缩缝的维护管理工作,从而提高伸缩缝的施工质量。

关键词： 改性沥青   桥梁伸缩缝   常见病害   养护要点  

摘要： 桥梁伸缩缝的存在是为了满足桥面变形需求,作为桥梁的重要组成部分之一,桥梁伸缩缝一般设置在梁端与桥台之间,需满足车辆平顺行驶、防止雨水渗透、易于检查养护等条件。日常桥梁伸缩缝的养护是维持其正常功能的基础条件,对于确保行车舒适度和行车安全具有重要意义,本文以近几年昆山市区三里桥、玉龙桥等几座桥梁为例,就改性沥青桥梁伸缩缝常见的一些问题及养护方法展开论述,期望可以为相关从业人员提供参考。

摘要： Using toric geometry we give an explicit construction of the compact steady solitons for pluriclosed flow first constructed in by the first author in 2019. This construction also reveals that these solitons are generalized Kahler in two distinct ways, with vanishing and nonvanishing Poisson structure. This gives the first examples of generalized Kahler structures with nonvanishing Poisson structure on nonstandard Hopf surfaces, completing the existence question for such structures. Moreover, this gives a complete answer to the existence question for generalized Kahler-Ricci solitons on compact complex surfaces. In the setting of generalized Kahler geometry with vanishing Poisson structure, we show that these solitons are unique. We show that these solitons are global attractors for the generalized Kahler-Ricci flow among metrics with maximal symmetry. (c) 2020 Wiley Periodicals LLC

关键词： basal insulin   initiation   type 2 diabetes  

摘要： Initiating insulin therapy with a basal insulin analogue has become a standard of care in the treatment of type 2 diabetes mellitus (T2DM). Despite increasing choices in pharmacological approaches, intensified glucose monitoring and improvements in quality of care, many patients do not achieve the desired level of glycaemic control. Although insulin therapy, when optimized, can help patients reach their glycaemic goals, there are barriers to treatment initiation on both the side of the patient and provider. Providers experience barriers based on their perceptions of patients' capabilities and concerns. They may lack the confidence to solve the practical problems of insulin therapy and avoid decisions they perceive as risky for their patients. In this study, we review recommendations for basal insulin initiation, focussing on glycaemic targets, titration, monitoring, and combination therapy with non-insulin anti-hyperglycaemic medications. We provide practical advice on how to address some of the key problems encountered in everyday clinical practice and give recommendations where there are gaps in knowledge or guidelines. We also discuss common challenges faced by people with T2DM, such as weight gain and hypoglycaemia, and how providers can address and overcome them.

关键词： Kaposi's sarcoma-associated herpesvirus (human herpesvirus type 8)   ORFK1   phylogenetic analysis   single base extension   subtypes  

摘要： Sequence analysis of the ORFK1 of human herpesvirus type 8 (HHV-8) allows the identification of six major subtypes (A-F), which are related to human migrations and the clinical progression of Kaposi's sarcoma. Sequencing and subsequent phylogenetic analysis of ORFK1 is considered to be the most reliable method for HHV-8 genotyping. However, it exhibits challenges and limitations. Herein, we designed and validated a single base extension (SBE) protocol for characterization of HHV-8 ORFK1 subtypes. A nested polymerase chain reaction (PCR) protocol was carried out to amplify a small 294-bp PCR product encompassing four single nucleotide polymorphisms at positions 360, 406, 465 and 527 of the HHV-8 genome. Finally, a multiplex SBE technique was developed and validated in 20 samples previously genotyped by phylogenetic analysis. The patterns obtained in this reaction could successfully discriminate between ORFK1 subtypes. The typing results obtained completely matched with those of the 'gold standard' method in all analysed samples. This method can reliably identify HHV-8 subtypes A, B and C, which are the most prevalent ones worldwide, and the remaining subtypes (D, E and F). SBE can be useful as an efficient, rapid and low-cost screening method for viral genotyping in a single tube, particularly samples with low-quality DNA, and with easy data interpretation.

摘要： Cell-free fetal DNA analysis has an established role in prenatal assessments. It serves as a source of fetal genetic material that is accessible non-invasively from maternal blood. Through the years, evidence has accumulated to show that cell-free fetal DNA molecules are derived from placental tissues, are mainly of short DNA fragments and have rapid post-delivery clearance profiles. But questions regarding how they come to being short molecules from placental cells and in which physical forms do they exist remained largely unanswered until recently. We now know that the distributions of ending sites of cell-free DNA molecules are non-random across the genome and bear correlations with the chromatin structures of cells from which they have originated. Such an insight offers ways to deduce the tissue-of-origin of these molecules. Besides, the physical nature and sequence characteristics of the ends of each cell-free DNA molecule provide tell-tale signs of how the DNA fragmentation processes are orchestrated by nuclease enzymes. These realizations offered opportunities to develop methods for enriching cell-free fetal DNA to facilitate non-invasive prenatal diagnostics. Here we aimed to collate what is known about the biological and physical characteristics of cell-free fetal DNA into one article and explain the implications of these observations.

关键词： Human fetal testis   Sertoli cells   Stem cell factor   Spermatogonial stem cells   beta-estradiol  

摘要： Background Mammalian spermatogenesis is responsible for male fertility and is supported by the self-renewal and differentiation of spermatogonial stem cells (SSCs). Sertoli cells provide a supportive microenvironment for SSCs, in part by the production of stem cell factor (SCF), which is a potent regulator of spermatogonia proliferation and survival. Methods We investigated the novel role of beta-estradiol in modulating the proliferation and apoptosis of fetal SSCs via the regulation of SCF secretion in Sertoli cells isolated from human fetal testes. The proliferation of SSCs in the co-culture system was determined by colony formation and BrdU incorporation assays. TUNEL assay was used to measure SSC apoptosis in co-culture in response to treatment with control, beta-estradiol, or the combination of beta-estradiol and the estrogen receptor inhibitor ICI 182780. Results In the system with purified human fetal Sertoli cells (MIS+/c-Kit-/AP-), beta-estradiol upregulated the production of SCF in a dose- and time-dependent manner. In the co-culture system of primary human fetal SSCs (c-Kit+/SSEA-4+/Oct-4+/AP+) and Sertoli cells (MIS+), beta-estradiol markedly increased the proliferation of SSCs. Moreover, SSC apoptosis was significantly inhibited by beta-estradiol and was completely reversed by the combination of beta-estradiol and ICI 182780. Conclusion Here we report, for the first time, that beta-estradiol can induce the increase of SCF expression in human fetal Sertoli cells and regulates the growth and survival of human fetal SSCs. These novel findings provide new perspectives on the current understanding of the role of estrogen in human spermatogenesis.