EMRC和EMRL治疗上消化道早期癌及癌前病变

目的:探讨EMRC和EMRL两种EMR技术在上消化道早期癌及癌前病变中的临床应用价值。方法:18例病人(其中食管病变5例、胃内病变13例。超声内镜及病理检查早期胃癌1例、食管平滑肌瘤1例、增生性息肉7例、扁平腺瘤6例、不典型增生3例)。7例用EMRC、11例用EMRL技术进行了内镜下粘膜切除术。结果EMRC技术对食管平滑肌瘤、增生性息肉、扁平腺瘤、不典型增生的完全切除率分别为100%、100%、85.71%、85.71%,平均92.86%。而EMRL对胃早期胃癌,增生性息肉,扁平腺瘤,不典型增生的完全切除率分别为100%、100%、90.91%、90.91%,平均95.46%。结论EMRC和EMRL对上消化道早期癌、癌前期病变、黏膜下肿瘤及宽基息肉等均有较高的完全切除率。作为一项微创内镜技术,可替代部分胃肠道早期癌肿的外科手术治疗,降低治疗费用,且创伤性小,并发症少,疗效可靠,具有广阔的临床应用前景。     

Ki—67、P_(53)及Bcl—2在结肠锯齿状腺瘤中的表达

<正>良性结直肠上皮性息肉传统上被分为两种类型:增生性息肉和腺瘤。前者具柱状吸收细胞增多形成微乳头突入腺隐窝腔中使腔面呈锯齿状及肿胀的杯状细胞的特点,被认为不具有形成肿瘤的潜能。后者具腺腔呈指状、核深染、细胞排列成多层的特点,被认为是结肠癌的先兆。除此之外,在一种息肉具有以下特征:腺腔呈锯齿状、杯状细胞发育不全、腺隐窝上部核分裂像多见,上皮细胞内可见核仁,它既具有增生性息肉的特点结构又具有腺瘤的细胞学特征,这种混合性息肉是结肠直上皮性肿瘤的一种特殊亚型,称为锯齿状腺瘤。本研究比较这三种息肉Ki—67、P_(53)及Bcl—2的表达情况。     

基于改进ConvNeXt的COVID-19胸部图像分类

针对新型冠状病毒感染胸部 X-ray 图像分类任务数据集样本过少,现有的两阶段分类器和三阶段分类器模型对高纬度的图像特征提取效果差,模型训练慢等问题,提出一种基于 ConvNeXt 卷积神经网络改进的分类任务算法 ConvNeXt-AT。 ConvNeXt-AT 分类模型首先通过在 ConvNeXt Block 层添加混合域注意力机制 CBAM 来提高图像特征提取能力,不仅考虑了通道间的信息交互能力还考虑到了空间域上像素间的联系,得到 ConvNeXt-AT 模型;然后针对 X-ray 图片常见的泊松噪声使用全变差正则化方法对数据集进行降噪处理;最后在 COVID-19 公开的大型数据集共 21165 张图片进行对比实验。 实验结果表明,在训练数据集充分的情况下,改进的 ConvNeXt-AT 模型相较于常用分类模型 ResNet-50、MobileNet、EfficientNet 以及原 ConvNeXt-T 在准确率上分别提升了 2%、2. 7%、2. 1%、1. 9%。 最后通过 Grad-CAM 显示类激活图的图像可视化方法证明改进方法是可行的,模型具有很好的鲁棒性。     

一种基于改进YOLOv5s网络的结直肠腺瘤实时检测方法

为解决现有的基于深度学习的结直肠息肉检测算法计算复杂或检测精度较低,不能在速度和精度方面同时满足实时检测的问题,提出了一种基于单阶段目标检测网络YOLO(you only look once)v5s的结直肠腺瘤实时检测方法.在YOLOv5s的主干网中融入通道注意力机制,并以BCEWithLogitsLoss代替其原有的交叉熵损失函数BCELogits,以此提升网络性能.选取2 074张腺瘤图片和包含19 700帧的20段腺瘤视频,按照3∶1的比例构建结直肠腺瘤训练集和测试集.测试结果表明,结直肠腺瘤检测的平均精度为93.6%,检测速度为93帧/s,验证了该系统可以在肠镜的退镜过程中实时检测腺瘤性息肉,且具有较好的检测性能.     

多尺度光照估计和层次化分类的衣着颜色识别

衣着颜色是行人最显著的表观特征,在视频监控场景中极易受到光照变化的影响.为此,笔者提出了一种基于多尺度光照估计和层次化分类的衣着颜色识别方法.首先,提出一种多尺度局部反射统计的光照估计模型,通过该模型实现对偏色图像的光照矫正;其次,为了精确地识别衣着颜色,设计基于融合多颜色空间特征的层次化分类器;最后,在校园监控场景采集4 998张行人衣着图像(晚上2 052张,白天2 946张)进行对比实验.实验结果表明,该方法能有效提高监控视频中衣着颜色识别准确率且至少提高12.5%.     

基于改进YOLOv5模型的船舶焊缝缺陷检测方法

当前船舶焊缝缺陷检测主要是通过人工目视的手段检查焊缝的射线探伤图像进行的，存在耗时长、工作量大、效率低的问题，为此提出了一种基于改进YOLOv5模型的船舶焊缝缺陷检测方法.首先对1 152张船舶焊缝射线图像进行标注，建立船舶焊缝射线图像数据集；然后根据船舶焊缝缺陷几何尺寸小、特征不明显的特点，对YOLOv5模型进行改进.通过对图像进行正弦灰度变换，提高缺陷处的对比度.加入卷积注意力模块(CBAM),增大感兴趣区域的权重.增加检测尺度，提高对微小目标的检测精度.计算对比检测结果表明，使用改进的YOLOv5模型对船舶焊缝缺陷进行识别，使精确度从95.3%提高到98.4%,召回率从77.5%提高到77.9%,交并比为0.5时的平均精确度从81.5%提高到84.2%,证明该方法可以有效地改进船舶焊缝缺陷检测的效果.     

基于改进的Yolo v3模型的设备状态检测方法

提出一种基于改进的Yolo v3模型的设备状态检测方法,以实现精准的信号灯检测. 工作流程为:(1)通过图像采集设备获取信号灯图像并预处理;(2)通过改进的Yolo v3模型进行信号灯检测.其中改进的Yolo v3模型增加了特征图的加权融合步骤,提高了对小目标检测识别的性能.实验结果表明, 相比于原始Yolo v3模型,采用改进的Yolo v3 模型进行信号灯检测识别时能够取得更高的交并比,同时,模型的召回率和精度也有相应提升.     

内镜下高频电切胃息肉164例分析

目的 :探讨内镜下高频电切胃息肉的方法和效果。方法 :对 1 64例胃息肉进行组织学检查 ,其中对 1 3例无蒂大息肉可先在病变基底部粘膜下层分点注射 1∶ 1 0 0 0去甲肾上腺素生理盐水溶液 ,使病变明显隆起 ,然后再在内镜下用圈套分块切除。其余病例在内镜下用高频电切一次性摘除。结果 :1 64例胃息肉患者中 ,共摘除 1 71枚息肉。治疗无蒂大息肉 1 3例 ,2～ 3cm9例 ;3.1～ 4.0 cm3例 ;>4.1 cm1例。术后病理证实小凹上皮增生型息肉 73例 ( 4 4.5 % ) ,胃体腺型息肉 35例 ( 2 1 .4% ) ,炎性息肉和腺瘤性息肉分别为 41例 ( 2 5 .0 % )及 1 5例 ( 9.1 % )。 6、1 2、1 8月随访病例分别为96、67、38例 ,均未发现有复发。本组也未发生出血或穿孔等并发症。结论 :内镜下治疗胃部有蒂息肉或无蒂大息肉是安全有效的     

基于U-Net改进的内窥镜息肉图像分割算法

息肉图像的分割在临床医疗和计算机辅助诊断技术等领域具有广泛的研究和应用价值,但是就目前的研究和应用需求来看,准确的息肉分割仍然是一项挑战. 针对内窥镜息肉图像中出现的息肉与黏膜边界不清晰、息肉的大小和形状差异较大等影响分割质量的问题,该文提出了一种基于U-Net改进的息肉图像分割算法（SBF-Net）. 首先,在U-Net架构上引入了边界特征加强模块（BFEM）,考虑到息肉边界和内部区域的关键线索,该模块利用编码器高层特征生成额外的边界补充信息,在解码器阶段进行融合,提升模型处理边界特征的能力. 其次,该模型的解码器（GFBD）采用了从上至下逐步融合特征的方式,将编码器阶段的输出特征经过局部加强（LE）模块之后再逐步融合边界特征,这种多尺度特征融合方式有效缓解了编码器和解码器之间的语义差距问题. 最后,在后处理阶段采用测试时数据增强（TTA）来进一步对分割结果进行细化. 该模型在CVC-300、CVC-ClinicDB、Kvasir-SEG、CVC-ColonDB和ETIS-LaribPolypDB等5个公开数据集上进行了对比实验和消融实验,实验结果证明了该文所改进方法的有效性,并在内窥镜息肉图像上表现出更好的分割性能和更强的稳定性,为息肉图像的处理和分析提供了新的参考.     

幽门螺杆菌感染与胃息肉的相关分析

分析幽门螺杆菌(Hp)与不同病理类型胃息肉之间的相关性。回顾性分析2016年经胃镜确诊为胃息肉的住院患者临床资料,包括镜下分型、病理分型及幽门螺杆菌感染情况。130例患者中,炎性息肉88例(占68.21%),增生性息肉33例(25.58%),胃底腺息肉7例(4.65%),低分化腺癌2例(1.55%)。胃息肉患者以41-70岁年龄组为主(80%),息肉多位于胃体、胃窦(73.08%),病理类型以炎性与增生性息肉为主(80.76%),增生性息肉与炎性息肉的好发部位差异显著。全部息肉检出患者中Hp感染60例(46.15%),其中炎性息肉47例(占Hp感染息肉患者的78.33%),与增生性息肉比较差异有统计学意义。在本组病例中,炎性息肉、增生性息肉发生率高,好发年龄为41-70岁,炎性息肉好发于胃窦,增生性息肉好发于胃体。炎性息肉患者Hp感染率高,根除Hp的治疗可能抑制炎性息肉的发生。由于本次研究的局限性,尚不具有代表性,Hp与胃息肉的相关性仍需进一步完善。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that