基于自注意力的双通路全脊柱 X 光图像分割模型

全脊柱X光图像（包含脊柱、骶骨及髂骨）分割是目前脊椎疾病智能诊断中首要关键的环节。针对U-Net语义分割算法在全脊柱X光图像多区域分割精度较差的问题,提出一种双通道语义分割算法DAU-Net,通过空间通道与语义通道分别学习空间信息特征与图像语义特征,并在解码器端对两类特征进行融合,获取脊柱X光图像中更精准的分割边界。在空间通道中,使用空洞卷积及残差模块扩大视野域并保留更多远端特征信息。此外,将自注意力机制引入语义通道,并设计不同的自注意力编码与自注意力解码模块构建全局关联信息,实现对多个目标骨骼区域语义分割。实验结果表明,DAU-Net能够有效提高脊柱X光图像上的分割精度,相比U-Net、ResU-Net、Attention U-Net、U-Net++,Dice系数分别提高4.00%、1.90%、4.60%、1.19%。     

肾脏缺血再灌注损伤中肾小球的改变与NO的作用

肾缺血再灌注(I-R)损伤是临床常见的病理过程,肾I-R后具有肾小球损伤,一氧化氮(NO)对肾I-R后的肾小球滤过率、肾血流量的调节以及肾小球滤过膜通透性的改变都发挥着一定的作用,具有重要的病理生理意义.     

膜性肾小球肾炎重复性穿刺的病理观察

对13例膜性肾小球肾炎进行重复性穿刺,分别进行光镜、免疫荧光及电镜观察。结果表明,膜性肾小球肾炎为长期缓慢的病理过程,基底膜的改变比其他组织病理损伤显著。     

轻链肾病的病理学特点

目的 探讨轻链肾病(1ight chain nephropathy,LCN)的病理学特点及其诊断方法。方法 对7例LCN进行了系统的光镜、免疫荧光及透射电镜检查,并进行轻链蛋白(κ、λ)的免疫荧光和免疫电镜标记。结果 7例的光镜表现不一,3例系膜结节状硬化性肾小球病,1例系膜轻至中度增生;其余3例为管型肾病,肾小球病变轻微。免疫荧光检查：7例均可见单一品种的轻链蛋白在肾小球系膜区团块状,及肾小球基底膜、肾小管基底膜和小血管壁呈线性沉积。透射电镜检查可见肾小球系膜区和基底膜内侧、肾小管基底膜外侧及小血管壁的颗粒状电子致密物沉积。免疫电镜标记显示,肾小球基底膜内侧和系膜区、肾小管基底膜外侧及小血管壁的颗粒状沉积物均可被单一品种轻链蛋白(5例κ,2例λ)标记。结论 典型的LCN呈系膜结节状硬化性肾小球病,电镜观察到LCN的特征性超微结构改变具有诊断意义,结合轻链蛋白(κ、λ)的免疫荧光或免疫电镜检查可进一步确诊,尤其对光镜病变不明显的LCN更有意义。     

一种利用直方图特征峰的肾小球图像分割方法

根据肾小球医学图像的特点 ,提出了一种新的基于直方图特征峰的图像分割方法。通过定位图像的特征峰 ,从而有效地对肾小球医学图像进行阈值化。经实验证明 ,本文提出的算法能快速、准确地分割肾小球图像。     

尿FDP和Alb在CGN和NS检测的临床应用及相关性分析

目前已知 ,引起慢性肾小球肾炎 (CGN)和肾病综合征(NS)主要是自身免疫反应。由于自身免疫反应引起肾小球基底膜的损伤 ,进行导致肾小球滤过膜通透性的增加 ,使大量的白蛋白 (Alb)在尿中出现 ,从而引发蛋白尿。肾小球的受损、滤过膜通透性增加继发引起肾小球微血管内凝血 ,进一步激活纤溶系统导致患者尿中纤维蛋白降解产物 (FDP)增高[1] 。本文通过对CGN和NS患者尿中Alb和FDP含量的测定及其相关性分析 ,旨在明确Alb和FDP在CGN和NS的临床诊断中应用价值。对象和方法一、对象 :(一 )正常对照组 :30例 (男 16 ,女 14 ) ,平均年龄 39 …     

IgA肾病足突融合和疾病严重性

目的　 Ig A肾病是一种与肾小球系膜细胞增生及 Ig A沉积有关的常见的进展性肾小球疾病。当前研究的设计为调查 Ig A肾病患者病变严重程度在功能上与形态上一致性改变。方法　通过观察 17例成年 Ig A肾病患者菊粉糖、对氨基马尿酸 (PAH)、 3H-非科尔的清除率和形态测定方法来研究肾小球的血液动力学、选择性滤过及超微结构。大分子物质通过半透膜渗透的数学模型用作特征性的肾小球选择性滤过。对照为 14名健康活体供肾者和 12名健康志愿者。结果　患者在病变严重程度上存在差异 ,但作为肾小球滤过率 (GFR)降低和蛋白尿排泄增加的一组…     

基于空洞空间卷积池化金字塔结构和注意力机制的全卷积残差网络磨玻璃肺结节分割方法EI北大核心CSCD

准确分割磨玻璃肺结节(GGN)具有重要临床意义。针对电子计算机断层扫描(CT)图像中GGN边界模糊、形状不规则、强度不均匀等特点导致其分割困难的问题,本文提出一种全卷积残差网络算法,即基于空洞空间卷积池化金字塔结构和注意力机制的残差网络(ResAANet)算法。该网络算法利用空洞空间卷积池化金字塔(ASPP)结构扩大特征图感受野,提取更充分的目标特征,并采用注意力机制、残差连接和长跳跃连接充分保留卷积层提取的GGN敏感特征。首先,用上海市胸科医院收集的565个GGN对ResAANet进行全监督训练、验证,得到稳定的模型;然后,利用收集的另84个GGN和肺部图像数据库联盟(LIDC)公共数据库中145个GGN分别测试模型得到粗分割结果;最后,用连通域分析方法去除假阳性区域得到优化结果。本文所提算法在采集的临床数据和LIDC测试集上的戴斯相似系数(DSC)达到83.46%、83.26%,平均重合度(IoU)达到72.39%、71.56%,切片分割效率达到0.1 s/张。与其他算法相比,本文提出的方法能准确、快速分割GGN,且具有较好的稳健性,可以为医生提供结节大小、密度等重要信息,辅助医生后续的诊断和治疗。     

基于滑动块的深度卷积神经网络乳腺X线摄影图像肿块分割算法

目的:提出一种基于滑动块的深度卷积神经网络局部分类、整图乳腺肿块分割的算法,为临床诊断提供有效的肿块形态特征。方法:首先通过区域生长算法和膨胀算法提取患者乳腺区域,并进行数据归一化操作。为了得到每一个像素位置上的诊断信息,在图像的对应位置中滑动提取肿块类及非肿块类图像块,根据卷积神经网络提取其中的纹理信息并对图像块进行分类。通过整合图像块的预测分类结果,进行由粗到细的肿块分割,获得乳腺整图中像素级别的肿块分割。结果:通过比较先进的深度卷积神经网络模型,本文算法滑动块分类结果DenseNet模型下准确率达到96.71%,乳腺X线摄影图像全图肿块分割结果F1-score最优为83.49%。结论:本算法可以分割出乳腺X线摄影图像中的肿块,为后续的乳腺病灶诊断提供可靠的基础。     

基于深度卷积神经网络的肾透明细胞癌细胞核分割

肾透明细胞癌病理图像中细胞核的形态和位置信息对肾癌的良恶性分级诊断具有重要意义,为提高肾透明细胞癌细胞核分割的质量,本研究提出了基于深度卷积神经网络的细胞核分割方法。首先,根据标定的病理图像中细胞核轮廓,构建细胞核分割样本集;然后,深度卷积神经网络通过隐式特征学习对细胞核分割模型进行训练,避免人为设计特征;最后,利用细胞核分割模型对病理图像进行逐像素分割。实验结果表明,深度卷积神经网络的细胞核分割算法在肾透明细胞癌细胞核分割的像素准确率高达90.33%,细胞核分割性能稳定,深度卷积神经网络强大的鲁棒性和适应性使得肾透明细胞癌细胞核自动分割具有可能。     

Basement membrane charge in human glomerular disease

Fixed anionic charges in the mammalian glomerulus, on both the basement membrane and the epithelial cell foot processes, are believed to form an important part of the glomerular filtration barrier. There is good evidence that their loss causes proteinuria. The charges can be visualized ultrastructurally using cationic dyes, but the requirement of these techniques for perfusion or immersion of fresh tissue has largely confined such studies to experimental models. We have extended the widely used polyethyleneimine technique, to study the charge of glomerular basement membranes in human tissue reprocessed out of paraffin blocks up to 10 years old. We studied selected cases of glomerular disease, where the diagnosis was not in any doubt. In the majority of diseases studied, a continuous charge layer persisted despite severe abnormalities of the basement membrane. Two exceptions were found. In amyloidosis, accumulation of fibrils was associated with a considerable decrease or loss of stainable basement membrane charge. In S.L.E., numerous small defects in the charge layer were noted. The persistence of charge is contrary to reported findings in several animal models of glomerular disease, including puromycin nephrosis, Heymann nephritis and streptozotocin diabetes. Although this method is not subject to precise quantitative analysis, we conclude that in the majority of cases, proteinuria in man is not caused by an extensive loss of glomerular basement membrane anionic charge.     

Identification of an electron densification of the glomerular basement membrane in renal biopsy specimens

Ultrastructural examination of renal biopsy specimens is often necessary to establish a diagnosis. We have noted, in some renal biopsies, that normal-appearing glomerular basement membrane (GBM) shows an electron densification. The aim of this study was to describe this phenomenon and assess the degree of its occurrence. We reviewed ultrastructural pathology records of 153 renal biopsy patients with special reference to the careful examination of the electron micrographs. Of these, 28 cases (18%) showed a definite and homogeneous electron densification of normal-appearing GBM in the glomeruli. The pathological diagnosis in these cases was IgA nephropathy in 15, minimal change nephrotic syndrome in 6, interstitial nephritis in 3, membranoproliferative glomerulonephritis in 2, and nephritis of Henoch-Schonlein purpura and membranous nephropathy in 1 case each. In addition, frequent deposition of IgG without C3 in the GBM (86%) and glomerular endothelial cell edema (96%) were observed. No apparent correlation could be ascertained between the presence of the electron densification and pathological diagnosis. It is suggested that electron densification of the GBM may be caused by the penetration of some electron-dense materials into the GBM as a result of an abnormality in the glomerular filtration barrier and that this could be considered as a sign of altered properties of the lamina densa.     

Murine lupus nephritis. A structure-function study

This report examines the correlation between glomerular injury and glomerular dysfunction in murine lupus nephritis. Glomerular filtration rate was measured by the clearance of inulin in conscious NZB/W female mice and shown to vary 12-fold in the animals tested. Detailed morphometric measurements were made on the perfused fixed kidneys. As disease progressed the surface density (Sv) of the open capillary loops decreased by 73%. This drop in Sv correlated with a 4-fold increase in mean glomerular volume (MGV, r = -0.79, p less than 0.0001). The "compensating" increase in MGV maintained or increased filtration surface area despite the loss of some capillary loops to proliferating and/or infiltrating cells. Filtration slit length/glomerulus and the filtration slit number/micron glomerular basement membrane varied 10-fold and were found to correlate directly with glomerular filtration rate (r = 0.64, p less than 0.0007 and r = 0.70, p less than 0.0001, respectively). When linear and multiple regression analyses were applied, all other structural measures, including filtration surface area, correlated with glomerular filtration rate poorly if at all. Glomerular permselective dysfunction (proteinuria) was measured as the fractional clearance of albumin (fractional clearance of albumin) and of IgG. Stepwise multiple regression analysis revealed the percentage of the glomerular basement membrane occupied by dense deposits, slit number/glomerular basement membrane, and glomerular basement membrane thickness statistically explained most (81%) of the variation in fractional clearance of albumin and IgG. These results suggest that epithelial slit length is the most important structural determinant of GFR and that the increase in MGV maintains filtration surface area despite evidence of an extensive inflammatory insult. The mechanism(s) of proteinuria in this model of lupus nephritis are consistent with either a focal increase in GBM permeability due to immune deposits and/or a diffuse increase in permeability due to GBM charge neutralization. The study provides insight as to why previous structure-function reports failed to find correlates of glomerular injury to glomerular dysfunction.     

小鼠肾血管球滤过膜发育的电镜研究

目的研究发育中小鼠血管球滤过膜的变化。方法应用透射电镜观察胚胎和新生小鼠血管球滤过膜的超微结构。结果在肾小体的发育过程中,足细胞形状明显变薄,足突数量逐渐增多,其形状逐渐窄小,足突间裂孔和裂孔膜出现;足细胞下、内皮细胞下先后出现基膜,而后两种基膜融合形成一层较厚的基膜。随着毛细血管袢的不断增生,在足细胞下方出现新合成的环状或袋状的基膜片段;内皮细胞形状也明显变薄。出现大量内皮孔。结论在小鼠肾小体的发育过程中,足细胞和内皮细胞逐渐分化成熟,基膜最早来源于足细胞。随后内皮也参与合成基膜,发育晚期基膜的合成和更新主要由足细胞来完成。     

大鼠肾小体发育中滤过屏障超微结构的演变

目的:探讨大鼠肾小体发育中滤过屏障超微结构的变化规律。方法:采用光镜、电镜技术,并结合体视学分析方法,对不同发育阶段大鼠滤过屏障超微结构的变化进行形态学观察和体视学测量。结果:在肾小体发育过程中,足细胞和内皮细胞的形状逐渐低平,内皮孔增多,足突及裂孔大量分化增多;足细胞下先出现电子密度较低的基膜,随后内皮细胞下才出现基膜,以后,二者融合形成一层电子密度较高的血管球基膜。结论:在大鼠肾小体的发育过程中,足细胞比内皮细胞先分泌基膜,然后二者融合形成血管球基膜。     

High-Resolution Ultrastructural Study of the Rat Glomerular Basement Membrane in Aminonucleoside Nephrosis

In the initial stages of aminonucleoside nephrosis, functional alterations in the glomerular basement membrane occur, as evidenced by the development of proteinuria. However, it has not been possible to observe important ultrastructural modifications at the level of the basement membrane, probably because the changes are taking place at the molecular level. In this study, by the use of high-resolution electron microscopy, an attempt was made to evaluate such changes in rat glomerular basement membrane during acute aminonucleoside nephrosis. As previously reported, in control animals the glomerular basement membrane is composed of a network of 4-nm-wide irregular anastomosing strands, referred to as “cords,” which are known to contain a core filament of type IV collagen surrounded by a “sheath” of other components, such as laminin and heparan sulfate proteoglycan (HSPG). The most conspicuous ultrastructural alteration of the nephrotic glomerular basement membrane, recognizable only at high magnification, is that the cords were denuded leaving only the core filament through the loss of the sheath material. Thus, the cord network was transformed, with the progress of pathological conditions, into a network of fine filaments. On the other hand, abundance and distribution of HSPG molecules known to be present in the form of 4.5- to 5-nm-wide ribbon-like “double tracks,” were found to be similar in control and nephrotic tissues. Since HSPG is one of the charge proteins of the basement membrane, the little changes observed for HSPG are difficult to interpret in view of reported decreases in basement membrane anionic sites in nephrosis. In conclusion, the glomerular basement membrane in aminonucleoside nephrosis loses its cord network components and replaces them with a more perforated network, which could be a cause for the increased permeability of this basement membrane.     

足细胞上皮间质转分化研究

足细胞是肾小球滤过膜的重要组成部分,在维持肾小球正常滤过功能方面起着至关重要的作用。足细胞上皮间质转分化（EMT）是多种慢性肾脏疾病蛋白尿产生及疾病进展的重要病理机制。减轻足细胞EMT已经成为慢性肾脏疾病防治研究的热点。基于此,本文主要就足细胞的生理特点、EMT病理过程及相关信号通路作一综述。     

Molecular sieve of the rat glomerular basement membrane: a transmission electron microscopic study of enzyme-treated specimens

Isolated rat glomerular basement membrane was treated with elastase and observed by transmission electron microscopy. The treatment with elastase revealed the fundamental structure of the glomerular basement membrane quite clearly, and enabled the observation of a sieve structure within the glomerular basement membrane. This sieve structure may play a major role in the filtration of blood as well as in the production of urine. Treatment with antibody showed that the sieve was mainly constituted of type IV collagen.     

Prognostic significance of glomerular and tubulointerstitial morphometry in idiopathic membranous nephropathy

The purpose of our study was to investigate the prognostic value of clinical and pathological, in particular glomerular and tubulointerstitial morphometric variables in idiopathic membranous nephropathy (IMN). We prospectively followed 60 Caucasian patients diagnosed with idiopathic membranous nephropathy for at least 2 years or until primary outcome (≥50% permanent decrease in estimated glomerular filtration rate or death). Glomerular and tubulointerstitial morphometric variables at the time of renal biopsy were analyzed with respect to this outcome. Univariate analysis revealed that significant negative prognostic factors for this outcome were higher cholesterol and smaller albumin concentrations, higher creatinine and maximal 24-h proteinuria, higher grade of nephroangiosclerosis, higher glomerular basement membrane thickness and glomerulopathy index, higher interstitial fibrosis and tubular atrophy percentage and higher injury score. In multivariate analysis, only the maximal 24-h proteinuria and interstitial fibrosis and tubular atrophy percentage were independent predictors of this outcome. The results suggest that morphometric analysis, mainly quantitative measurement of interstitial fibrosis and tubular atrophy percentage, injury score, glomerular basement membrane thickness and glomerulopathy index could be used as an additional method for risk stratification of patients with idiopathic membranous nephropathy.