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1.
目的 评估基于MR T2WI影像组学模型产前预测胎盘植入性病变(PAS)的价值。方法 回顾性分析241例孕妇及胎儿MRI,其中116例PAS、125例无PAS。按7:3比例将其分为训练集(n=168)和验证集(n=73),于训练集提取并筛选半傅立叶采集单次激发快速自旋回波(HASTE)及真实稳态进动快速成像(TrueFISP)序列图像的影像组学特征,构建预测PAS的影像组学模型,并以回归分析方法构建临床模型、影像组学模型及临床-影像组学模型。采用校准曲线和受试者工作特征(ROC)曲线分析模型的效能,以决策曲线分析(DCA)评估其临床实用性。结果 对各序列图像分别提取1 130个影像组学特征,经LASSO回归等处理后,各筛选出9个影像组学特征,用于构建预测PAS的HASTE及TrueFISP影像组学模型。ROC曲线显示,临床模型、HASTE影像组学模型及TrueFISP影像组学模型在验证集中诊断PAS的曲线下面积(AUC)分别为0.882、0.968和0.930(P均>0.05);HASTE联合TrueFISP影像组学模型的AUC为0.990,高于临床(Z=-2.36,P=0.02)、HASTE影像组学(Z=-2.48,P=0.02)及TrueFISP影像组学模型(Z=-2.43,P=0.02);临床-HASTE-TrueFISP影像组学模型的AUC为0.995,与HASTE联合TrueFISP影像组学模型差异无统计学意义(Z=-0.85,P=0.40),高于HASTE或TrueFISP影像组学模型(Z=-2.64、-2.47,P均<0.05)。临床模型之外,各模型在验证集数据中的校准度均较好;阈值取0~0.6时,其在验证集的临床净获益均大于临床模型。结论 基于产前HASTE及TrueFISP序列图像的联合影像组学模型有助于准确预测PAS。  相似文献   

2.
目的 观察基于MR-T2WI影像组学模型预测宫颈鳞癌临床分期的价值。方法 对159例经术后或活检病理证实的宫颈鳞癌患者采集盆部MRI,根据国际妇产科联盟(FIGO)分期系统及病理结果分为早期组(ⅠB~ⅡA期,n=73)和晚期组(ⅡB~Ⅳ期,n=86)。按照7 :3比例将患者随机分为训练集(n=113)和验证集(n=46)。训练集包括52例早期、61例晚期宫颈鳞癌,验证集含21例早期及25例晚期宫颈鳞癌。提取轴位T2WI中病灶的影像组学特征,以最大相关最小冗余和最小绝对收缩选择算子回归分析方法筛选最优影像组学特征,构建预测早、晚期宫颈鳞癌的影像组学模型。分析影像组学模型的拟合优度,采用受试者工作特征(ROC)曲线评估模型的预测效能,以决策曲线分析(DCA)评估模型的临床应用价值。结果 共提取396个影像组学特征,最终筛选11个最优影像组学特征,并以之构建预测早、晚期宫颈鳞癌的影像组学模型。影像组学模型在训练集和验证集中的拟合优度均佳(χ2=2.68、8.87,P均>0.05);其在训练集及验证集中的曲线下面积(AUC)均为0.80。DCA显示,阈值取0.10~1.00时,影像组学模型的净收益较大。结论 基于MR-T2WI的影像组学模型对预测宫颈鳞癌临床分期具有较高价值。  相似文献   

3.
目的 观察瘤内及瘤周表观弥散系数(ADC)影像组学特征预测髓母细胞瘤(MB)患儿预后的价值。方法 回顾性分析74例MB患儿资料,根据术后2年随访结果将其分为进展组(n=29)及无进展组(n=45),并按6:4比例分为训练集(n=44)或验证集(n=30)。基于ADC图提取并筛选瘤内及瘤周影像组学特征,分别建立瘤内、瘤周及瘤内+瘤周影像组学模型,并以之结合临床及常规影像学特征建立联合模型;比较各模型预测MB患儿预后的效能。结果 训练集中,临床-常规影像-瘤周影像组学模型、临床-常规影像-瘤内+瘤周影像组学模型曲线下面积(AUC)均大于单一瘤周影像组学模型(P均<0.05);验证集中,临床-常规影像学-瘤内+瘤周影像组学模型的AUC最大,但与其他模型差异均无统计学意义(P均>0.05)。结论 瘤内及瘤周ADC影像组学特征可用于预测MB患儿预后;联合临床及常规影像学特征或有助于提高预测效能。  相似文献   

4.
目的 比较增强CT模型与影像组学模型预测肾透明细胞癌(ccRCC)WHO/ISUP分级的效能。方法 回顾性分析131例经病理确诊ccRCC患者,按照3 ∶ 2比例分层抽样分为训练集(n=78)和验证集(n=53)。根据2016版肾癌WHO/ISUP病理分级标准,以Ⅰ~Ⅱ级为低级别、Ⅲ~Ⅳ级为高级别ccRCC。训练集55例低级别、23例高级别ccRCC;验证集37例低级别、16例高级别ccRCC。以训练集构建增强CT模型及影像组学模型预测ccRCC级别,于验证集加以验证,比较其诊断效能。结果 增强CT模型在训练集及验证集预测高、低级别ccRCC的曲线下面积(AUC)分别为0.89及0.76,敏感度分别0.83及0.56,特异度分别为0.84及0.87;影像组学模型的AUC分别为0.98及0.85,敏感度分别0.96及0.91,特异度分别为0.75及0.84。训练集中影像组学模型的AUC大于增强CT模型(Z=2.05,P<0.05),验证集中二者AUC差异无统计学意义(Z=0.95,P=0.34)。决策曲线分析结果显示高风险概率阈值为0.08~1.00时,影像组学模型净获益高于增强CT模型。结论 影像组学模型预测ccRCC WHO/ISUP分级的效能优于增强CT模型。  相似文献   

5.
目的 评价临床、CT影像组学及融合模型预测肝细胞癌(HCC)分化程度的可行性。方法 纳入330例HCC患者,根据病理所见分化程度分为高分化组(n=85)、中分化组(n=161)及低分化组(n=84),比较组间临床资料及CT征象差异。按3∶1比例随机将各组分为训练集及测试集。提取训练集CT影像组学特征,构建临床模型、影像组学模型及融合模型。绘制受试者工作特征(ROC)曲线,计算曲线下面积(AUC),评估各模型鉴别不同分化程度HCC的效能。结果 共纳入352个CT影像组学特征,109个来自高、中分化HCC,84个来自中、低分化HCC,159个来自高、低分化HCC。临床模型鉴别高、低分化HCC的AUC为0.85;CT影像组学模型鉴别高分化与中、低分化HCC的AUC分别为0.80及0.79;融合模型鉴别高、低分化HCC的AUC为0.88。结论 临床、CT影像组学及融合模型预测高、低分化HCC的效能均较高。CT影像组学模型可较好地预测高、中分化HCC。  相似文献   

6.
目的 分析基于双能量CT影像组学模型术前预测进展期胃腺癌短径≥0.6 cm淋巴结转移(LNM)的价值。方法 回顾性分析经手术切除的进展期胃腺癌患者,根据病理结果纳入36例pN3期114枚转移淋巴结(转移组)和26例pN0期65枚非转移淋巴结(非转移组),入组淋巴结短径均≥0.6 cm,将淋巴结分为训练集(n=125)和验证集(n=54)。对比组间原发肿瘤及淋巴结CT特征,采用广义估计方程(GEE)构建临床模型。提取静脉期融合图和碘图中的淋巴结影像组学特征,以组内相关系数(ICC)检验和Boruta算法筛选特征,构建影像组学模型,采用受试者工作特征(ROC)曲线和决策曲线分析(DCA)评价模型的诊断效能和临床收益。结果 单因素及多因素GEE分析显示,原发肿瘤部位及最大径、淋巴结边缘及脂肪分数为LNM独立预测因素(P均<0.05),以之构建的临床模型预测训练集和验证集LNM的曲线下面积(AUC)分别为0.74和0.76。经ICC检验(ICC>0.8)及Boruta算法筛选,最终保留27个影像组学特征;以之建立的影像组学模型预测训练集和验证集LNM的AUC分别为0.99和0.98,均高于临床模型(P均<0.01),且临床收益更优。结论 基于双能量CT影像组学模型术前预测进展期胃腺癌短径≥0.6 cm LNM具有较高价值。  相似文献   

7.
目的 评估基于术前腹部增强CT影像组学模型预测胰十二指肠切除术(PD)术后胰瘘(POPF)的价值。方法 回顾性分析252例接受PD患者的术前腹部增强CT资料,按7:3比例将其分为训练集(n=177)和验证集(n=75)。于训练集增强静脉期CT图像中勾画胰腺实质作为感兴趣容积(VOI),提取其影像组学特征,并筛选最优特征建立影像组学模型;绘制模型预测PD术后POPF的受试者工作特征(ROC)曲线,计算曲线下面积(AUC),评价模型预测效能;以验证集数据进行验证。结果 共选出14个最优影像组学特征用于构建影像组学模型。影像组学模型在训练集和验证集的AUC分别为0.82[95%CI(0.76,0.88)]和0.82[95%CI(0.72,0.91)]。结论 基于术前增强CT影像组学模型能有效预测PD术后POPF。  相似文献   

8.
基于CT影像组学术前预测胃癌淋巴血管侵犯   总被引:1,自引:1,他引:1  
目的 探讨基于CT影像组学术前预测胃癌淋巴血管侵犯的价值。方法 回顾性收集经手术病理证实的181例胃癌患者,将其随机分为训练集(n=120)和验证集(n=61)。首先基于增强CT静脉期图像分割肿瘤区域并提取影像组学特征;然后利用训练集筛选与淋巴血管侵犯相关特征,构建影像组学标签;最后基于验证集验证模型,采用ROC曲线及校准曲线评估模型的预测效能及拟合度。结果 最终提取7个与胃癌淋巴管血管侵犯最相关的影像组学特征构建影像组学标签,其在训练集的ROC曲线AUC为0.742[P=0.001,95%CI(0.652,0.831)],验证集AUC为0.727[P=0.002,95%CI(0.593,0.853)]。基于训练集所得最优阈值为0.422,模型在训练集中的准确率、敏感度和特异度分别为0.708、0.586、0.806,将此阈值用于验证集,其准确率、敏感度和特异度为0.689、0.519、0.824。校准曲线显示影像组学标签在训练集及验证集均具有较好的拟合度(P均>0.05)。结论 CT影像组学可作为预测胃癌术前淋巴血管侵犯提供的全新的无创影像学方法。  相似文献   

9.
目的 观察垂体相关临床及MRI影像组学特征联合列线图鉴别特发性中枢性性早熟(ICPP)与单纯乳房早发育(PT)的价值。方法 纳入67例ICPP及51例PT共118例患儿,按照7 ∶ 3比例随机分为训练集(n=83)和验证集(n=35),记录其垂体相关临床资料,以多因素logistic回归分析筛选并建立临床模型。采集垂体MRI,基于矢状位T1WI提取垂体影像组学特征,以最大相关最小冗余、最小绝对收缩和选择算子及多因素logistic回归筛选最佳影像组学特征,构建影像组学模型。联合应用临床、MRI及影像组学特征构建列线图模型。绘制受试者工作特征曲线,评估模型鉴别诊断效能;以决策曲线分析(DCA)观察临床获益度。结果 训练集ICPP与PT患儿年龄、骨龄、体质量、黄体生成素(LH)基础值、卵泡刺激素基础值及垂体高度差异均有统计学意义(P均<0.05)。骨龄及LH基础值是鉴别ICPP与PT的独立因素(OR=1.807、1.422,P均<0.05),以之建立的临床模型鉴别训练集、验证集ICPP与PT的曲线下面积(AUC)分别为0.849和0.812。共提取垂体1 781个影像组学特征,于其中筛选出1个形态特征、1个一阶特征及1个灰度区域大小矩阵特征建立影像组学模型,其鉴别训练集和验证集ICPP与PT的AUC分别为0.956和0.947。基于最终得出的2个临床及3个垂体MRI影像组学特征构建的列线图模型鉴别训练集、验证集ICPP与PT的AUC分别为0.981、0.977,均优于临床模型(P均<0.05),而与影像组学模型差异无统计学意义(P均>0.05)。一定危险阈值范围内,列线图模型净收益最大。结论 基于垂体相关临床及MRI影像组学特征建立的联合列线图模型用于鉴别ICPP与PT具有较高价值。  相似文献   

10.
目的 观察增强CT影像组学模型术前预测胃腺癌淋巴结转移(LNM)的价值。方法 回顾性分析193例经术后病理证实的单发胃腺癌的腹部双期增强CT资料,将其分为训练集(n=97)和验证集(n=96),比较LNM (+)与LNM (-)肿瘤CT表现的差异。分别于增强动脉期和静脉期CT提取病灶影像组学特征,构建相应影像组学标签;将单因素分析有统计学意义的CT参数及其影像组学标签纳入多因素logistic回归分析,筛选胃腺癌LNM的独立预测因素,分别建立临床模型及影像组学列线图。采用受试者工作特征(ROC)曲线评估各模型预测胃腺癌LNM的效能,计算曲线下面积(AUC),比较其差异。结果 训练集含54例LNM (+)和43例LNM (-),验证集含58例LNM (+)和38例LNM (-)。LNM (+)患者肿瘤厚度和阳性淋巴结占比均高于LNM (-)者(P均<0.05)。肿瘤厚度及淋巴结状态均为LNM的独立预测因素(P均<0.01)并用于构建临床模型。淋巴结状态和静脉期影像组学标签是胃腺癌LNM的独立预测因素(P均<0.01),以之构建的影像组学列线图在训练集和验证集中的AUC分别为0.810和0.778,与临床模型AUC差异均无统计学意义(0.772、0.762,Z=1.11、0.27,P=0.27、0.78)。结论 基于增强CT影像组学模型术前预测胃腺癌LNM效能较佳。  相似文献   

11.
It is remarkable that migraine is a prominent part of the phenotype of several genetic vasculopathies, including cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL), retinal vasculopathy with cerebral leukodystrophy (RVCL) and hereditary infantile hemiparessis, retinal arteriolar tortuosity and leukoencephalopahty (HIHRATL). The mechanisms by which these genetic vasculopathies give rise to migraine are still unclear. Common genetic susceptibility, increased susceptibility to cortical spreading depression (CSD) and vascular endothelial dysfunction are among the possible explanations. The relation between migraine and acquired vasculopathies such as ischaemic stroke and coronary heart disease has long been established, further supporting a role of the (cerebral) blood vessels in migraine. This review focuses on genetic and acquired vasculopathies associated with migraine. We speculate how genetic and acquired vascular mechanisms might be involved in migraine.  相似文献   

12.
Fibrinogen and fibrin structure and functions   总被引:12,自引:0,他引:12  
Fibrinogen molecules are comprised of two sets of disulfide-bridged Aalpha-, Bbeta-, and gamma-chains. Each molecule contains two outer D domains connected to a central E domain by a coiled-coil segment. Fibrin is formed after thrombin cleavage of fibrinopeptide A (FPA) from fibrinogen Aalpha-chains, thus initiating fibrin polymerization. Double-stranded fibrils form through end-to-middle domain (D:E) associations, and concomitant lateral fibril associations and branching create a clot network. Fibrin assembly facilitates intermolecular antiparallel C-terminal alignment of gamma-chain pairs, which are then covalently 'cross-linked' by factor XIII ('plasma protransglutaminase') or XIIIa to form 'gamma-dimers'. In addition to its primary role of providing scaffolding for the intravascular thrombus and also accounting for important clot viscoelastic properties, fibrin(ogen) participates in other biologic functions involving unique binding sites, some of which become exposed as a consequence of fibrin formation. This review provides details about fibrinogen and fibrin structure, and correlates this information with biological functions that include: (i) suppression of plasma factor XIII-mediated cross-linking activity in blood by binding the factor XIII A2B2 complex. (ii) Non-substrate thrombin binding to fibrin, termed antithrombin I (AT-I), which down-regulates thrombin generation in clotting blood. (iii) Tissue-type plasminogen activator (tPA)-stimulated plasminogen activation by fibrin that results from formation of a ternary tPA-plasminogen-fibrin complex. Binding of inhibitors such as alpha2-antiplasmin, plasminogen activator inhibitor-2, lipoprotein(a), or histidine-rich glycoprotein, impairs plasminogen activation. (iv) Enhanced interactions with the extracellular matrix by binding of fibronectin to fibrin(ogen). (v) Molecular and cellular interactions of fibrin beta15-42. This sequence binds to heparin and mediates platelet and endothelial cell spreading, fibroblast proliferation, and capillary tube formation. Interactions between beta15-42 and vascular endothelial (VE)-cadherin, an endothelial cell receptor, also promote capillary tube formation and angiogenesis. These activities are enhanced by binding of growth factors like fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor (VEGF), and cytokines like interleukin (IL)-1. (vi) Fibrinogen binding to the platelet alpha(IIb)beta3 receptor, which is important for incorporating platelets into a developing thrombus. (vii) Leukocyte binding to fibrin(ogen) via integrin alpha(M)beta2 (Mac-1), which is a high affinity receptor on stimulated monocytes and neutrophils.  相似文献   

13.
本文详细介绍了创伤后血糖应激适度理论,以及高血糖与感染和多器官功能不全综合征的关系;提出涉及胰岛B细胞功能不全的MODS实验诊断新方案和极化液个体化干预新措施,可早期发现创伤MODS、降低感染率及MODS发生率和病死率。  相似文献   

14.
目的:探讨腹膜后纤维化(RPF)导致肾积水的原因及诊治经验。方法:回顾分析2004年1月—2010年12月24例腹膜后纤维化致肾积水患者的诊治资料。结果:(1)RPF患者常见首发症状为腰背痛或腹痛(69.2%);(2)红细胞沉降率(ESR)增快和血清IgG4升高最常见。超声检查仅提示上尿路积水。RPF的静脉肾盂造影(IVP)和CT尿路成像(CTU)表现具有特征性。IVP肾盂输尿管显影不良时,CTU能较清晰的显示上尿路影像。CT扫描发现腹膜后软组织肿块9例(37.5%),优于超声检查;(3)输尿管松解和腹腔化手术治疗22例;行肾切除术1例;行输尿管置双J管术1例。最终确诊为继发性RPF8例,其中4例为术前诊断,3例为术中腹膜后软组织肿块冷冻活检证实,1例为术后病理证实;(4)特发性RPF手术后肾积水均获长期缓解,而继发性RPF的预后取决于原发疾病及其治疗方案。结论:影像学检查是诊断RPF的重要手段,CTU优于超声检查和IVP。输尿管松解和腹腔化手术可以使特发性RPF输尿管梗阻得到长期的缓解,术中对肿块进行冷冻活检有助于鉴别特发性和继发性RPF,及时调整治疗方案。  相似文献   

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Summary. Telemedicine and teleradiology hold the key for improving future health care delivery. In this paper we first review current communication and computer technologies used in telemedicine and teleradiology. Five examples in teleradiology applications are given including hospital-integrated picture archiving and communication systems, tele-neuro-imaging, telemammography, university consortium teleradiology service, and teleradiology for second opinion. Parameters important to teleradiology applications like costs, image quality, system reliability, and turn around time are considered. Data security is discussed, including patient confidentiality and image authenticity-which will be a major issue in future teleradiology applications.  相似文献   

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目的探讨儿童慢性顽固性咳嗽与肺炎支原体(MP)感染的关系及临床疗效观察。方法采用回顾性研究方法对于现将2005年3月至2008年3月在我院的55例确诊慢性顽固性咳嗽患儿,主要表现为肺炎支原体感染为临床特点进行分析,并进一步临床治疗研究。结果①临床特点:在55例确诊慢性咳嗽的患儿中,以慢性顽固性咳嗽为主要症状。58%(32/55)的病例无肺部体征;②外周血:85%(47/55)的病例外周血变化不大,WBC(4—10)×10 9/L之间,嗜酸性粒细胞增多;③特别检查:47.27%(26/55)肺炎支原体IgM(MP—IgM)抗体阳性,83.64%(46/55)PeR技术检测肺炎支原体特异性DNA;④X光报告为多种形式。结论肺炎支原体(MP)感染是引起儿童慢性顽固性咳嗽的病因之一,对儿童慢性咳嗽,特别是顽固性咳嗽的诊治中应更加重视。  相似文献   

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Abstract

Acetylcysteine has been utilized successfully in the treatment of acetaminophen overdose since the 1970s. Although prospective trials as to efficacy and safety of acetylcysteine were conducted, there were no randomized controlled trials. This commentary addresses the reasons for this, and the background to choice of dose of acetylcysteine utilized in the oral and IV dosing regimens. Nomograms to predict possible hepatotoxicity based upon time of ingestion of acetaminophen were developed from a relatively arbitrary definition of toxicity as an aspartate aminotransferase/alanine aminotransferase (ALT/AST) greater than 1000 IU/L. While these have proved generally useful, patients still continue to develop hepatic damage after acetaminophen overdose, particularly if they present late after ingestion. The optimum management of these patients remains unclear, and one area of uncertainty is the dose and duration of acetylcysteine in various circumstances. This article discusses the issues that need to be elucidated to better target changes in acetylcysteine dose. The potential for measurements of other markers to improve treatment selection is the subject of further research.  相似文献   

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Designing interprofessional primary care teams composed of physicians and nurse practitioners (NPs) is a national priority. We assessed how profession and gender affect teamwork and job satisfaction among primary care physicians and NPs by using survey data from 186 physicians and 398 NPs practicing in New York State. Our regression models show profession (NP vs physician) moderates the associations of gender with teamwork and job satisfaction. Among NPs, men had higher job satisfaction than women. Among physicians, women had higher job satisfaction than men. Our results can benefit interprofessional primary care teams to optimize their professional and gender mix.  相似文献   

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