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1.
目的:分析抗黑色素瘤分化相关基因5(MDA5)抗体阳性皮肌炎患者的肌肉FDG代谢、肿瘤发生率以及肺间质性改变在18F-FDG PET/CT的影像特征及其鉴别抗MDA5抗体阳性皮肌炎的价值。 方法:回顾性分析2016年6月至2019年7月在上海交通大学医学院附属仁济医院接受18F-FDG PET/CT检查的75例(34例抗MDA5抗体阳性,41例抗MDA5抗体阴性)皮肌炎患者[男21例、女54例,年龄(52.3±14.3)岁]和30名健康对照者[男10名、女20名,年龄(53.5±11.8)岁]的影像和临床资料,测定并计算肌肉SUV max及肌肉SUV max平均值(mSUV max);统计皮肌炎患者合并肿瘤性病变的情况;测定皮肌炎合并间质性肺炎患者肺炎病灶的SUV max。采用两独立样本 t检验、单因素方差分析、SNK检验和 χ2检验分析数据;行ROC曲线分析肌肉mSUV max鉴别抗MDA5抗体阳性皮肌炎的诊断效能。 结果:健康对照者、抗MDA5抗体阳性和抗MDA5抗体阴性皮肌炎患者的肌肉mSUV max分别为0.39±0.05、0.66±0.21和0.87±0.29( F=39.93, P<0.001);皮肌炎患者的肌肉mSUV max均高于健康对照者( q值:6.76、12.63,均 P<0.001);抗MDA5抗体阴性患者高于抗MDA5抗体阳性患者( q=5.79, P<0.001)。ROC AUC为0.74,当肌肉mSUV max取最佳阈值0.75时,在皮肌炎中鉴别出抗MDA5抗体阳性的准确性为74.7%(56/75)。抗MDA5抗体阴性患者中,恶性肿瘤6例(14.6%,6/41);抗MDA5抗体阳性患者中,无恶性肿瘤病例(0/34;χ2=5.41, P=0.020)。抗MDA5抗体阴性伴发间质性肺炎11例(26.8%, 11/41),抗MDA5抗体阳性伴发间质性肺炎33例(97.1%, 33/34;χ2=37.81, P<0.001);抗MDA5抗体阳性患者肺炎FDG代谢高于抗MDA5抗体阴性患者(SUV max:3.65±1.83和2.38±1.27;t=2.13, P=0.039)。 结论:抗MDA5抗体阳性皮肌炎患者的肌肉FDG代谢高于健康对照者,但低于抗MDA5抗体阴性患者。抗MDA5抗体阳性患者肿瘤性病变发生率低于抗MDA5抗体阴性患者。抗MDA5抗体阳性患者发生间质性肺炎的比例和严重程度均高于阴性患者。18F-FDG PET/CT对于鉴别抗MDA5抗体阳性皮肌炎具有一定价值。 相似文献
2.
《Nutrition, metabolism, and cardiovascular diseases : NMCD》2022,32(5):1227-1235
Background and aimsAlthough antithrombotic treatments are established for coronary artery disease (CAD), they increase the bleeding risk, especially in malnourished patients. The total thrombus-formation analysis system (T-TAS) is useful for the assessment of thrombogenicity in CAD patients. Here, we examined the relationships among malnutrition, thrombogenicity and 1-year bleeding events in patients undergoing percutaneous coronary intervention (PCI).Methods and resultsThis was a retrospective analysis of 300 consecutive CAD patients undergoing PCI. Blood samples obtained on the day of PCI were used in the T-TAS to compute the thrombus formation area under the curve. We assigned patients to two groups based on the geriatric nutritional risk index (GNRI): 102 patients to the lower GNRI group (≤98), 198 patients to the higher GNRI group (98<). The primary endpoint was the incidence of 1-year bleeding events defined by Bleeding Academic Research Consortium criteria types 2, 3, or 5. The T-TAS levels were lower in the lower GNRI group than in the higher GNRI group. Kaplan-Meier analysis showed worse 1-year bleeding event-free survival in the lower GNRI group compared with the higher GNRI group. The combined model of the GNRI and the Academic Research Consortium for High Bleeding Risk (ARC-HBR) had good calibration and discrimination for bleeding risk prediction. In addition, having a lower GNRI and ARC-HBR positivity was associated with 1-year bleeding events.ConclusionA lower GNRI could reflect low thrombogenicity evaluated by the T-TAS and determine bleeding risk in combination with ARC-HBR positivity. 相似文献
3.
基于F-FDG代谢显像的腹膜假黏液瘤PCI评分及肿瘤分级预测 《首都医科大学学报》2022,43(6):834-839
目的 本研究将探讨基于氟-18-脱氧葡萄糖(18F-fluorodeoxyglucose,18F-FDG)正电子发射型计算机断层显像/电子计算机断层显像(positron emission tomography/computed tomography,PET/CT) 的改良PET-腹膜癌指数(peritoneal cancer index,PCI)、最大标准化摄取值(maximum standardized uptake value,SUVmax)与最大标准化摄取值/肝脏平均标准化摄取值(SUVmax/ liver mean standardized uptake value, SUVmax/SUVmeanliver)预测腹膜假黏液瘤(pseudomyxoma peritonei,PMP)组织病理学分级的能力。 方法 回顾性分析2017年1月至2022年6月间31例阑尾来源PMP患者的临床病理学数据及34例次(3名患者行2次检查)18F-FDG PET/CT检查结果。将13个特定腹盆区域PMP病灶的SUVmax评分汇总得到PET-PCI。同时还测量了腹盆腔病灶的SUVmax与SUVmax/SUVmeanliver。 结果 低级别PMP患者14例、高级别PMP患者12例、高级别伴印戒细胞PMP患者5例。高级别PMP患者的PET-PCI、SUVmax和SUVmax/SUVmeanliver值均高于低级别PMP患者(PET-PCI: 23.08±7.47 vs 15.81±10.59,P=0.047; SUVmax:7.91±4.67 vs 6.73±3.99,P=0.470;SUVmax/SUVmeanliver:3.63±1.89 vs 3.17±2.70,P=0.614)。高级别伴印戒细胞PMP患者的 PET-PCI、SUVmax及SUVmax/SUVmeanliver值均高于高级别PMP患者(PET-PCI:25.20±8.84 vs 23.08±7.47,P=0.614; SUVmax:9.29±8.46 vs 7.91±4.67,P=0.660;SUVmax/SUVmeanliver:3.73±1.83 vs 3.63±1.89,P=0.917)。PET-PCI、SUVmax及SUVmax/SUVmeanliver值的高低与PMP分级一致,但只有高级别PMP患者的PET-PCI与低级别PMP患者之间的差异有统计学意义。 结论 与SUVmax及SUVmax/SUVmeanliver相比,PET-PCI能更好地反映PMP患者的组织病理学分级。 相似文献
4.
Evaluation of the ossification of the medial clavicular epiphysis plays a key role in forensic age estimation. The purpose of the present study was to assess a new numerical cut-off at the age of 18 years, taking into consideration Magnetic Resonance (MR) images of the medial clavicular epiphysis. We analyzed 163 MR scans of Italian subjects aged between 14 and 25 years. Using the data obtained we calculated two ratios: REM-1 (ratio between the length of the whole epiphysis and the length of the metaphysis) and REM-2 (ratio between the length of epiphyseal-metaphyseal fusion and the length of the metaphysis). In 68 out of 163 cases it was not possible to measure REM-2. The reproducibility was demonstrated using the Intraclass Correlation Coefficient (ICC) (Cronbach’s alpha > 0.80). REM-1 and REM-2 were compared in each category of age (adult and minor) by the Wilcoxon signed-rank test. The cut-off points for measurements of REM-1 and REM-2 were determined by logistic regression. For REM-1, the cut-off scores were 0.83 for all individuals (accuracy = 94.77%) and males (accuracy = 96.05%), and 0.86 for females (accuracy = 92.30%). For REM-2, the cut-off values were 0.40 for all individuals and males (accuracy = 100.00%), and 0.41 for females (accuracy = 100.00%). Finally, receiver operating characteristic (ROC) curves for age classification based on REM-1 and REM-2 were constructed, showing that REM-2 had the highest discriminative power. Thus, a new cut-off model for predicting the age of majority has been introduced, conducting a quantitative analysis thanks to the use of a high-resolution imaging tool. 相似文献
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Brian Miller MD Rama Vunnam MD Olurotimi Mesubi MD Mark F. Smith PhD Wengen Chen MD Jagat Bandhu Mahat MD Soren M. Bentzen D.M.Sc PhD Vincent See MD Alejandro Restrepo MD Stephen Shorofsky MD PhD Vasken Dilsizian MD Timm-Michael L. Dickfeld MD PhD 《Journal of cardiovascular electrophysiology》2021,32(8):2238-2245
8.
《Clinical neurophysiology》2021,132(10):2357-2364
ObjectivesTo investigate the subcortical somatosensory evoked potentials (SEPs) to electrical stimulation of either muscle or cutaneous afferents.MethodsSEPs were recorded in 6 patients suffering from Parkinson’s disease (PD) who underwent electrode implantation in the pedunculopontine (PPTg) nucleus area. We compared SEPs recorded from the scalp and from the intracranial electrode contacts to electrical stimuli applied to: 1) median nerve at the wrist, 2) abductor pollicis brevis motor point, and 3) distal phalanx of the thumb. Also the high-frequency oscillations (HFOs) were analysed.ResultsAfter median nerve and pure cutaneous (distant phalanx of the thumb) stimulation, a P1-N1 complex was recorded by the intracranial lead, while the scalp electrodes recorded the short-latency far-field responses (P14 and N18). On the contrary, motor point stimulation did not evoke any low-frequency component in the PPTg traces, nor the N18 potential on the scalp. HFOs were recorded to stimulation of all modalities by the PPTg electrode contacts.ConclusionsStimulus processing within the cuneate nucleus depends on modality, since only the cutaneous input activates the complex intranuclear network possibly generating the scalp N18 potential.SignificanceOur results shed light on the subcortical processing of the somatosensory input of different modalities. 相似文献
9.
目的分析广东汉族人群D18S51基因座等位基因的特殊分型现象。方法采用Chelex-100法提取DNA,采用Powerplex■21体系对广东汉族9 419例研究对象进行PCR复合扩增,采用毛细管电泳分析STR基因座的等位基因分型,采用IdentifilerTM体系验证其特殊分型。结果发现D18S51基因座存在三带型等位基因和off-ladder(OL)等位基因2种特殊分型,基因型频率分别为0.010 6%和0.021 2%。OL等位基因命名为28,由母亲遗传给孩子。不同检测体系证实了特殊分型发生的真实性。结论对于STR基因座的特殊分型,应采用不同试剂盒验证,正确命名OL等位基因及计算三带型等位基因的亲权指数。 相似文献
10.
目的探讨18F-FDG PET/CT对乳腺癌术后患者复发及转移诊断、治疗中的临床价值。方法收集并回顾性分析行18F-FDG PET/CT检查的94例女性乳腺癌术后患者,病理类型均为浸润性导管癌,年龄为28~79岁。患者均进行18F-FDG PET/CT全身显像,检测结果均应用半定量分析法和目测法判断。分析18F-FDG PET/CT对真阳性患者临床治疗策略的影响。结果18F-FDG PET/CT诊断乳腺癌术后复发转移的灵敏度、特异性、准确度、阳性预测值和阴性预测值分别为96.92%、89.65%、94.68%、91.30%、92.85%。依据18F-FDG PET/CT结果,58.51%真阳性患者最终更改了治疗方案。结论18F-FDG PET/CT能够有效评估乳腺癌术后复发及转移病例并且指导乳腺癌患者的临床治疗。 相似文献