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Neurological abnormalities identified via neuroimaging are common in patients with Alzheimer's disease. However, it is not yet possible to easily detect these abnormalities using head computed tomography in the early stages of the disease. In this review, we evaluated the ways in which modern imaging techniques such as positron emission computed tomography, single photon emission tomography, magnetic resonance spectrum imaging, structural magnetic resonance imaging, magnetic resonance diffusion tensor imaging, magnetic resonance perfusion weighted imaging, magnetic resonance sensitive weighted imaging, and functional magnetic resonance imaging have revealed specific changes not only in brain structure, but also in brain function in Alzheimer's disease patients. The reviewed literature indicated that decreased fluorodeoxyglucose metabolism in the temporal and parietal lobes of Alzheimer's disease patients is frequently observed via positron emission computed tomography. Furthermore, patients with Alzheimer's disease often show a decreased N-acetylaspartic acid/creatine ratio and an increased myoinositol/creatine ratio revealed via magnetic resonance imaging. Atrophy of the entorhinal cortex, hippocampus, and posterior cingulate gyrus can be detected early using structural magnetic resonance imaging. Magnetic resonance sensitive weighted imaging can show small bleeds and abnormal iron metabolism. Task-related functional magnetic resonance imaging can display brain function activity through cerebral blood oxygenation. Resting functional magnetic resonance imaging can display the functional connection between brain neural networks. These are helpful for the differential diagnosis and experimental study of Alzheimer's disease, and are valuable for exploring the pathogenesis of Alzheimer's disease. 相似文献
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目的 观察18F-FDG PET/CT影像组学判断乳腺癌人表皮生长因子受体2(HER2)表达状态的价值。方法 纳入100例乳腺癌患者,包括HER2(+)组28例、HER2(-)组72例,比较组间PET/CT参数,包括病灶最大标准摄取值(SUVmax)及其标准差(SD)、平均标准摄取值(SUVmean)及肿瘤代谢体积的差异。于标准化后的PET图像中手动分割病灶ROI,获取其影像组学特征,根据降维后的影像组学特征及其系数的线性加权获得病灶影像组学风险评分(RRS);针对差异有统计学意义的指标绘制受试者工作特征曲线,计算曲线下面积(AUC),评价其判断乳腺癌患者HER2状态的效能。采用Bootstrap 1000重复抽样进行内部验证,计算校正AUC,并以DeLong检验比较。以决策曲线分析评价患者净获益情况。结果 HER2(+)组病灶SUVmax、SUVmean及SD均大于HER2(-)组(P均<0.05)。共获取704个影像组学特征,经筛选最终获得10个非零系数的特征用于计算RRS,HER2(+)组RRS大于HER2(-)组(P<0.001)。以RRS判断乳腺癌患者HER2状态的AUC大于病灶SUVmax、SUVmean及SD (P均<0.05),其诊断敏感度为78.57%、特异度为77.78%。决策曲线分析结果表明,RRS可在较大概率阈值范围内带给患者更多净获益。结论 18F-FDG PET/CT影像组学用于判断乳腺癌HER2状态具有一定价值。 相似文献
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骨与软组织肉瘤发病率相对较低,但多数恶性程度高,预后差,早期诊断是改善预后的关键。~(18)F-FDG PET/CT可用于骨与软组织肉瘤的诊断及鉴别诊断、肿瘤分级、确定活检部位、检测复发及转移、评价疗效及预后等各方面。本文就~(18)F-FDG PET/CT在骨与软组织肉瘤中的应用进展进行综述。 相似文献
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Atherosclerosis has long been known as an inflammatory disease. However, whether targeting inflammation improves outcomes was unproven until the recent results of CANTOS (Canakinumab Anti-Inflammatory Thrombosis Outcomes Study). In this review, we reflect on why it has taken a long time to prove the inflammatory hypothesis of atherosclerosis and derive important lessons for the future. In particular, we discuss the off-target immune-modulatory effects of approved cardiovascular therapies, review the attempted anti-inflammatory therapies including the recently published CIRT (Cardiovascular Inflammation Reduction Trial), and discuss the likely reasons for their failures. We further build on CANTOS to review the immune-modulatory therapies for atherosclerosis currently in trials, and discuss the likelihood of their added value as well as the potential hazard associated with their use. We finally argue for a critical approach to the use of animal models, coupled with the use of humans as model organisms to accelerate the identification of the most appropriate targets. 相似文献
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Prognostic value of pretreatment 18F‐fluorodeoxyglucose positron emission tomography/CT volume‐based parameters in patients with oropharyngeal squamous cell carcinoma with known p16 and p53 status 下载免费PDF全文
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目的 观察18F-AlF-NOTA-octreotide(18F-OCT)联合18F-FDG PET/CT显像用于神经内分泌瘤(NET)的临床价值。方法 回顾性分析21例同期接受18F-OCT和18F-FDG PET/CT显像并经病理学证实的NET患者,其中7例已接受原发瘤根治性切除术、2例原发灶不明;根据2010年WHO分级标准,将12例明确存在原发瘤者分为中/低级别组9例和高级别组3例,对比原发瘤及转移灶在2种显像中的阳性比例、摄取水平及治疗后影像学变化。结果 原发瘤大小与18F-FDG最大标准摄取值(SUVmax)显著相关(r=0.731,P<0.05),但与18F-OCT无明显相关(r=0.311,P>0.05)。中/低级别组9例原发瘤中,8例18F-OCT显像阳性,SUVmax中位数为33.80(6.10,56.55);7例18F-FDG显像阳性,SUVmax中位数3.80(1.40,8.80)(Z=-2.345,P<0.05)。高级别组3例原发瘤中,18F-FDG检出3例,18F-OCT 2例。18F-OCT联合18F-FDG PET/CT显像检测转移灶阳性比例高于单一。追踪观察1例胰腺NET术后肝脏多发转移患者,奥曲肽对其18F-OCT显像阳性病灶取得良好疗效。结论 18F-OCT联合18F-FDG PET/CT显像可作为检测NET的辅助手段,并有望用于预估疗效。 相似文献