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541.
目的使用独立分量分析方法探索督脉穴位经皮电刺激对脑功能的影响。方法使用1.5T GE Signa Excite核磁成像仪对一位女性脑外伤患者进行BOLD成像。采用组块设计,静息期与刺激期交替,组块长度均为30 s。数据处理采用GIFT、SPM5和MRIcro软件进行,并将独立分量分析与SPM软件处理的结果进行比较。结果采用GIFT中的扩展Infomax算法进行独立分量分析,显示有13个独立成分,每一独立成分包含一空间图和相应的时间变化曲线。任务相关性独立成分的空间激活图与SPM5的分析结果类似,但并不完全相同。此外,这些任务相关性独立成分的时间曲线与SPM所用的经典血流动力相应函数模型的形状并不一致。结论在使用模型依赖的数据分析方法如SPM之前,可以使用独立分量分析探索fMRI数据并获得先验知识。 相似文献
542.
首先采用相关分析初步检测可能的功能激活区域,并以初步检测的功能激活区域作为空间约束条件,对fMRI数据进行时间模式的独立成分分析,然后利用功能实验设计时序信息,通过典型相关分析方法对独立成分排序,自动识别与功能实验设计相关的功能信号成分,最后以识别的功能信号成分作为参考函数,重新利用相关分析自适应地分析fMRI数据。通过对实际的fMRI数据分析验证了提出方法的有效性及可靠性。 相似文献
543.
Spontaneous regression of two supraophthalmic internal cerebral artery aneurysms following flow pattern alteration 总被引:2,自引:0,他引:2
We report on a patient with fibromuscular dysplasia who presented with a right-sided giant calcified cavernous internal carotid artery (ICA) aneurysm and two additional supraophthalmic ICA aneurysms. Endovascular closure of the right ICA using detachable balloons was performed with collateralisation of the right hemisphere via the right-sided posterior communicating and the anterior communicating arteries. Repeat angiography after 6 months demonstrated spontaneous complete regression of the two supraophthalmic aneurysms, although the parent vessel was still perfused. In comparison to the former angiography, the flow within the parent vessel was reversed due to the proximal ICA balloon occlusion. MRI demonstrated that the aneurysms were not obliterated by thrombosis alone, but showed a real regression in size. This case report demonstrates that changes in cerebral hemodynamics potentially lead to plastic changes in the vessel architecture in adults and that aneurysms can be flow-related, even if not associated with high flow fistulas or arteriovenous malformations, especially in cases with an arterial wall disease. 相似文献
544.
545.
Wijnand J. Stuijfzand Stefan P. Schumacher Roel S. Driessen Adriaan A. Lammertsma Amber L. Bakker Mischa T. Rijnierse Albert C. van Rossum Peter M. van de Ven Alexander Nap Yolande Appelman Niels van Royen Maarten A. van Leeuwen Jorrit S. Lemkes Pieter G. Raijmakers Paul Knaapen 《JACC: Cardiovascular Interventions》2019,12(10):967-979
ObjectivesThe randomized clinical VANISH (Impact of Vascular Reparative Therapy on Vasomotor Function and Myocardial Perfusion: A Randomized [15O]H2O PET/CT Study) trial was conducted to assess quantitative myocardial blood flow (MBF) during resting, hyperemia, and cold pressor testing (CPT) with positron emission tomographic perfusion imaging after the implantation of a bioresorbable everolimus-eluting scaffold compared with a drug-eluting stent.BackgroundLong-term resorption of the bioresorbable everolimus-eluting scaffold reinstates normal vessel geometry, allowing natural regeneration of the newly formed endothelium with revival of vasomotor function.MethodsSixty patients (18 to 65 years of age) with single-vessel disease and type A or B1 lesions were randomized in a 1-to-1 fashion. Approximately 1 month, 1 year, and 3 years after device implantation, patients underwent [15O]H2O cardiac positron emission tomography. The primary endpoint was the interaction of device type and evolution over time of hyperemic MBF, coronary flow reserve, or CPT reserve. At 3-year follow-up, control invasive coronary angiography with optical coherence tomography was performed.ResultsFifty-nine (98%), 56 (93%), and 51 (85%) patients successfully completed 1-month, 1-year, and 3-year follow-up positron emission tomography, respectively, and no culprit vessel events were registered during follow-up time. The primary study endpoint (i.e., interaction between device type and time) was nonsignificant for hyperemic MBF, CPT reserve, and coronary flow reserve (p > 0.05 for all). In all patients, hyperemic MBF decreased from 1 to 3 years (p = 0.02), while coronary flow reserve was lower at 3-year follow-up compared with 1-month and 1-year follow-up (p = 0.03 for both). After 3 years, percentage area stenosis measured with optical coherence tomography was higher within the bioresorbable everolimus-eluting scaffold compared with the drug-eluting stent (p = 0.03).ConclusionsThe hypothesized beneficial effects of scaffold resorption did not translate to improved MBF during maximal hyperemia or endothelium-dependent vasodilation by CPT. 相似文献
546.
547.
Zeinab Vahidinia Abolfazl Azami Tameh Majid Nejati Cordian Beyer Sayyed Alireza Talaei Sepideh Etehadi Moghadam Mohammad Ali Atlasi 《Pathology, research and practice》2019,215(9):152519
Ischemic stroke is the main cause of disability and mortality worldwide. Apoptosis and inflammation have an important role in ischemic brain injury. Mesenchymal stem cells (MSCs) have protective effects on stroke treatment due to anti-inflammatory properties. The inhibition of the C-Jun N-terminal kinase (JNK) pathway may be one of the molecular mechanisms of the neuroprotective effect of MSCs in ischemic brain injury.Twenty-eight male Wistar rats were divided randomly into 3 groups. Except the sham group, others subjected to transient middle cerebral artery occlusion (tMCAO). Bone marrow MSCs or saline were injected 3 h after tMCAO. Sensorimotor behavioral tests were performed 24 and 72 h after ischemia and reperfusion (I/R). The rats were sacrificed 72 h after I/R and infarct volume was measured by TTC staining. The number of apoptotic neurons and astrocytes in the peri-infarct area was assessed by TUNEL assay. The morphology of cells was checked by Nissl staining, and the expression of p-JNK was detected by immunohistochemistry and Western blot.Behavioral scores were improved and infarct volume was reduced by MSCs 24 h and 72 h after tMCAO. TUNEL assay showed that neuronal apoptosis and astroglial activity in the penumbra region were reduced by MSCs. Also, Nissl staining showed lower neuronal apoptosis in BMSCs-treated rats compared to controls. JNK phosphorylation which was profoundly induced by ischemia was significantly decreased after MSCs treatment.We concluded that anti-apoptotic and anti-inflammatory effects of MSCs therapy after brain ischemia may be associated with the down-regulation of p-JNK. 相似文献
548.
Dezhao Kong Zhengjun Xie Liqiang Liu Shanshan Song Hua Kuang Gang Cui 《Food and Agricultural Immunology》2017,28(2):260-273
Sensitive and specific anti-sterigmatocystin (STG) monoclonal antibody (mAb) 4G10 was obtained by immunization and cell fusion. An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) method and lateral-flow immunochromatographic assay (ICA) strip method were developed for the detection of STG in cereal products based on this mAb. The 50% inhibition concentration and limit of detection for the ic-ELISA method were 0.092 and 0.015?ng/mL, respectively. The visual limit of detection (vLOD) and cut-off value for the lateral-flow ICA strip method were 0.1 and 0.5?ng/mL, respectively. From the analysis of different cereal samples (wheat, maize and rice), the recovery rates ranged from 78.3% to 122.0% for the ic-ELISA method. For the lateral-flow ICA strip, the vLODs were 3, 1.2 and 3?ng/g, and the cut-off values were 12, 6 and 6?ng/g for wheat, maize and rice, respectively. Therefore, both of the developed methods are suitable for the on-site detection and rapid screening of numerous samples. 相似文献
549.
J.C. Klein M. Rolinski L. Griffanti K. Szewczyk‐Krolikowski F. Baig C. Ruffmann A.R. Groves R.A.L. Menke M.T. Hu C. Mackay 《NMR in biomedicine》2018,31(4)
Magnetic resonance imaging (MRI) studies in early Parkinson's disease (PD) have shown promise in the detection of disease‐related brain changes in the white and deep grey matter. We set out to establish whether intrinsic cortical involvement in early PD can be detected with quantitative MRI. We collected a rich, multi‐modal dataset, including diffusion MRI, T1 relaxometry and cortical morphometry, in 20 patients with early PD (disease duration, 1.9 ± 0.97 years, Hoehn & Yahr 1–2) and in 19 matched controls. The cortex was reconstructed using FreeSurfer. Data analysis employed linked independent component analysis (ICA), a novel data‐driven technique that allows for data fusion and extraction of multi‐modal components before further analysis. For comparison, we performed standard uni‐modal analysis with a general linear model (GLM). Linked ICA detected multi‐modal cortical changes in early PD (p = 0.015). These comprised fractional anisotropy reduction in dorsolateral prefrontal, cingulate and premotor cortex and the superior parietal lobule, mean diffusivity increase in the mesolimbic, somatosensory and superior parietal cortex, sparse diffusivity decrease in lateral parietal and right prefrontal cortex, and sparse changes to the cortex area. In PD, the amount of cortical dysintegrity correlated with diminished cognitive performance. Importantly, uni‐modal analysis detected no significant group difference on any imaging modality. We detected microstructural cortical pathology in early PD using a data‐driven, multi‐modal approach. This pathology is correlated with diminished cognitive performance. Our results indicate that early degenerative processes leave an MRI signature in the cortex of patients with early PD. The cortical imaging findings are behaviourally meaningful and provide a link between cognitive status and microstructural cortical pathology in patients with early PD. 相似文献
550.
目的 以负荷核素心肌灌注显像(single photon emission computedtomography/myocardial perfusion imaging,SPECT/MPI)为标准,探讨基于工作站的CT-冠状动脉血流储备分数(CT-fractional flow reserve,CT-FFR)对于诊断... 相似文献