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《Clinical gastroenterology and hepatology》2022,20(5):1112-1121.e4
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Optic nerve injury demonstrated by MRI with STIR sequences 总被引:1,自引:0,他引:1
S. Takehara T. Tanaka K. Uemura Y. Shinohara T. Yamamoto T. Tokuyama A. Satoh 《Neuroradiology》1994,36(7):512-514
We studied nine patients with optic nerve injury associated with closed head trauma by magnetic resonance imaging (MRI) with short inversion time inversion recovery (STIR) sequences on 11 occasions from 4 days to 14 years after the injury: three studies were within 17 days and eight over 4 months to 14 years. MRI revealed abnormal high signal in 10 of the 11 injured nerves. MRI 4 days after the injury showed no abnormality. 相似文献
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Magnetization prepared segmented acquisition requires a view order that maximizes signal contrast during the acquisition of the central portion of k-space. Steady state free precession (SSFP) acquisition further requires a view order that minimizes changes in phase-encoding gradients from one repetition to the next in order to minimize eddy current artifacts. In this article, optimal view ordering schemes satisfying these two requirements are formulated and applied to inversion prepared 3D SSFP contrast-enhanced MR angiography (MRA). Experiments on phantoms and pigs demonstrated improved background suppression and reduced image artifacts. 相似文献
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FLAIR序列脑室内脑脊液搏动伪影(VCSFA)的表现及初步分析 总被引:1,自引:0,他引:1
目的探讨FLAIR序列脑室内脑脊液搏动伪影的表现及其与年龄、性别、脑室大小的关系。方法对100例正常成人行头颅MR检查,并对FLAIR序列脑室内脑脊液搏动伪影(VCSFA)进行观察统计分析。结果VCSFA表现为脑室内轻微或明显高信号,在Ⅲ,Ⅳ脑室最常见,在不同年龄组存在明显差异(P<0.05),VCSFA组Ⅲ,Ⅳ脑室左右径大于无VCSFA组(P<0.05)。结论VCSFA是由反转延迟造成的,随着年龄增长及脑室增大,VCSFA出现频率增加,与性别无关。 相似文献
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The detection of a change in a face stimulus was studied in an oddball paradigm. Event-related potentials (ERPs) and MEG responses to face stimuli were recorded in four conditions: 1) happy standard, neutral deviant; 2) neutral standard, neutral deviant; 3) inverted happy standard, inverted neutral deviant; 4) inverted neutral standard, inverted neutral deviant. In all conditions, the target was a face with glasses. Neutral deviants elicited a negative deflection (with a maximum around 280 ms) in ERP and MEG responses, an effect similar to auditory mismatch negativity. Face inversion diminished deviance-related negativity, implying an important role of face recognition in the observed effect. Emotional content and larger physical differences between stimuli in conditions 1 and 3 compared to conditions 2 and 4 did not show statistically significant effect on the neutral-deviant-related negativity. 相似文献
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《The Knee》2022
BackgroundKnee osteoarthritis (KOA) is increasingly prevalent in North American society. The significant societal burden it represents makes it essential to promote and target new treatments in earlier phases of the disease. Among others, subchondroplasty is a newly documented technique using calcium phosphate injection targeting the osteochondral lesions preceding KOA, also known as Bone Marrow Lesions (BMLs). This article aimed to review the existing literature on clinical and radiological outcomes of subchondroplasty in the treatment of BMLs in KOA.MethodA systematic review was performed using PubMed, Embase, Medline and Cochrane Database of Systematic Reviews. Studies on calcium phosphate injections into BMLs for KOA and its clinical and radiological outcomes were screened and reviewed by independent evaluators.ResultsAfter screening, ten articles were included, totaling 540 patients. Follow-up ranged from 6 months to 7 years. Overall, the procedure showed significant functional and quality of life improvement, as well as pain relief, as shown by Patients-Reported Outcomes Measures (PROMs). There were very few complications reported, the most important being leakage of calcium phosphate outside the targeted site. Conversion rate to total knee arthroplasty (TKA) ranged from 14 % to 30 % at 2 years post-procedure. Long term radiological outcomes have been poorly documented.ConclusionsSubchondroplasty is a promising avenue for the treatment of KOA. However, quality evidence is still required before any real conclusions and practical management guidelines can be drawn. Prospective, randomized studies with a control group and a rigorous assessment of long-term clinical and radiological outcomes are recommended. 相似文献
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26例9号染色体臂间倒位的表型效应的探讨 总被引:1,自引:0,他引:1
目的探讨9号染色体臂间倒住的临床及遗传效应。方法通过对外周血淋巴细胞培养,制备染色体。G显带染色体分析。结果2317例病人中检出26例9号染色体臂间倒位(1.12%),其中有15例患者(占58%)伴有流产、不育、不孕、胎儿畸形等临床表现,2例合并有染色体数目异常。结论9号染色体臂间倒位具有一定遗传效应不应忽视。 相似文献
10.
Miguel Urioste María Luisa Martínez-Frías Eva Bermejo Nicols Jimnez Dolores Romero Carmen Nieto Amelia Villa 《American journal of medical genetics. Part A》1994,49(1):94-97
We report on a newborn infant with clinical and radiological manifestations of some type of short rib-polydactyly syndrome who died soon after birth. Chromosomal studies on peripheral blood lymphocytes and chondrocytes demonstrated an apparently balanced pericentric inversion of chromosome 4 (present in the mother also). This association may have occurred by chance but, if not, the chromosomal breakpoints could interrupt the gene responsible for short rib-polydactyly syndromes, or else be related to the mechanism of short rib-polydactyly syndromes. © 1994 Wiley-Liss, Inc. 相似文献