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991.
Significance of longitudinal changes in the default‐mode network for cognitive recovery after stroke
Ji‐Young Park Yun‐Hee Kim Won Hyuk Chang Chang‐hyun Park Yong‐Il Shin Sung Tae Kim Alvaro Pascual‐Leone 《The European journal of neuroscience》2014,40(4):2715-2722
Although a considerable number of patients suffer from cognitive impairments after stroke, the neural mechanism of cognitive recovery has not yet been clarified. Repeated resting‐state functional magnetic resonance imaging (fMRI) was used in this study to examine longitudinal changes in the default‐mode network (DMN) during the 6 months after stroke, and to investigate the relationship between DMN changes and cognitive recovery. Out of 24 initially recruited right‐hemispheric stroke patients, 11 (eight males, mean age 55.7 years) successfully completed the repeated fMRI protocol. Patients underwent three fMRI sessions at 1, 3 and 6 months after stroke. Their DMNs were analysed and compared with those of 11 age‐matched healthy subjects (nine males, mean age 56.2 years). Correlations between DMN connectivity and improvement of the cognitive performance scores were also assessed. The stroke patients were found to demonstrate markedly decreased DMN connectivity of the posterior cingulate cortex, precuneus, medial frontal gyrus and inferior parietal lobes at 1 month after stroke. At 3 months after stroke, the DMN connectivity of these brain areas was almost restored, suggesting that the period is critical for neural reorganization. The DMN connectivity of the dorsolateral prefrontal cortex in the contralesional hemisphere showed a significant correlation with cognitive function recovery in stroke patients, and should be considered a compensatory process for overcoming cognitive impairment due to brain lesion. This is the first longitudinal study to demonstrate the changes in DMN during recovery after stroke and the key regions influencing cognitive recovery. 相似文献
992.
Central cord pain is very difficult to relieve, even with the many kinds of medical and surgical treatments available. Following spinal cord infarctions, central cord pain can develop. The problems that may arise could include limb pain, pelvic pain, difficulties voiding, and difficulties defecating. We are reporting a case of central cord pain caused by a spinal cord infarction of the conus medullaris. Limb pain was reduced by spinal cord stimulation. Voiding and defecation difficulties and pelvic pain were reduced by sacral nerve stimulation. Thus, in a case involving both intractable limb and pelvic pain, a combination therapy of these two stimulations might be an effective treatment modality. 相似文献
993.
994.
Sung Jin Kwon Jeongsook Park So Yun Park Kwang Seop Song Sun Tae Jung So Bong Jung Ik Ryeul Park Wan Sung Choi Sun Ok Kwon 《中国神经再生研究》2013,8(10):922-929
The hippocampus is a brain region responsible for learning and memory functions. The purpose of this study was to investigate the effects of low-intensity exercise and bright light exposure on neurogenesis and brain-derived neurotrophic factor expression in adult rat hippocampus. Male Sprague-Dawley rats were randomly assigned to control, exercise, light, or exercise + light groups (n = 9 per group). The rats in the exercise group were subjected to treadmill exercise (5 days per week, 30 minutes per day, over a 4-week period), the light group rats were irradiated (5 days per week, 30 minutes per day, 10 000 lx, over a 4-week period), the exercise + light group rats were subjected to treadmill exercise in combination with bright light exposure, and the control group rats remained sedentary over a 4-week period. Compared with the control group, there was a significant increase in neurogenesis in the hippocampal dentate gyrus of rats in the exercise, light, and exercise + light groups. Moreover, the expression level of brain-derived neurotrophic factor in the rat hippocampal dentate gyrus was significantly higher in the exercise group and light group than that in the control group. Interestingly, there was no significant difference in brain-derived neurotrophic factor expression between the control group and exercise + light group. These results indicate that low-intensity treadmill exercise (first 5 minutes at a speed of 2 m/min, second 5 minutes at a speed of 5 m/min, and the last 20 minutes at a speed of 8 m/min) or bright-light exposure therapy induces positive biochemical changes in the brain. In view of these findings, we propose that moderate exercise or exposure to sunlight during childhood can be beneficial for neural development. 相似文献
995.
996.
Du Hwan Kim Mathieu Boudier-Revret Duk Hyun Sung Min Cheol Chang 《The journal of spinal cord medicine》2022,45(2):316
Context: Deep vein thrombosis (DVT), a frequent complication of spinal cord injury, is occasionally caused by neurogenic heterotopic ossification (NHO). In most cases of NHO, the hip joint is affected. Herein, we present a case of paraplegia following radiation-induced myelopathy that presented with left leg swelling due to DVT in the common iliac vein (CIV) caused by venous compression by NHO on the anterior lower lumbar spine.Findings: A 28-year-old man with complete paraplegia due to radiation-induced myelopathy presented with left lower extremity swelling 6 years after the onset of paraplegia. DVT in the left CIV was observed on computed tomography venography. The left CIV was significantly compressed between the NHO at the anterior longitudinal ligament of the lumbar spine and the right common iliac artery, suggestive of May-Thurner syndrome. Slightly distal to that compressed area, the left CIV was significantly compressed by the large NHO at the anterior longitudinal ligament of the lumbar spine.Conclusions: We believe that such compression of the left CIV would have contributed to the development of DVT. This case shows that DVT might be caused by NHO at the anterior aspect of the lumbar vertebral body, and this may help clinicians identify the main cause of DVT in the leg. 相似文献
997.
运动性心律失常是指发生于机体剧烈运动期间或之后的心律失常。临床表现不一,从心悸、头晕、晕厥、心绞痛、急性心肌梗死和充血性心力衰竭,甚至到心脏性猝死。运动性心律失常可见于心肌缺血,如患有动脉粥样硬化性心脏病以及患有原发性或继发性心肌病的患者。然而,也可能发生在似乎健康的个体。在后一组人群中,运动性心律失常可以是良性的,但也可以是获得性(如药物诱发)或先天性(如先天性长QT综合征或致心律失常性右室发育不良)心电活动或结构的异常而呈恶性。这种潜在病理生理学机制的复杂性,使运动性心律失常的诊断和治疗成为临床医学上的… 相似文献
998.
Yoo Duk Choi Sung‐Hoon Jung Ho‐Young Yhim Jae‐Yong Kwak Ho Sung Park Myung‐Geun Shin Yeo‐Kyeoung Kim Hyeoung‐Joon Kim Je‐Jung Lee 《American journal of hematology》2013,88(9):774-779
Several studies have suggested the possibility of a prognostic relationship between Epstein–Barr virus (EBV) and diffuse large B‐cell lymphoma (DLBCL). The clinical outcome of EBV‐associated DLBCL is not clear, especially since the introduction of rituximab. We retrospectively analyzed 222 elderly patients (≥50 years) with DLBCL who received R‐CHOP chemotherapy and evaluated the state of EBV‐encoded RNA‐1 (EBER). Eighteen cases (8.1%) were EBER‐positive (+). After a median of six cycles of R‐CHOP chemotherapy, the response rate (≥partial response) was 72.2% (13/18) in the EBV (+) patients and 90.2% (184/204) in the EBV (?) DLBCL patients (P = 0.021). Four of 18 (22.2%) EBV (+) DLBCL patients received two or fewer cycles of R‐CHOP chemotherapy. R‐CHOP chemotherapy was also interrupted early more frequently compared with the EBV (?) group (2.5%) (P = 0.00). At a median follow‐up of 32.8 months, there was no significant difference in the overall survival between the groups (P = 0.627). The EBV (+) DLBCL patients with early interruption of R‐CHOP chemotherapy showed a trend toward a high EBV‐DNA titer (≥1,000 copies/mL) (P = 0.091). The results suggest that the EBV (+) tumoral status of elderly DLBCL patients who undergo R‐CHOP chemotherapy does not predict their survival but that their EBV status may contribute to the early interruption of R‐CHOP chemotherapy. Am. J. Hematol. 88:774–779, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
999.
Vascular remodeling at both branch ostia in bifurcation disease assessed by intravascular ultrasound
1000.
Seong-Joon Koh Jong Pil Im Ji Won Kim Byeong Gwan Kim Kook Lae Lee Sang Gyun Kim Joo Sung Kim Hyun Chae Jung 《World journal of gastroenterology : WJG》2013,19(10):1632-1638
AIM:To investigate long-term outcome in obscure gastrointestinal bleeding(OGIB) after negative capsule endoscopy(CE) and identify risk factors for rebleeding.METHODS:A total of 113 consecutive patients underwent CE for OGIB from May 2003 to June 2010 at Seoul National University Hospital.Ninety-five patients(84.1%) with a subsequent follow-up after CE of at least 6 mo were enrolled in this study.Follow-up data were obtained from the patients’ medical records.The CE images were reviewed by two board-certified gastroenterologists and consensus diagnosis was used in all cases.The primary outcome measure was the detection of rebleeding after CE,and factors associated with rebleeding were evaluated using multivariate analysis.RESULTS:Of the 95 enrolled patients(median age 61 years,range 17-85 years),62 patients(65.3%) were male.The median duration of follow-up was 23.7 mo(range 6.0-89.4 mo).Seventy-three patients(76.8%) underwent CE for obscure-overt bleeding.Complete examination of the small bowel was achieved in 77 cases(81.1%).Significant lesions were found in 38 patients(40.0%).The overall rebleeding rate was 28.4%.The rebleeding rate was higher in patients with positive CE(36.8%) than in those with negative CE(22.8%).However,there was no significant difference in cumulative rebleeding rates between the two groups(log rank test;P = 0.205).Anticoagulation after CE examination was an independent risk factor for rebleeding(hazard ratio,5.019;95%CI,1.560-16.145;P = 0.007),regardless of CE results.CONCLUSION:Patients with OGIB and negative CE have a potential risk of rebleeding.Therefore,close observation is required and alternative modalities should be considered in suspicious cases. 相似文献