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91.
PURPOSE: To detect the abnormalities of gray matter in children with amblyopia by voxel-based morphometry (VBM). DESIGN: Prospective, nonrandomized clinical trial. METHODS: Thirteen children with amblyopia and 14 normally sighted children underwent magnetic resonance (MR) examination. The two groups were age-matched with a mean age of 5.8 years. In the amblyopia group, five children had strabismus amblyopia, and eight had anisometropic amblyopia. We analyzed the original 3-dimensional T1 brain images using the VBM module within the widely used analysis software package SPM2 (Welcome Department of Cognitive Neurology, London, United Kingdom). After normalization, segmentation, and smoothing of the images, comparison between amblyopic and control groups was derived for the gray matter of the entire brain using parametric statistics. RESULTS: The results of VBM analysis indicated that the amblyopic group had decreased gray matter density in the middle frontal gyrus, parahippocampal gyrus, fusiform gyrus, inferior temporal gyrus of the left hemisphere, and the bilateral calcarine cortices. The radii of these regions ranged from 12 to 36 voxels. These abnormalities were consistent with morphologic changes in brain regions related to visual function. CONCLUSIONS: Using MR and VBM analysis, we detected morphologic changes in the visual cortex of children with amblyopia, which may indicate developmental abnormalities of visual cortex during the critical growth period.  相似文献   
92.
93.
青阳参甙是一种已用于临床,对癫痫病有较好疗效的药物,其二乙酰甙元的立体分子结构用x射线衍射方法进行了测定,并与几种作用于神经系统药物的分子结构作了对比,还讨论了它们共同具有的相似的活性基团。  相似文献   
94.
白首乌化学成分的研究   总被引:4,自引:0,他引:4  
自白首乌主要品种耳叶牛皮消(Cynanchum auriculatum Royle ex Wight)根中首次分得三个已知甾体酯型甙元:告达亭(caudatin),开德甙元(kidjolanin),萝藦甙元(Metaplexigenin)和一种新的二苯酮衍生物(Ⅳ),经光谱分析推定其结构为2,6,2′,5′-四羟基,3-乙酰基,6′-甲基二苯酮,命名白首乌二苯酮。  相似文献   
95.
目的:观察推拿在全髋关节置换术后康复治疗中的临床疗效。方法:将60例患者随机分成治疗组和对照组。治疗组30例进行推拿结合康复治疗,对照组30例进行单纯康复治疗。两组均治疗2星期。分别观察两组患者术后7天、术后2星期、术后6星期的改良人工髋关节Harris量表及汉密尔顿焦虑量表(Hamilton Anxiety Rating Scale,HAMA)。结果:Harris量表评分总分,两组组内患者不同时间点多重比较差异有统计学意义(P〈0.05);术后1天、术后7天及术后6星期两组间比较,差畀均无统计学意义(A,0.05);术后2星期两组间比较差异有统计学意义(P〈0.05)。HAMA量表两组组内患者不同时间点多重比较差异有统计学意义(P〈0.05);术后1天两纽间评分无显著性差异(P〉0.05);术后7天、术后2星期、术后6星期两组间评分均有显著性差异(P〈0.05)。结论:单位时间内,推拿结合康复治疗对全髋关节置换术后患者的疼痛、关节活动范围及焦虑等方面的改善作用优于单纯康复治疗。  相似文献   
96.
Based on the theory of magnetoacoustic coupled dynamics, the purpose of this paper is to evaluate the dynamic stress concentration near an elliptical opening in exponential-gradient piezomagnetic materials under the action of antiplane shear waves. By the wave function expansion, the solutions for the acoustic wave fields and magnetic fields can be obtained. Stress analysis is performed by the complex function method and the conformal mapping method, which are used to solve the boundary conditions problem, and is used to express the dynamic stress concentration coefficient (DSCC) theoretically. As cases, numerical results of DSCCs are plotted and discussed with different incident wave numbers and material parameters by numerical simulation. Compared with circular openings, elliptical openings are widely used in material processing techniques and are more difficult to solve. Numerical results show that the dynamic stress concentration coefficient at the elliptical opening is strongly dependent on various parameters, which indicates that the elliptical opening is more likely to cause crack and damage to exponential-gradient piezomagnetic materials.  相似文献   
97.
Diffuse Large B Cell Lymphoma (DLBCL), the most common form of blood cancer. The genetic and clinical heterogeneity of DLBCL poses a major barrier to diagnosis and treatment. Hence, we aim to identify potential biomarkers for DLBCL.Differentially expressed genes were screened between DLBCL and the corresponding normal tissues. Kyoto Encyclopedia of Genes and Genomes and Gene oncology analyses were performed to obtain an insight into these differentially expressed genes. PPI network was constructed to identify hub genes. survival analysis was applied to evaluate the prognostic value of those hub genes. DNA methylation analysis was implemented to explore the epigenetic dysregulation of genes in DLBCL.In this study, Kinesin family member 23 (KIF23) showed higher expression in DLBCL and was identified as a risk factor in DLBCL. The immunohistochemistry experiment further confirmed this finding. Subsequently, the univariate and multivariate analysis indicated that KIF23 might be an independent adverse factor in DLBCL. Upregulation of KIF23 might be a risk factor for the overall survival of patients who received an R-CHOP regimen, in late-stage, whatever with or without extranodal sites. Higher expression of KIF23 also significantly reduced 3, 5, 10-year overall survival. Furthermore, functional enrichment analyses (Kyoto Encyclopedia of Genes and Genomes, Gene oncology, and Gene Set Enrichment Analysis) showed that KIF23 was mainly involved in cell cycle, nuclear division, PI3K/AKT/mTOR, TGF-beta, and Wnt/beta-catenin pathway in DLBCL. Finally, results of DNA methylation analysis indicated that hypomethylation in KIF23''s promoter region might be the result of its higher expression in DLBCL.The findings of this study suggested that KIF23 is a potential biomarker for the diagnosis and prognosis of DLBCL. However, further studies were needed to validate these findings.  相似文献   
98.
ObjectiveTo compare the results and 5- and 8-year overall survival (OS) and disease-free survival (DFS) of hand-assisted laparoscopic surgery (HALS) and laparoscopic-assisted surgery (LAS) in radical gastrectomy for advanced distal gastric cancer.MethodsA total of 124 patients admitted to our institution from May 2009 to April 2013 were randomly divided into a HALS group (n = 62) and a LAS group (n = 62). Postoperatively, 110 patients were followed for 5 and 8 years, and 14 patients were lost to follow-up. The 5- and 8-year OS and DFS rates of the groups were compared and analyzed.ResultsThe 5- and 8-year OS rates, respectively, were 38.8% and 19.4% in the HALS group and 38.3% and 15.3% in the LAS group (log-rank test, χ2 = 0.250). The 5- and 8-year DFS rates, respectively, were 23.1% and 10.6% in the HALS group and 19.3% and 11.6% in the LAS group (log-rank test, χ2 = 0.109). No significant differences were found.ConclusionCompared with LAS, HALS radical gastrectomy for advanced distal gastric cancer had a lower conversion rate to open surgery, shorter surgical duration, and more thorough dissection of lymph nodes; 5- and 8-year OS and DFS rates were similar to those with LAS.  相似文献   
99.
Cardiovascular disease (CVD) is a group of diseases affecting the heart and blood vessels and is the leading cause of morbidity and mortality worldwide. Increasingly more evidence has shown that the senescence of vascular endothelial cells is the key to endothelial dysfunction and cardiovascular diseases. Anthocyanin is a type of water-soluble polyphenol pigment and secondary metabolite of plant-based food widely existing in fruits and vegetables. The gut microbiome is involved in the metabolism of anthocyanins and mediates the biological activities of anthocyanins and their metabolites, while anthocyanins also regulate the growth of specific bacteria in the microbiota and promote the proliferation of healthy anaerobic flora. Accumulating studies have shown that anthocyanins have antioxidant, anti-inflammatory, and anti-aging effects. Many animal and in vitro experiments have also proven that anthocyanins have protective effects on cardiovascular-disease-related dysfunction. However, the molecular mechanism of anthocyanin in eliminating aging endothelial cells and preventing cardiovascular diseases is very complex and is not fully understood. In this systematic review, we summarize the metabolism and activities of anthocyanins, as well as their effects on scavenging senescent cells and cardioprotection.  相似文献   
100.
本文介绍一种用流态化技术与喷雾干燥相结合的方法将苯甲酸钠溶液在流化床内完成蒸发、干燥与造粒。  相似文献   
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