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81.
本实验以PMSG和hCG处理后黄体细胞萎缩时期大鼠为实验材料,研究黄体萎缩时期黄体细胞羟自由基变化,经HPLC测定hCG注射后7-11天(黄体期)细胞羟自由基含量处于平稳的水平[(0.423±0.08)InM-(0.518±0.117)nM],而在萎缩期间黄体细胞羟自由基含量明显升高[(0。627±0。098)nM-(0.571±0.18)nM],从而在一定方面揭示了黄体萎缩时其体细胞生物学性状的改变,为进一步研究黄体萎缩机制提供了线索. 相似文献
82.
A factor analysis of the rat''s corpus callosum 总被引:1,自引:0,他引:1
Previous work from our laboratory (Berrebi et al., Brain Research, 438 (1988) 216-224) demonstrated region-specific sexual dimorphisms in the size of the rat's corpus callosum, which are modifiable by extra stimulation in early life. These differences are assumed to reflect regional corticocortical fibers of passage which are altered differentially by gender and our experimental manipulations. In this paper, we report our findings when the original data are reanalyzed using a newly developed computer program. This program not only reproduced, with very high accuracy, the original means, but also permitted us to examine computer generated callosal width scores via a factor analysis procedure. Such a procedure yields useful information concerning the clustering of callosal fibers and thus contributes significantly to our hypothesis that discrete cortical regions are selectively sensitive to experimental variables. Factor analyses of the callosal variables and brain weight of 155 rats found 7 width factors, and an eighth factor which contained the variables of brain weight, callosal length, and callosal perimeter. Callosal area did not load significantly on any of these factors. The percentile locations of the width factors, starting at the anterior (genu) end were: widths 1-5, 6-17, 24-38, 46-57, 62-72, 79-95 and 96-99. Use of these factor scores in analyses of variance revealed that the male callosum is wider than the female's, with the differences most pronounced in the genu and the most posterior portion of the splenium. Both age and early handling experience influenced the callosal width factors.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
83.
目的探讨前额叶(prefrontal cortex,PFC)及胼胝体(corpus callosum,CC)的磁共振弥散张量成像(diffusion tensor imaging,DTI)参数各向异性分数(fractional anisotropy,FA)值对老年患者早期POCD的预测价值。方法选取限期腹腔镜下胃癌或结肠癌根治术患者81例,男50例,女31例,年龄≥65岁,ASAⅢ级,根据术后是否发生POCD将患者分为两组:POCD组(n=21)和非POCD组(n=60)。患者于术前1d及术后7d接受DTI检查及认知功能评估,获得FA及神经心理学结果,根据Z计分法判定是否发生POCD,并借助受试者工作特征曲线(receiver operator characteristic curve,ROC)分析术前左、右PFC及CC膝部FA值诊断早期POCD的效能。结果早期POCD发生率为21例(25.93%)。POCD组术前、术后PFC及CC膝部FA值均明显低于非POCD组(P0.05);术前左、右PFC及CC膝部FA值曲线下面积分别为0.757、0.764、0.698,分别明显高于术后FA值曲线下面积0.691、0.694、0.663(P0.05)。结论早期POCD患者术前PFC及CC膝部FA值明显低于非POCD患者,且诊断效能明显高于术后,术前FA值有助于老年胃肠道手术患者早期POCD的预测与评估。 相似文献
84.
85.
孙晓红 《脑与神经疾病杂志》2016,(7):403-405
目的探讨胼胝体梗死(CCI)的高危因素,临床表现及诊断分型。方法分析本院2008年至2013年的12例CCI患者的临床资料。结果 CCI临床表现复杂多样,以肢体瘫痪、语言障碍及智能障碍为主,病变部位以体部及膝部多见,高危因素主要为高血压病及糖尿病。结论 CCI临床表现非特异性,临床诊断需要依靠MRI检查,病因多为动脉粥样硬化基础上的血流动力学改变。 相似文献
86.
Chang JY 《Neuroscience letters》2011,501(3):152-156
Previous studies have reported that intrahemispheric connections between area 17 (V1, striate cortex) and other cortical visual areas are not point-to-point, but instead have some degree of convergence and divergence. Many pathological conditions can interfere with the normal development of patterns of cortico-cortical connections, but there is little information regarding whether or not early pathological insults can also induce permanent changes in the convergence and divergence of cortical connections. Obtaining this information is important because loss of precision in neural projections can contribute to functional deficits and behavioral impairment. In the present study we investigated whether retinal input is required for the development of normal values of convergence and divergence in the visual callosal pathway. We found that enucleation performed at birth induced significant increases in convergence and divergence compared to control animals. In contrast, values of convergence and divergence in rats enucleated at postnatal day 7 (P7) were similar to those in controls. Previous studies have shown that retinal input during the first postnatal week is required for the specification of the overall distribution and internal topography of visual callosal pathways. Our present results therefore extend these previous finding by showing that retinal input during the first postnatal week also specifies the precision of cortico-cortical projections. These findings raise the possibility that the precision of neural connections may be reduced in other pathological conditions that affect early development of neural connections. 相似文献
87.
目的:分析再生障碍性贫血(AA)合并黄体破裂出血的发病原因、临床特点、治疗方法及效果。方法:回顾性分析3例AA合并黄体破裂出血患者的临床资料。结果:3例AA患者,其中2例先后出血2次,1例出血1次。1例经保守治疗.2例经妇科手术治疗后均好转。结论:AA患者合并黄体破裂出血发生率虽不高,但增加了治疗的复杂性,经过积极有效的治疗仍可取得较好的疗效及降低病死率。 相似文献
88.
Margariti PN Blekas K Katzioti FG Zikou AK Tzoufi M Argyropoulou MI 《European radiology》2007,17(2):433-438
The purpose of the study was to evaluate brain myelination by measuring the magnetization transfer ratio (MTR) and to measure
grey (GMV) and white matter volume (WMV) in macrocephalic children with neurofibromatosis type 1 (NF1). Seven NF1 patients
(aged 0.65–16.67 years) and seven age- and gender-matched controls were studied. A three-dimensional (3D) gradient echo sequence
with and without magnetization transfer (MT) prepulse was used for MTR assessment. Volume measurements of GM and WM were performed
by applying segmentation techniques on T2-weighted turbo spin echo images (T2WI). MTR of unidentified bright objects (UBOs)
on T2WI in cerebellar white matter (52.8±3.3), cerebral peduncles (48.5±1.5), hippocampus (52.6±1.1), internal capsule (55.7±0.3),
globus pallidus (52.7±3.9), and periventricular white matter (52.6±1.2) was lower than in the corresponding areas of controls
(64.6±2.5, 60.8±1.3, 56.4±0.9, 64.7±1.9, 59.2±2.3, 63.6±1.7, respectively; p<0.05). MTR of normal-appearing brain tissue in patients was not significantly different than in controls. Surface area (mm2) of the corpus callosum (809.1±62.8), GMV (cm3) (850.7±42.9), and white matter volume (WMV) (cm3) (785.1±85.2) were greater in patients than in controls (652.5±52.6 mm2, 611.2±92.1 cm3, 622.5±108.7 cm3, respectively; p<0.05). To conclude, macrocephaly in NF1 patients is related to increased GMV and WMV and corpus callosum enlargement. MTR
of UBOs is lower than that of normal brain tissue. 相似文献
89.
目的 探讨健康成人胼胝体各部分径值及与年龄的相关性,为相关疾病的诊断提供正常胼胝体数据. 方法 选择120例健康成人自愿者(男、女各半),行头部T1加权序列MR扫描.在正中矢状面上测量胼胝体的膝部、压部、体部的宽度以及胼胝体长度与高度. 结果 120例健康成人胼胝体膝部、压部、体部的宽度以及胼胝体长度与高度分别为(11.35±2.16) mm、(9.97±2.09)mm、(5.93±1.32)mm、(73.33±3.77)mm、(25.34±3.01)mm.经统计学分析发现健康成人腩随年龄的增加胼胝体的膝部、乐部、体部的宽度逐渐减小,而胼胝体的长度与高度随年龄增加而增加,呈显著相关性(P<0.05).胼胝体形态随年龄的增长而呈弓背样增高. 结论 胼胝体的各部分径值及形态与年龄密切相关. 相似文献
90.