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61.
Primary and transplanted ENU induced rat tumors in neurooncology 总被引:1,自引:0,他引:1
H.D. Mennel N. Kosse J.T. Heverhagen H. Alfke 《Experimental and toxicologic pathology》2004,56(1-2):25-35
In neurooncology transplanting, tumors can be used for many purposes e.g. to solve questions concerning the etiology and pathogenesis of such tumors or their management. Experimentally induced and transplanted tumors of the nervous system become reproducible in their morphology and growth parameters after about 12 subsequent intracerebral passages. During the period from the first to the 12th intracerebral generations, a simplification of the histology and a reduction of the induction times take place. Nowadays the growth behavior of such tumors can be followed by imaging methods such as MRI if specially adapted to small animals. Our results are based on the investigation of over 2350 experimentally induced tumors of the central and peripheral nervous system that were diagnosed according to the rules of human and rodent brain tumor classification and various subgroups of this sample, analyzed by electron microscopy, postmortal angiography and MRI. 相似文献
62.
Deep brain stimulation, DBS, is an accepted technique for the treatment of Parkinson's disease. DBS affects the electrical functions of neurons, but exactly how it alters those functions is not clearly explained. An electrical model is determined to simulate treatment with DBS of the sub thalamic nucleus. This model shows the difference in electrical fields between the inside and the outside the neurons. The generated electrical field near the electrodes is high enough to perform an electropermeabilization of the cell membranes, which most likely blockade normal nerve pulses or reduce the nerve impulse speed. Further away from the electrodes activation of large axons is performed. 相似文献
63.
目的:探讨颅脑外伤严重程度及CT征象与预后的关系,并探讨CT复查的最佳时间及临床意义。方法:回顾性分析80例颅脑外伤的严重程度与初次CT征象的关系,统计分析复查CT发现新病变的数目、程度及时间。结果:颅脑外伤的严重程度与初次CT征象符合率为92.5%(74/80)。外伤后即刻昏迷、CT显示重度复合伤、脑干损伤或弥漫性脑白质损伤的病死率达70.0%(21/30)。1~3d复查CT发现迟发性病变80个,4—7d21个,7d后8个。结论:临床病情与CT征象变化对判断预后有重要意义,颅脑外伤后3、7d是复查CT的最佳时机,出现病情变化应随时复查。 相似文献
64.
目的 对重组人脑钠素(rhBNP)用于心脏手术围术期处理的可行性、安全性和有效性进行初步观察,并与硝普钠的作用进行比较。方法 选择择期心脏手术病人22例,随机分为rhBNP组(B组)和硝普钠(SNP)组(s组),每组11例。比较rhBNP与SNP对病人血流动力学和肝肾功能的影响。结果 与给药前和S组比较,B组用药后15、30、60、120和180min各点心输出量增加显著(P〈0.05,P〈0.01);B组与给药前比较,给药后即刻、15、30和60min时点外周血管阻力下降显著(P〈0.05);给药后即刻、15和30点与S组比较,下降显著(P〈0.05)。B组肺毛细血管楔压(PCWP)与用药前比较,用药后即刻、15、30、60、120和180min下降显著(P〈0.05,P〈0.01);与S组比较,给药后30、60、120和180min差异有统计学意义(P〈0.05,P〈0.01)。S组PCWP与用药前比较,用药后60min、120min和180min下降显著(P〈0.05)。B组与输注rhBNP前以及S组比较,平均动脉压、心率和中心静脉压差异均无统计学意义。输注rhBNP后病人24h尿量明显增加。用药过程中以及30d后进行电话随访,未见药物不良反应。结论 rhBNP用于心脏手术围术期处理是可行的,具有改善心功能和稳定循环的作用。 相似文献
65.
Whole-brain echo-planar spectroscopic imaging (EPSI) often substantially lengthens MRI/MRSI (magnetic resonance spectroscopic imaging) protocols. To halve acquisition time, application of a blipped phase-encoding (PE) gradient during the EPSI readout (RO) was previously suggested by PE of the even RO echoes in k-space at an interstitial location along k(PE), separated from the odd RO echoes, effectively reducing the number of PEs by a factor of 2. However, the approach is very susceptible to phase inconsistencies between even and odd RO echoes in the presence of B(0) inhomogeneities and gradient imbalance, leading to ghosting in the PE direction. In this work, the blipped PE gradient is placed in between pairs of even/odd RO gradient lobes to avoid these problems. This approach is demonstrated in a phantom and in normal human brain in vivo at 4T. While the proposed method allows substantial reduction in metabolite ghosting, it may be limited by the presence of a relatively large spurious signal at the Nyquist frequency. 相似文献
66.
老年认知功能障碍与脑结构CT测量的相关性研究 总被引:1,自引:1,他引:0
目的探讨脑萎缩与老年认知功能障碍之间的相关性。方法对开滦集团公司1063名离退休职工进行健康查体,用简易精神状态量表(MMSE)评定认知功能,按分界值将本次研究对象分为认知功能障碍组和认知功能正常组,同时用CT线性测量脑的相关部位以诊断脑萎缩情况,并对各型脑萎缩与认知功能的相关系数及提示老年认知功能障碍的敏感度、特异度、准确度进行分析。结果1063名观察对象中符合入选标准并资料完整者共计511名,其中108名有认知功能障碍,髓质脑萎缩55名、皮质萎缩5名、混合型萎缩30名;认知功能正常者403名,髓质脑萎缩214名、皮质萎缩13名、混合型萎缩62名。认知功能障碍组脑萎缩的发病率高于认知功能正常组,差异具有统计学意义(P<0.005);2组间颞叶海马钩回间距(26.86mm±3.73mmvs25.95mm±3.80mm)及海马钩回间距/大脑左右径的比值(0.21±0.02vs0.20±0.02)差异具有统计学意义(P<0.05);海马钩回间距、皮质脑萎缩、混合型脑萎缩与认知功能障碍呈负相关(分别为r=-0.094,P=0.034,r=-0.156,P≈0.000,r=-0.147,P≈0.000),以海马钩回间距20mm提示老年认知功能障碍的敏感度最高(98.14%),混合型脑萎缩的特异度(84.86%)、准确度最高(72.80%)。结论CT测量相关脑结构,判断脑萎缩类型可以为老年认知功能障碍的诊断提供有价值的信息。 相似文献
67.
68.
LN Weinberger MJ Zirwas JC English III 《Journal of the European Academy of Dermatology and Venereology》2007,21(2):156-162
Male genital oedema can be defined as swelling or the appearance of swelling of the scrotum and/or the penile shaft and prepuce. Despite the various causes of genital oedema reported in the published work, a concise approach to the evaluation and management has not been sufficiently addressed. 相似文献
69.
The aim of this study was to evaluate corneal innervation in soft contact lens wearers using the Tomey Confoscan confocal microscope (40x/0.75 objective lens). Three distinct age- and sex-matched subject groups were involved, including extended soft (hydrogel and silicone-hydrogel) contact lens wearers, overnight soft (hydrogel) contact lens wearers, and non contact lens wearers. A number of variables were objectively measured, subjectively evaluated, or graded in order to investigate the distribution and morphology of corneal nerves. For most of the evaluated parameters, no statistically significant differences were found. However, qualitative observations showed noticeable differences in corneal nerve appearance among the different subject groups; the degree of corneal oedema was suggested as the main causative factor. In conclusion, neither the short-term (overnight wear) nor the long-term (12-month extended wear) soft contact lens wear appeared to affect the morphology and/or distribution of corneal nerves as viewed with confocal microscopy. 相似文献
70.
Yasushi Nishihira Chun‐Feng Tan Junko Hirato Junichi Yoshimura Kenichi Nishiyama Hideaki Takahashi Yukihiko Fujii Hitoshi Takahashi 《Neuropathology》2007,27(6):551-555
Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT. 相似文献