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81.
神经导航辅助显微手术治疗脑功能区肿瘤 总被引:6,自引:2,他引:4
目的探讨神经导航系统辅助下脑重要功能区肿瘤显微手术的治疗效果和应用价值。方法1999年12月~2002年6月应用StealthStation神经导航系统辅助切除邻近脑重要功能区肿瘤10例,对神经导航系统术中应用的优越性、精确性等进行分析。结果本组平均注册误差为(2.8±0.9)mm,肿瘤和重要解剖功能结构定位准确,肿瘤全切除率77.8%。术后神经功能未受明显影响,无手术并发症及死亡。结论神经导航系统对于切除邻近脑重要功能区肿瘤具有定位准确,动态示踪和实时导航,侵袭性小,安全、可靠等特点,有助于提高肿瘤全切率及降低手术并发症。 相似文献
82.
83.
目的 探讨原发性中枢神经系统淋巴瘤的临床特点、诊断及治疗方法。方法 回顾性分析35例原发性中枢神经系统淋巴瘤的临床资料、病理特征及术前诊断方法。结果 本组男19例,女16例,男女比例为1.2:1。年龄26~72岁,平均年龄52岁。所有患者人免疫缺陷病毒(HIV)检查均为阴性。临床症状主要表现为颅内压增高、肢体无力、瘫痪和神经精神症状。57%的患者病史短于4周,发病急,病情进展快。肿瘤多位于额部、颚顶部和基底节区,本组共35例52个肿瘤,其中16例为多发性肿瘤(45.7%)。结论 原发性中枢神经系统淋巴瘤是一组异质性肿瘤,侵袭性大。病史短,发病急,病情进展快,常发生于幕上大脑半球,易多发,术前诊断困难.预后差. 相似文献
84.
Identification of the C-terminal flanking peptide of preprocholecystokinin in rat brain by a novel radioimmunoassay 总被引:1,自引:0,他引:1
The C-terminal flanking peptide of preprocholecystokinin (preproCCK) has been identified in extracts of rat brain using a novel radioimmunoassay. There is a single form of immunoreactive material on gel filtration, ion exchange and reversed-phase HPLC. The C-terminal preproCCK immunoreactivity had a similar pattern of distribution to CCK8 in different regions of rat brain. This assay should help in studies of neuronal CCK biosynthesis. 相似文献
85.
Heterogeneity among the spinocerebellar ataxias (SCA) has been shown on clinical, biochemical, and genetic criteria. Among the autosomal dominant SCAs, several kindreds have shown loose linkage to the HLA loci on chromosome 6, while linkage in other kindreds has been rejected. The advent of multipoint linkage analysis allows the use of several marker loci simultaneously, thus increasing the amount of usable information. We have reanalyzed linkage data from a large kindred with SCA and provide evidence for a telomeric location of the SCA gene in this family. Knowledge of the relative gene location will ease the identification of the SCA gene by reducing the size of the chromosomal regions that must be examined. 相似文献
86.
D. A. CROOKS 《Neuropathology and applied neurobiology》1991,17(5):421-424
The quantitation of diffuse axonal injury provides a more objective approach to the assessment of tissue damage in head injuries. The method designed in this study takes into account the anisotropy and structural inhomogeneity of the brain, and the distribution of lesions in diffuse axonal injury. The number of counts required for the statistical analysis is inversely proportional to the square of the desired accuracy, specified as the percentage of the mean value of the axonal balloons since the true mean is unknown from the outset. The number of fields are examined using an indexed-squares graticule in 10 different areas of the brain. Silver-stained sections from the brains of head injured patients that survived longer than 12 h must be used with this method. Difficulties may arise when patients of different survival times are compared since it takes some time for the axonal balloons to develop. A correlation with the survival time can be established with the quantitative data collected. The morphometric principles and the statistical rationale on which this methodology is based are briefly presented. 相似文献
87.
Manfred Schmidt Leslie Van Ekeris Barry W. Ache 《The Journal of comparative neurology》1992,318(3):277-290
The organization of sensory afferents in the antennular nerve (AN) of the spiny lobster and the central arborization of the afferents in the lateral and medial antennular neuropils (LAN, MAN) were analyzed by backfilling the AN with biocytin. The MAN receives primarily thick afferents (diameter ≥ 10 μm) with a consistent pattern of arborization from the medial of the three major divisions of the AN. The LAN, in contrast, receives many thin to medium-sized afferents (diameter ≤ 0.3–5 μm), in addition some with diameters ≥ 5 μm, from the lateral and dorsal divisions of the AN. In contrast to the consistent pattern of arborization in the MAN, afferents projecting to the LAN arborize in widely different patterns. Serially arranged, orthogonal side branches that are suggestive of topographical representation of the serially arranged sensilla on the antennule contribute to the stratification of the LAN. Together with existing electrophysiological data, these morphological findings are consistent with the idea that the MAN receives primarily mechanosensory (largely statocyst) input, as previously thought, but that the LAN receives chemosensory as well as mechanosensory input. The chemosensory input to the LAN would represent a novel pathway for processing chemosensory input from the antennule. 相似文献
88.
O. Pranevicius K. Bertasius M. Pranevicius E. Jarzemskas 《Acta neurologica Scandinavica》1992,86(5):512-516
The dynamics of the speed of transcranial propagation of ultrasonic impulses has been established in humans. The possibility of detecting the changes in mechanical state of intracranial structures by dynamic measurement of the time of transcranial propagation of ultrasonic impulses (TUPT) has been ascertained for 10 healthy persons and 11 patients with different neurological pathology. The cerebrospinal fluid pressure (CSFP) was simultaneously monitored for 4 of the patients. Spontaneous fluctuations in TUPT and the changes caused by jugular veins, inferior vena cava compression, hyperventilation and temporary retention of breathing were detected for all investigated subjects. Spontaneous TUPT changes in the range of 0.25-0.85 x 10(-4) of initial mean value, which are related with cardiac and respiratory cycles, have been found in healthy persons while in patients they ranged from 0.07 x 10(-4) to 4.5 x 10(-4) of mean time. In healthy persons bilateral jugular vein compression leads to a decrease in TUPT by 1.8-3.0 x 10(-4), while the compression of inferior vena cava gives an increase in TUPT by 1.6-2.6 x 10(-4). Changes in TUPT during these maneuvers in neurological patients were found to be of different amplitude and direction. The rise of CSFP by 8.4-20.2 mmHg (mean 12.4 mmHg) was observed in 4 investigated patients during the compression of jugular veins or during the inferior vena cava compression, while the changes in TUPT obtained during each of such maneuvers were of opposite character. The results suggest that dynamic evaluation of acoustic impedance of intracranial system reflects the changes in the mechanical state of brain parenchyma. 相似文献
89.
Dr. Elina Ikonen Armi Salo Mirja Somer Hannu Somer Leena Pääkkönen Leena Peltonen 《American journal of medical genetics. Part A》1992,43(4):753-758
A 15-year-old boy with a terminal deletion of the short arm of chromosome 4 is described. The patient has a mild clinical phenotype that is incompatible with Wolf-Hirschhorn syndrome. Careful neurological examination including CT scan did not show any signs of Huntington disease. The chromosomal breakpoint was analyzed by means of polymorphic DNA probes localized close to the tentative Huntington (HD) locus. The breakage has occurred between D4S43 and D4S90 loci and thus deletes part of the chromosomal candidate regions for the HD locus. © 1992 Wiley-Liss, Inc. 相似文献
90.
Perfusion is a crucial physiological parameter for tissue function. To obtain perfusion-weighted images and consequently to measure cerebral blood flow (CBF), a newly developed flow-sensitive alternating inversion recovery (FAIR) technique was used. Dependency of FAIR signal on inversion times (TI) was examined; signal is predominantly located in large vessels at short TI, whereas it is diffused into gray matter areas at longer TI. CBF of gray matter areas in the human brain is 71 ± 15 SD ml/100 g/min (n = 6). In fMRI studies, micro- and macrovessel inflow contributions can be obtained by adjusting TIs. Signal changes in large vessel areas including the scalp were seen during finger opposition at a TI of 0.4 s; however, these were not observed at a longer TI of 1.4 s. To compare with commonly used BOLD and slice selective inversion recovery techniques, FAIR and BOLD images were acquired at the same time during unilateral finger opposition. Generally, activation sites determined by three techniques are consistent. However, activation of some areas can be detected only by FAIR, not by BOLD, suggesting that the oxygen consumption increase couples with the CBF change completely. Relative and absolute CBF changes in the contralateral motor cortex are 53 ± 17% SD (n = 9) and 27 ± 11 SD ml/100 g/min (n = 9), respectively. 相似文献