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81.
目的:建立一种因血管内皮细胞损伤而诱导的大鼠局灶性脑梗死模型。方法:取S—D大鼠11只,分离左侧颈总动脉、颈外动脉和颈内动脉。结扎左颈外动脉远心端,夹闭左翼腭动脉和颈总动脉,经颈外动脉逆行插管并缓慢注入月桂酸钠至颈内动脉系统,造成大脑中动脉血管内皮细胞受损。结果:从模型动物的行为表现、梗死灶形态学和病理学进行考察,10只大鼠均产生一定程度的脑梗死表现,造模成功率为90.9%。结论:该模型的稳定性和重复性较好,能在大脑中动脉的供血区产生恒定的梗死灶,适合进行脑缺血损伤的有关实验研究。 相似文献
82.
中医药结合红外热像仪治疗286例脑供血不足 总被引:2,自引:0,他引:2
目的 探讨红外热像仪产生的热图与中医学的辨证施治相结合治疗脑供血不足。方法 使用红外热像仪对286例脑供血不足患者进行检查,然后中医分型治疗,再每隔1个月用红外热像仪随访疗效。结果 1个月后平均总有效率85.6%,2个月后平均总有效率91.2%,3个月后平均总有效率达95.7%。结论 红外热像仪对早期诊断脑供血不足及疗效跟踪有很大帮助,为临床提供了一种新颖的检查方法。 相似文献
83.
目的研究二氮嗪开放线粒体ATP敏感性钾通道对大鼠脑缺血再灌注细胞凋亡的影响。方法采用线栓法建立大鼠局灶性脑缺血再灌注损伤模型,将20只大鼠随机分成4组,假手术组、缺血组、缺血+二氮嗪治疗组和缺血+二氮嚷+MitoK(ATP)通道特异性抑制剂5-HD组。观察各组凋亡细胞数和凋亡相关蛋白Bcl-2、Bax的变化。结果与缺血组比较,二氮嗪使凋亡细胞数明显减少(83.2±9.04 vs 123.96±13.45),Bcl-2表达增高(0.17±0.01 vs 0.13±0.01),Bax表达下降(0.15±0.02 vs 0.20±0.03),差异具有显著性(P<0.05)。5-HD能取消这些作用(P<0.05)。结论局灶性脑缺血再灌注损伤时,二氮嗪能通过上调半暗带区Bcl-2蛋白表达,下调Bax蛋白表达,减少神经元凋亡,对脑缺血损伤起保护作用。 相似文献
84.
A case of spontaneous thrombosis and infarction leading to death as complications of a cerebral venous malformation in a 13-yearold boy is reported. This is the first published report of this type of complication occurring in a case of venous angioma. While the biologic behavior of cerebral venous malformations has suggested that they are benign in nature, and the results of surgical management have encouraged a conservative approach, the present case illustrates a potential complication and argues against the assumption that these malformations are completely benign in nature. 相似文献
85.
86.
Report on a case of aneurysm in a child and its treatment with discussion of its rarity and origin. 相似文献
87.
不同脑缺血和再灌流过程中大鼠脑组织NO含量的动态变化 总被引:12,自引:0,他引:12
采用线栓法制成大鼠大脑中动脉梗塞 ( MCAO)模型 ,依 Hb O2 - NO法测定持续性脑缺血和缺血 /再灌流脑组织内 NO含量的变化 ,以探讨不同脑缺血和再灌流过程中 NO的变化规律及其意义。结果 :缺血 3小时受损脑组织 NO水平即增高 ,再灌流后 NO逐步升高 ,而持续性缺血状态下 NO则表现降低后再升高的变化。虽然两组 NO在 7天时均有明显降低 ,但仍高于缺血前水平。认为持续性脑缺血和缺血 /再灌流情况下 NO的变化规律有所不同 ,与缺血脑组织的缺氧及产生 NO所需底物供应缺乏有关 ,且可能与脑组织的损害密切相关 相似文献
88.
F. F. Madsen 《Acta neurochirurgica》1990,106(3-4):164-169
Summary Changes in regional cerebral blood flow in anaesthetized pigs with an induced focal cerebral contusion were studied before and after two grades of hyperventilation. A reduction in arterial tension of CO2 with 0.70mmHg and a further reduction of 0.55mmHg did not change the CO2 reactivity. Reactivity in both injured and macroscopically normal regions was the same, revealing an average of 39.3% flow change per kPa change in CO2 tension. Regions with low flow after the contusion had an equally big reduction apparently leading to hypoxia because global metabolic rate was unchanged. 相似文献
89.
Hyperaemia prior to acute cerebral swelling in severe head injuries: The role of transcranial doppler monitoring 总被引:4,自引:0,他引:4
Z. Muttaqin M.D. T. Uozumi S. Kuwabara K. Arita K. Kurisu S. Ohba H. Kohno H. Ogasawara M. Ohtani T. Mikami 《Acta neurochirurgica》1993,123(1-2):76-81
Summary Acute cerebrovascular congestion after a closed head injury is significantly related to intracranial hypertension. As an indirect method of cerebral blood flow measurement, transcranial doppler sonography (TCD) provides a rapid and noninvasive assessment of cerebral haemodynamics, including hyperaemic conditions.TCD examinations was serially performed in 35 patients with severe head injury with intact cerebral circulation; i.e. the mean flow velocity (MFV) patterns of the middle cerebral artery (MCA) did not show signs of cerebral circulatory arrest such as systolic spike, to and fro, or no flow. The results showed that the MFV of the MCAs and ipsilateral extracranial internal carotid arteries (ICAs) in 9 of these patients increased sharply and pulsatility index (PI) decreased during 48–96 hours after the injury. This was soon followed by patterns of high intracranial resistance, consistent with elevated intracranial pressure (ICP) in monitored patients and acute brain swelling on repeated computed tomographic (CT) scans. The correlation between increased MFVs, decreased PIs, and cerebral haemodynamic changes leading to acute brain swelling is discussed.The number of patients who ended with severe disability, vegetative state, or death was 66% in this group of 9 patients, compared to only 34% for the 35 patients overall with severe head injury. Though the morbidity and mortality rates largely depend on the primary injury, the presence of acute cerebral swelling aggravate the grave course in these patients. And the ability of TCD to monitor the hyperaemic state prior to oedema should lead us to adjust the therapy in order to minimize the secondary insult related to intracranial hypertension. 相似文献
90.
David H. Sutherland Kenton R. Kaufman Marilynn P. Wyatt Henry G. Chambers 《Gait & posture》1996,4(4):269-279
Botulinum A toxin (BOTOX®) was injected into the gastrocnemius muscle of 26 cerebral palsy subjects with equinus gait. All subjects were equinus walkers without fixed contracture of the triceps-surae muscle. Injections were performed at 3 month intervals, if needed, as determined by the treating clinician. There were 14 subjects with spastic hemiplegia, 11 subjects with spastic diplegia and 1 subject with spastic quadriplegia. In the case of those subjects with bilateral equinus gait the dose was divided and given into both the right and left gastrocnemius muscle. Gait analysis data was collected prior to the first injection and subsequently at 3 month intervals for 1 year. Kinematic and electromyographic data was obtained. This data was analyzed to provide objective information about the outcome of treatment. Four subjects moved away and were lost to follow-up. Seven subjects left the study to have surgery. The data collected revealed statistically significant improvements in dynamic ankle dorsiflexion in both stance and swing phases, stride length, and electromyography of the tibialis anterior. There were no complications. While the results of this study are promising, additional prospective studies are needed to determine the feasibility of preventing muscle contractures over a longer time period. Furthermore, there is a need for inclusion of other muscles in future research. Future research should also compare BOTOX® treatment with alternative methods of dealing with muscle spasticity such as: casting, orthotic devices, physical therapy, selective dorsal rhizotomy, and surgical lengthening. 相似文献