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991.
992.
L. T. Bilaniuk P. T. Molloy R. A. Zimmerman P. C. Phillips S. N. Vaughan G. T. Liu L. N. Sutton M. Needle 《Neuroradiology》1997,39(9):642-653
We describe the clinical and imaging findings of brain stem tumours in patients with neurofibromatosis type 1 (NF1). The
NF1 patients imaged between January 1984 and January 1996 were reviewed and 25 patients were identified with a brain stem
tumour. Clinical, radiographical and pathological results were obtained by review of records and images. Brain stem tumour
identification occurred much later than the clinical diagnosis of NF1. Medullary enlargement was most frequent (68 %), followed
by pontine (52 %) and midbrain enlargement (44 %). Patients were further subdivided into those with diffuse (12 patients)
and those with focal (13 patients) tumours. Treatment for hydrocephalus was required in 67 % of the first group and only 15
% of the second group. Surgery was performed in four patients and revealed fibrillary astrocytomas, one of which progressed
to an anaplastic astrocytoma. In 40 % of patients both brain stem and optic pathway tumours were present. The biological behaviour
of brain stem tumours in NF1 is unknown. Diffuse tumours in the patients with NF1 appear to have a much more favourable prognosis
than patients with similar tumours without neurofibromatosis type 1.
Received: 21 November 1996 Accepted: 22 December 1996 相似文献
993.
994.
研究消炎痛及乙胺嗪对家兔肺、脑血管和大鼠脑微动脉缺氧反应的影响。发现吸入10%氧使家兔肺血管阻力(PVR)增加,脑血管阻力(CVR)降低,大鼠脑微动脉扩张。用消炎痛明显增强家兔缺氧性肺、脑血管反应。△PVR%由用药前26.6±16.7%增至44.2±7.7%;△CVR%则由一12.9±4.5%减至-30.7±4.7%;大鼠微动脉直径增大率(△D%)由用药前28.2±2.0%增至41.3±5.8%;用乙胺嗪则使缺氧时△PVR%由 84.6±18.1%降至 23.8±8.5%;△CVR%由-16.7±4.5%变为 6.9±2.8%;△D%由 29.7±5.8%减至 25.6±5.0%。结果表明前列腺素在缺氧性肺血管收缩反应及脑血管扩张反应中起调节作用,而白三烯则在缺氧性肺血管收缩反应中起介导作用。 相似文献
995.
Retrograde air insufflation in MRI: A technical note 总被引:2,自引:0,他引:2
Retrograde air insufflation was employed to distend the colon and the ileum in 18 patients and five volunteers for magnetic resonance examination. Good and moderate marking of the ileum was obtained in 18 cases. The colon was nearly completely distended in every case. Intraluminal tumor, mural thickening, and extraluminal lesion were outlined by intraluminal air and surrounding air-distended bowel. This study shows that retrograde air insufflation is a useful method to mark the colon and most parts of the ileum. 相似文献
996.
997.
998.
Serum LPO content was measured by means of TBA in 41 patients suffering from craniocerebral injury in present study. The relationships between OFR and progressing course of craniocerebral injury, level of LPO and patient condition of an injury and prognosis were analysed. Results showed that serum LPO increased obviously in 24 hours after injury. The more severe the condition of an injury was, the higher the serum LPO content was, the worse prognosis would be. Serum LPO content increased statistically in group of death in 24 to 72 hours after injury, while it didn't change significantly in group of survival. The author suggest that the reaction of OFR enhanced after craniocerebral injury, and which was an important factor giving rise to secondary brain injury. Measurement of serum LPO content plays an important role in estimating the patients condition of injury and their prognosis. 相似文献
999.
1000.
日本血吸虫感染小鼠脾细胞IL—2及IFN—γ动态观察 总被引:4,自引:0,他引:4
本文观察8wk龄C57BL/6小鼠感染日本血吸虫尾蚴后不同时期脾细胞经SEA或ConA刺激,体外诱生的IL-2和IFN-γ活性变化。结果表明两种细胞因子活性均在感染后第4-6wk开始上升,第6—8wk达高峰,第12—14wk恢复至感染前水平。IFN-γ高峰时间略先于IL-2。非特异性刺激原诱生组和特异性刺激原诱生组各阶段细胞因子活性动态基本一致,前组活性高于后组。提示IFN-γ与IL-2活性与血吸虫卵肉芽肿的诱导、成熟与维持有密切关系。 相似文献