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991.
Radiology of the orbital apex 总被引:1,自引:0,他引:1
The orbital apex, formed by the superior orbital fissure and optic canal, is the cross-road between the orbit and the intracranial structures. Pathological processes may extend intracranially via the superior orbital fissure and vice versa. In addition to intrinsic soft tissue lesions, various pathological processes may involve the surrounding osseous anatomy. Malignant lesions arising from adjacent structures or from haematogeneous metastasis may also infiltrate this region. 相似文献
992.
993.
Antonio G. Carrizo 《Critical Reviews in Neurosurgery》1999,9(2):79-86
Female gender and cigarette smoking appear to be risk factors for the development of multiple intracranial aneurysms. An acquired nature is likely in this form. The mechanism of aneurysm formation in patients with sickle cell anemia is apparently different. These patients also present multiple aneurysms that show propensity for vertebrobasilar territory and appear at a younger age. Familial cerebral aneurysms are diagnosed once heritable connective tissue disorders have been excluded. The age of patients tends to be lower and the size of aneurysm to be smaller at the time of rupture in the familial form. These aneurysms are less frequently found in the anterior communicating artery than the sporadic aneurysms. A high incidence of asymptomatic familial aneurysms was detected in people with family histories of intracranial aneurysms studied by means of magnetic resonance angiography. Furthermore, familial aneurysms are more likely to rupture in families having members with aneurysmal subarachnoid hemorrhage (SAH) than in those without. The results of an interesting study using color "power" transcranial Doppler ultrasound in patients with aneurysmal SAH suggest that as the intracranial pressure diminished, the size of the aneurysm increased, and there was relatively little change between maximum and minimum dimensions during the cardiac cycle, i.e., the pulsatility is reduced. The use of postoperative angiography after clipping is a matter of debate. The indication more widely accepted is in large aneurysms with a wide neck, in which incomplete clipping can be suspected. Taking into account the current low risk of angiography in centers of excellence, its routine use may be recommended. Aneurysm remnants, vessel occlusion, vasospasm, and newly identified aneurysms are the main findings that were reported. 相似文献
994.
Ove Almkvist Bengt Winblad 《European archives of psychiatry and clinical neuroscience》1999,249(3):S3-S9
Alzheimer’s disease (AD) is common in elderly individuals; it causes distress for the patients and their relatives as well as large costs for the society. With the advent of symptomatic treatment at present and probable etiology-based cures in the future, it will be possible to relieve and put an end to these negative effects. Therefore, it is necessary to diagnose the disease as early as possible. In this review, we briefly summarize the state-of-the-art concerning various available clinical and biochemical methods for identifying AD. Increasing age, heritage, and presence of ApoE e4 allele have been confirmed as risk factors for AD as well as some putative factors (e.g., low education, hypertension, hypotension) based on epidemiological recent research. Selective impairment of episodic memory has been found to be a preclinical marker for future development of AD based on convergent data from asymptomatic AD-related mutation carriers, longitudinal studies of patients with mild cognitive impairment (MCI), and epidemiological studies of incident AD cases. Neurophysiological methods are inexpensive and useful for the identification of changes in brain dysfunction in AD and new promising methods are under development. Using magnetic resonance imaging (MRT), structural measurements of brain atrophy and specific brain structures such as the hippocampus have been reported to detect dementia development early in the course of disease. Similarly, functional measurements of brain activity (e.g., blood flow) have revealed that hypometabolism in bilateral parietotemporal brain areas early in the disease course. Finally, biochemical studies have demonstrated that certain proteins (e.g., tau the Aβ1-42/43 metabolite of the amyloid precursor protein) may be associated with the disease process in AD, although the specificity of these markers remains to be established. It is concluded that still no single marker of AD exists, which makes it necessary to rely on data from multiple sources in order to arrive at the best possible diagnosis of AD. 相似文献
995.
烟溶液与温石棉对细胞增殖活性的影响 总被引:3,自引:0,他引:3
目的 探讨香烟烟雾溶液与温石棉单独及联合作用对细胞增殖活性的影响。方法 将人胚肺( H E L) 成纤维细胞用不同浓度的烟溶液和温石棉单独及联合作用一定时间后,应用[3 H] Td R参入法测定了细胞的增殖能力。结果 低剂量的烟溶液与温石棉单独作用时均可促进细胞的增殖,但较高剂量的烟溶液和温石棉则可抑制细胞的增殖;当二者联合作用时,低剂量的烟溶液与温石棉可协同增加细胞的增殖,而较高剂量的烟溶液与温石棉则只表现为相加作用。结论 烟溶液与温石棉单独及联合作用均可影响 H E L细胞的增殖活性,但其促增殖和抑制增殖能力则随剂量不同而不同。 相似文献
996.
维生素A缺乏对小鼠胚胎Hox基因表达的影响 总被引:3,自引:0,他引:3
目的:观察维生素A(VA)缺乏对小鼠胚胎HoxC4(3.5)和HoxD10(4.5)基因表达量的影响。方法:初断乳的昆明小鼠,雌鼠40 只均分为正常对照组(A)和维生素A缺乏组(B),分别饲含VA4000 IU/kg 饲料和VA 0 IU/kg 饲料。雄鼠饲以普通饲料。在饲养的第17 周按雌∶雄= 2∶1 合笼交配。在怀孕的第12 天和第14 天,分别对孕鼠颈椎脱臼处死,立刻剖腹取出胎鼠,迅速置于液氮中速冻后置于- 70℃冰箱保存。用地高辛标记的探针,采用原位杂交方法探测小鼠胎儿HoxC4(3.5)和HoxD10(4.5)基因m RNA含量。结果:VA缺乏时,m RNA的含量明显减少。结论:VA缺乏导致Hox 基因表达量下降,从而影响小鼠胚胎的正常发育。 相似文献
997.
维生素A缺乏对大鼠胚胎生长发育的影响 总被引:3,自引:0,他引:3
本文观察了维生素A缺乏对大鼠胚胎生长发育的影响。结果显示:维生素A缺乏使胎鼠的体重,身长,尾长明显小于对照组,囟门明显大于对照组,且维生素A缺乏组第2、5、6胸骨残缺以及前爪骨化不完全者明显较多。脑淤血、脑水肿以及肾盂积水者也明显较多。维生素A缺乏严重地影响了大鼠胚胎的正常生长发育。 相似文献
998.
目的 探讨增殖细胞核抗原(PCNA)与胃癌生物学行为的关系。方法 应用流式细胞术,对68例胃癌及癌旁组织细胞中PCNA的表达进行了检测,结果 PCNA在胃癌中的表达明显高于正常胃粘膜及癌旁组织;PCNA指数与胃癌分化化程度及肿瘤浸润深度有关(P〈0.05),结论 检测PCNA的表达有助于发现早期癌变及有判断胃癌的生物学选择性。 相似文献
999.
直肠电刺激对上运动神经元损伤后痉挛状态的疗效研究 总被引:1,自引:0,他引:1
研究直肠电刺激(RPES)对上运动神经元损伤后痉挛状态的疗效。对10例脊髓损伤(SCI)后痉挛患者,10例偏瘫后痉挛患者进行RPES治疗,在治疗前及治疗后1h,对SCI患者双下肢、偏瘫患者患侧下肢进行康复评分和步态、步行能力观察。结果:经RPES治疗后,SCI患者下肢Ashworth评分、Clonus评分显著降低,患者出现步态改善和步行能力提高,偏瘫患者患侧下肢康复评分无显著变化。采用RPES治疗,对降低SCI后痉挛状态有较好的疗效,对偏瘫后痉挛状态无明显治疗作用。 相似文献
1000.
高压氧治疗小儿重型颅脑损伤(附68例报告) 总被引:2,自引:0,他引:2
68例小儿重型颅脑损伤,在常规治疗基础上加用高压氧治疗32例,治愈率达719%,总有效率96.9%。与常规治疗组相比,疗效明显提高,经统计学处理有明显差异(P<001)。 相似文献