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11.
四叠体池蛛网膜囊肿   总被引:2,自引:0,他引:2  
目的:探讨四叠体池蛛网膜囊肿的临床特征和治疗方法。方法:对11例四叠体池蛛网膜囊肿进行了回顾性总结分析。所采用的手术方法有:①脑室分流手术;②囊肿-腹腔分流术;③囊肿切除;④囊肿切除加囊肿-脑池分流术,或囊肿部分切除(即囊肿开窗术),或囊肿切除加脑室-脑池分流术。结果:其主要临床表现以颅内压增高症和中线综合征为主。上述方法中单纯囊肿壁切除只能使部分病人的病情缓解,脑室分流或囊肿切除加脑室分流手术的疗效较好。结论:四叠体区蛛网膜囊肿常合并梗阻性脑积水,单纯囊肿切除不能解除多数病人的梗阻性脑积水。作者根据囊肿是否与蛛网膜下腔相通提出:对交通性蛛网膜囊肿采用单纯性脑室分流术,对非交通性者采用囊肿切除加脑室分流手术的治疗方法。  相似文献   
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Adult female rats were i.p. infused (Alzet osmotic minipumps) with neurotensin (NT, 2 micrograms/rat/day for 7 days), arginine-vasopressin (AVP, 2 micrograms/rat/day for 8 days), bombesin (BM, 0.75 microgram/rat/day for 7 days) or injected with neuropeptide Y (NPY, 0.5 microgram/rat twice a day for 4 days). NT infusion increased absolute and relative thyroid gland weight and decreased serum T4 level, while serum TSH and T3 levels remained unchanged. AVP treatment increased thyroid gland weight and serum TSH and T4 levels and a similar effect was induced by prolonged BM infusion. On the other hand, NPY administration had no effect either on thyroid gland weight or on serum TSH, T4 and T3 levels. Results of the present study thus clearly demonstrate a potent stimulatory action of AVP and BM on thyroid gland function and suggest that this effect is mediated by the pituitary gland. On the contrary, prolonged NT infusion decrease serum T4 level while NPY had no effect on thyroid gland function.  相似文献   
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The promoting effect of the Chinese medicinal herb, Wikstroemia chamaedaphne and Tung oil extracts (WC and HHPA) on carcinoma of uterine cervix induced by HSV-2 or MCA in mice was studied. The results showed that WC and HHPA extracts were not carcinogenic themselves. After carcinogen HSV-2 and MCA treatment, WC and HHPA were added separately. The inducing rates by HSV-2 increased from 7.4% to 21.1% and 26.3%, those by MCA increased from 56.5% to 82.8% and 84.4%. There was a significant difference between the combined groups and groups with HSV-2 or MCA only. The experimental results suggest that these two kinds of extracts play a promoting effect on carcinogenesis. The relation between the carcinogenesis of uterine cervix or nasopharynx and WC or HHPA extracts is discussed.  相似文献   
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将动、静脉阻断法用于恒速灌流的在体山羊左肺,使其总压力降区分为动脉端、静脉端及中间段三部分。大肠杆菌内毒素主要升高肺静脉端压力降及肺毛细血管压;山莨菪碱可显著缓解内毒素所致的改变,但对正常肺血管各段压力降无明显影响。5-羟色胺主要升高肺动脉端压力降,对肺静脉端及毛细血管压无明显影响。去甲肾上腺素及组胺主要升高肺静脉端压力降及肺毛细血管压,但对肺动脉端无明显影响。去甲肾上腺素和组胺可能介导内毒素性肺动脉高压。  相似文献   
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Recent studies have suggested that aldosterone plays a role in the pathogenesis of renal injury. In this study, we investigated whether local angiotensin II (Ang II) activity contributes to the progression of renal injury in aldosterone/salt-induced hypertensive rats. Uninephrectomized rats were treated with 1% NaCl in a drinking solution and one of the following combinations for 6 weeks: vehicle (2% ethanol, s.c.; n=9), aldosterone (0.75 mug/h, s.c.; n=8), aldosterone+Ang II type 1 receptor blocker olmesartan (10 mg/kg/day, p.o.; n=8), or aldosterone+olmesartan (100 mg/kg/day, p.o.; n=9). Aldosterone/salt-treated hypertensive rats exhibited severe proteinuria and renal injury characterized by glomerular sclerosis and tubulointerstitial fibrosis. Aldosterone/salt-induced renal injury was associated with augmented expression of angiotensin converting enzyme and Ang II levels in the renal cortex and medullary tissues. Renal cortical and medullary mRNA expression of transforming growth factor-beta (TGF-beta) and connective tissue growth factor (CTGF) as well as the collagen contents were increased in aldosterone/salt-treated hypertensive rats. Treatment with olmesartan (10 or 100 mg/kg/day) had no effect on blood pressure but attenuated proteinuria in a dose-dependent manner. Olmesartan at 10 mg/kg/day tended to decrease renal cortical and medullary Ang II levels, TGF-beta and CTGF expression, and collagen contents; however, these changes were not significant. On the other hand, an ultrahigh dose of olmesartan (100 mg/kg/day) significantly decreased these values and ameliorated renal injury. These data suggest that augmented local Ang II activity contributes, at least partially, to the progression of aldosterone/salt-dependent renal injury.  相似文献   
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Glial glutamate transporter-1 (GLT-1) plays an essential role in removing glutamate from the extracellular space and maintaining the glutamate below neurotoxic level in the brain. To explore whether GLT-1 plays a role in the acquisition of brain ischemic tolerance (BIT) induced by cerebral ischemic preconditioning (CIP), the present study was undertaken to observe in vivo changes in the expression of GLT-1 and glial fibrillary acidic protein (GFAP) in the CA1 hippocampus during the induction of BIT, and the effect of dihydrokainate (DHK), an inhibitor of GLT-1, on the acquisition of BIT in rats. Immunohistochemistry for GFAP showed that the processes of astrocytes were prolonged after a CIP 2 days before the lethal ischemic insult, which could protect pyramidal neurons in the CA1 hippocampus against delayed neuronal death induced normally by lethal ischemic insult. The prolonged processes extended into the area between the pyramidal neurons and tightly surrounded them. These changes made the pyramidal layer look like a 'shape grid'. Simultaneously, the prolonged and extended processes showed a great deal of GLT-1. Western blotting analysis showed significant upregulation of GLT-1 expression after the CIP, especially when it was administered 2 days before the subsequent lethal ischemic insult. Neuropathological evaluation by thionin staining showed that DHK dose-dependently blocked the protective role of CIP against delayed neuronal death induced normally by lethal brain ischemia. It might be concluded that the surrounding of pyramidal neurons by astrocytes and upregulation of GLT-1 induced by CIP played an important role in the acquisition of the BIT induced by CIP.  相似文献   
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