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Summary ? Background. Cerebral vasospasm after subarachnoid hemorrhage (SAH) has remained a major cause of morbidity and mortality in patients with SAH. Excitatory neurotransmitters are gathered in the extracellular space during ischemia due to cerebral vasospasm and initiate or stimulate a series of pathophysiological biochemical processes which consequently lead to neuronal death. Tizanidine (Sandoz compound DS 103–282, 5-chloro-4,2 (2-imidazolin-2-yl-amino)-2,1,3-benzothiazol hydrochloride) is a centrally-acting muscle relaxant and a selective α 2 adrenoreceptor agonist which shows its effect by stimulating presynaptic α 2 adrenoreceptors in central ASPergic and GLUergic system by inhibiting aspartic acid and glutamic acid release. In this study, the effect of Tizanidine on vasospasm was evaluated.  Methods. We used a femoral artery vasospasm model in rats which has been described by Okada et al. 60 rats were examined in three groups. The first group was used as control group (Control) (n=20), in the second group subarachnoid hemorrhage was performed (SAH) (n=20), in the third group Tizanidine was administered in addition to SAH (SAH+Tizanidine administration) (n=20). Animals in SAH+Tizanidine administration group received 0,3 mg/kg/day intraperitoneally for 7 days. Seven days after the experiment, after perfusion-fixation, 10 mm segments of both femoral arteries were removed and the femoral artery was prepared for light microscope examination, scanning and transmission electron microscopy and for morphometric analysis.  Results. There was a statistically significant difference between the electron, scanning and light microscopic observations and morphometric analysis of SAH+Tizanidine administration group and SAH group, and no statistically significant difference between SAH+Tizanidine administration group and control group.  Conclusion. This study has disclosed that Tizanidine administration before the vasospasm reduces ultrastructural and morphometric vasospastic insult significantly. However, the clinical application of Tizanidine as a protective and therapeutic agent in cerebral vasospasm needs further studies including the employment of clinically more relevant SAH models.  相似文献   
94.
Mesoatrial shunt in Budd-Chiari syndrome   总被引:2,自引:0,他引:2  
BACKGROUND: The operations with proven effects on survival in Budd-Chiari syndrome are shunt operations and liver transplantation. PATIENTS AND METHODS: Between 1993 and 1999 (June), 13 cases of Budd-Chiari syndrome have been treated surgically. Four cases had concomitant thrombosis of the inferior vena cava; the others had marked narrowing of the lumen due to the enlarged caudate lobe. Mesoatrial (n = 12) or mesosuperior vena caval (n = 1) shunts were constructed with ringed polytetrafluoroethylene grafts. RESULTS: The median portal pressure fell from 45 (range 32 to 55) to 20 (range 11 to 27) cm H(2)O (P <0.001). Two patients died in the early postoperative period. One patient who did not comply with anticoagulant treatment had a shunt thrombosis in the second postoperative year. The other 10 patients are alive without problems during a median 42 (range 1 to 76) months of follow-up. CONCLUSION: Mesoatrial shunt with a ringed polytetrafluoroethylene graft is effective in Budd-Chiari syndrome cases with thrombosis or significant stenosis in the inferior vena cava.  相似文献   
95.
BACKGROUND: Nitric oxide (NO) may have an important role in the healing of burn wounds. This study investigated the effect of NO on experimentally induced burn wounds by preventing NO synthesis. METHODS: A total of 40 mice weighing 25 to 30 g were used in this study. The shaved skin on the back of the mice was immersed in 100 degrees C water for 10 seconds to achieve a partial-thickness scald burn. The mice were divided into two groups of 20. In group I (control group), 17.5 mg/kg of serum physiologic (placebo) was injected intraperitoneally two times a day for 15 days. In group II (study group), 17.5 mg/kg of aminoguanidine (NO synthase inhibitor) was injected intraperitoneally two times a day for 15 days. On day 15 of the burn, the animals were killed and the burn areas were investigated histologically. Histologic changes such as epithelial proliferation, abscess, collagen, and granulation tissue were evaluated. RESULTS: Epithelial proliferation, formation of collagen, and granulation tissue with rich capillaries observed in the control group were statically significantly higher than those observed in the study group (z = -2.022, p < 0.05; z = -2.02, p < 0.05; and z = -2.022, p < 0.05; respectively). CONCLUSION: We concluded that healing of the burn wound is delayed by preventing NO synthesis.  相似文献   
96.
BACKGROUND: Ependymomas, the common glial tumors of the spinal cord, occur occasionally outside the central nervous system and are called exstraspinal ependymomas (EEP). EEPs are found primarily in sacrococcygeal region during childhood. The pathogenesis and the treatment of the sacrococcygeal (SC) ependymomas are still controversial. Therefore, we present our case with metaanalysis of other case reports to determine the optimal treatment modality for SC EEPs. METHODS: A metaanalysis of case reports of SC EEPs, including the current case, was conducted. Also all available case reports of EEPs, without age limit, were analyzed to determine the distribution of EEPs localization. RESULTS: EEPs usually are found in teratoma localizations such as the SC area, ovary, paraovarian structures, and medastinum. The distribution of EEPs localization differs with age. Local recurrence rate of EEPs after coccyx excision is zero, however, it increases to 71% when the coccyx was left behind. CONCLUSION: The identical clinical characteristics of the SC teratomas and EEPs imply that the SC EEPs may be monophasic teratomas as their ovarian counterparts are named. Coccyx excision is an important part of the surgical treatment of these tumors, with an apparent decrease in the recurrence rate.  相似文献   
97.
目的 研究慢性阻塞性肺疾病(COPD)急性发作(AECOPD)时血清α-羟丁酸脱氢酶(α—HBDH)的变化及其与病情的关系。方法 测定66例AECOPD患者血清α—HBDH及其动脉血气分析,并且与59例COPD稳定期患者和34例健康对照者进行比较;研究血清α—HBDH变化与动脉血气分析指标之间的关系。结果 AECOPD组患者血清α—HBDH明显高于健康对照组和稳定期CODP患者组;血清α—HBDH与动脉血pH值和动脉血氧分压(PaO2)呈显著的负相关,相关系数分别是r=-0.654(P〈0.01),r=-0.401(P〈0.01);血清α—HBDH与动脉血二氧化碳分压(PaCO2)呈显著的正相关,相关系数r=0.422(P〈0.01)。结论 AECOPD时血清α—HBDH明显升高;血清α-HBDH升高可能与AECOPD患者病情的严重程度有关。  相似文献   
98.
“生命诚可贵,患者价更高,若为创收故,两者皆可抛”,近年来,医疗卫生行业不乏新闻,遗憾的是其中丑闻居多,比如最近这一出。“大部分医院都有倒卖病人的现象,有的倒出去,有的倒进来,医生从中收取少则50元,多则数千上万元的‘转院费’。当然,接受病人的医院,会采取种种方式尽量获得更多的医疗费:接受病人的医生,也将获得相应的奖金和提成……”近日,南京某三级医院一位外科医生曝出黑幕,“倒卖病人”由此进入公众视野,为不甘寂寞的医疗卫生领域又添新丑闻。这位医生同时反戈一击,向患者支招:看病千万别透露出有钱,不能爽快地告诉医生尽管用好药、用好设备。千万不能  相似文献   
99.
In this article, we report two siblings who have familial cerebellar ataxia and hypogonadism associated with sensorimotor axonal polyneuropathy documented by light microscopy. This combination has not been reported previously in the literature. Cerebellar ataxia and hypogonadism is reviewed according to the clinical and laboratory features of the reported cases in the literature.  相似文献   
100.
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