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OBJECTIVES: Brain edema occurs following clinical as well as experimental cardiac arrest (CA) and predicts a poor neurologic outcome. The objective of this study was to determine the expression of cerebral cortex aquaporin (AQP)-4, a member of a family of membrane water-channel proteins, in brain edema formation following normothermic or hypothermic CA. METHODS: Twenty-four rats were subjected to time-matched normothermic (N-Sham, 37.5 degrees C +/- 0.5 degrees C, n = 6) or hypothermic (H-Sham, 34 degrees C +/- 0.5 degrees C, n = 6) sham experiments and normothermic (N-CA, n = 6) or hypothermic (H-CA, n = 6) CA induced by asphyxiation for 8 minutes. Hypothermia was induced before CA. The animals were resuscitated with cardiopulmonary resuscitation, ventilation, and epinephrine administration. Brain edema was determined by brain wet-to-dry weight ratio at one hour of resuscitation. AQP4 immunoactivity in the cerebral cortex was determined using immunohistochemical staining and was semiquantified as an intensity of staining with an automated cell imaging system. RESULTS: Mild hypothermia in the sham experiments did not alter cerebral cortex AQP4 immunoactivity (mean +/- SD) (55.0 +/- 3.7 in H-Sham vs. 53.3 +/- 1.7 in N-Sham, p > 0.05). N-CA resulted in a significant increase in AQP4 immunoactivity (61.8 +/- 4.5) compared with N-Sham (p = 0.01) and H-Sham (p = 0.03). H-CA attenuated AQP4 compared with N-CA (53.4 +/- 1.3, p = 0.01). Brain wet-to-dry weight ratios were 4.41 +/- 0.07 in N-Sham, 4.40 +/- 0.08 in H-Sham (p > 0.05 vs. N-Sham), 4.55 +/- 0.04 in N-CA (p = 0.004 vs. N-Sham; p = 0.005 vs. H-Sham), and 4.43 +/- 0.09 in H-CA (p = 0.02 vs. N-CA; p > 0.05 vs. N-Sham and H-Sham). CONCLUSIONS: Cerebral cortical AQP4 expression is up-regulated after normothermic CA, which is attenuated by hypothermia induced before CA.  相似文献   
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OBJECTIVE: To evaluate the possibility and reliability of the hyoid-sternohyoid graft transfer in the correction of server subglottic laryngotracheal stenosis, and delineate the operation skills and clinical results. METHODS: Seven patients with severe subglottic stenosis underwent laryngotracheal reconstruction using the hyoid grafts with sternohyoid muscle flaps (HG-SHMF). Five of these patients had traumatic subglottic stenosis, one with scar tissue of unknown etiology arising in the subglottic region, another with tracheal narrowing caused by inhalation of hydrochloric acid. RESULTS: All seven patients were successfully decannulated with moderate good voice. The average time from reconstruction to decannulation was 15.4 months. The stent was endoscopically removed with a range of 3 to 22 months; the mean time required for stenting was 9.6 months. Two patients who received additional salvage reconstruction procedures because of graft or stent displacement were extubated with improved voices and satisfactory airway. CONCLUSIONS: The HG-SHMF transfer was a single-stage reconstruction, relatively simple procedure that can restore an adequate airway and a good voice. Patients undergoing laryngotracheal reconstruction with HG-SHMF must have regular, long-term follow-up since graft displacement and recurrent granulation tissue or scar reformation can cause restenosis after an initially successful surgery. This procedure should be used in a large number of patients to further test its reliability.  相似文献   
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通过大量循经疼痛病例观察,认为循经疼痛与经循线上的损伤、大脑皮层机能、植物神经机能状态、植物神经末梢结构的特殊联系有关。提出探求循经疼痛的病因对研究牵涉痛与经络的关系、防止手术损伤经络、治疗某些顽固性疼痛有重要意义。  相似文献   
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报告37例主动脉窦瘤破裂手术治疗结果。着重介绍手术方法,主张采用主动脉根部和窦瘤破入心腔的双切口,切除、修补窦瘤的同时矫正合并畸形。伴主动脉瓣膜垂致中度关闭不全者,主张行主动脉瓣替换术。术后早期死亡1例,余35例随访6个月-14年,心功能恢复良好。  相似文献   
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A型肉毒杆菌毒素治疗麻痹性斜视   总被引:2,自引:0,他引:2  
采用眼外肌注射A型肉毒杆菌毒素的方法,治疗17例(18只眼)麻痹性内斜视患者。最大的肌肉麻痹作用发生于注射后7~14天,最大斜视矫正度为50-,随访时间为4~20周,5例最终获得双眼视。未见全身副作用。认为,这种疗法可在部分患卉中替代斜视矫正术。  相似文献   
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目的评价米非司酮用于保守治疗异位妊娠的疗效。方法所选病例均住院治疗,予口服米非司酮50mg,每天两次,连服6天,定期复查B超和测定血p—HCG水平以观察疗效。结果68例异位妊娠患者的治疗,治愈46例,治愈率67.7%。结论米非司酮保守治疗异位妊娠疗效确切,副作用小。  相似文献   
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We studied the hemodynamic effects of using natural surfactant in premature baboons with hyaline membrane disease (HMD). Study animals (n = 5) received a single dose of surfactant immediately after delivery and control animals (n = 8) did not. Using microspheres at 3, 8, and 23 h we found no significant differences in left ventricular output, effective systemic flow, systemic-to-pulmonary patent ductus arteriosus (PDA) shunting, or in cerebral or renal organ blood flow. However, both groups had large PDA shunts (fraction of LVO to lungs greater than 0.40-0.55 at 3 and 8 h) resulting in low systemic perfusion (less than 80 ml/min/kg). Single dose surfactant did not improve the myocardial dysfunction and low cerebral and renal blood flow which occur during treatment for HMD.  相似文献   
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