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991.
用微量马桑内酯注入Wistar大鼠左侧前肢运动皮质,造成急性局灶型癫痫。用光镜、电镜和体视学方法研究其运动皮质第V层结构的改变。结果显示:癫痫大鼠运动皮质灶区、灶旁区的神经细胞数和胶质细胞数均分别比对照大鼠灶区和灶旁区显著减少;灶区神经毡中突触性终末数,显著减少;突触性终末的面积分数明显减少,而树突的面积分数无变化;神经胶质突起的面积分数增加。  相似文献   
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SUMMARY The interferons are natural glycoproteins secreted in response to various stimuli, including viral infection. They have antiviral, antiproliferative and immunomodulatory effects on different target cell populations. Since recombinant human interferons have become available, they have been tested in a wide range of malignancies. They are well established in the treatment of hairy cell leukaemia, chronic myelogenous leukaemia and multiple myeloma. Although they have documented activity against lymphoma, melanoma, renal cell cancer and carcinoid tumours, their role in the treatment of these tumours is less clear. In the common solid tumours, such as lung cancer and colorectal cancer, the use of interferons remains experimental. Here we will summarise their practice applications in oncology, using randomised studies where available to establish their place in multi-modality treatment. We will not discuss their use as antiviral or immunomodulating agents in viral and autoimmune diseases, multiple sclerosis or after organ transplantation.  相似文献   
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Background. Heparin bonding of the cardiopulmonary bypass (CPB) circuit may be associated with a reduced inflammatory response and improved clinical outcome. The relative contribution of a heparin-bonded oxygenator (ie, >80% of circuit surface area) to these effects was assessed in a group of pediatric patients.

Methods. Twenty-one pediatric patients undergoing CPB operations were assigned randomly to receive either a heparin-bonded oxygenator (group H, n = 11) or a nonbonded oxygenator (group C, n = 10) in otherwise nonbonded circuits. The two groups were similar in pathology, age, weight, CPB time, and cross-clamp time. Plasma levels of the cytokines tumor necrosis factor-, interleukin-6, and interleukin-8, as well as terminal complement complex, neutrophils, and elastase, were analyzed before, during, and after CPB.

Results. Significant levels of tumor necrosis factor- were not detected in either group. Plasma levels of all other markers increased during and after CPB compared with baseline. Plasma levels of interleukin-6 peaked in both groups 2 hours after the administration of protamine but remained significantly higher in group C 24 hours after operation. Plasma concentrations of interleukin-8 peaked at similar levels in both groups 30 minutes after protamine administration and returned to baseline thereafter. Levels of terminal complement complex and elastase peaked in both groups 30 minutes after protamine administration. Plasma levels of terminal complement complex were significantly higher at the end of CPB and after protamine administration in group C. Elastase levels were significantly higher 2 and 24 hours after CPB in group C. The ventilation time of patients in group H was significantly lower than that of patients in group C: 10 (range, 3 to 24) versus 22 (range, 7 to 24) hours, respectively (p < 0.01).

Conclusions. The present study confirms the proinflammatory nature of pediatric operations and demonstrates a lessened systemic inflammatory response with the use of heparin-bonded oxygenators. This is achieved without bonding of the entire circuit, which could have significant cost-benefit implications by negating the need for custom-built heparin-bonded circuitry.  相似文献   

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Two cases of very difficult weaning from cardiopulmonary bypass after cardiac surgery in children with pulmonary hypertension and ventricular dysfunction are reported. Children fail to respond to conventional therapy combining nitrovasodilators and inotropic support and react successfully to combined inhaled nitric oxide (NO) and epinephrine or left atrial infused norepinephrine. Postoperative NO inhalation must be prolonged and no toxicity appears. Pulmonary endothelial function recovers only after several days.  相似文献   
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Background: We analyzed morbidity and mortality, sites of recurrence, and possible prognostic factors in 95 (78 male, 17 female) patients with MPM on phase I–III trials since 1990. A debulking resection to a requisite, residual tumor thickness of ≤ 5 mm was required for inclusion. Methods: Preoperative tumor volumes were determined by three-dimensional reconstruction of chest computerized tomograms. Pleurectomy (n=39) or extrapleural pneumonectomy (EPP; n=39) was performed. Seventeen patients could not be debulked. Preoperative EPP platelet counts (404,000) and mean tumor volume (491 cm3) were greater than that seen for pleurectomy (344,000, 114 cm3). Results: Median survival for all patients was 11.2 months, with that for pleurectomy 14.5 months, that for EPP 9.4 months, and that for unresectable patients 5.0 months. Arrhythmia (n=14; 15%) was the most common complication, and there were two deaths related to surgery (2.0%). Tumor volume of >100 ml, biphasic histology, male sex, and elevated platelet count were associated with decreased survival (p<0.05). Both EPP and pleurectomy had equivalent recurrence rates (27 of 39 [69%] and 31 of 39 [79%], respectively); however, 17 of 27 EPP recurrences as opposed to 28 of 31 pleurectomy recurrences were locoregional (p2=0.013). Conclusions: Debulking resections for MPM can be performed with low operative mortality. Size and platelet count are important preoperative prognostic parameters for MPM. Patients with poor prognostic indicators should probably enter nonsurgical, innovative trials where toxicity or response to therapy can be evaluated. Presented at the 49th Annual Cancer Symposium of The Society of Surgical Oncology, Atlanta, Georgia, March 21–24, 1996.  相似文献   
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