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71.
72.
BACKGROUND: Tumour necrosis factor-alpha (TNF-alpha) is an important regulator of the chronic inflammation contributing to tumour progression. Infliximab, an anti-TNF-alpha monoclonal antibody was investigated in this trial of patients with advanced cancer. The primary objectives were to determine the safety profile and biological response of infliximab in a cancer population. Clinical response was a secondary objective. PATIENTS AND METHODS: Forty-one patients received infliximab at 5 mg/kg (n = 21) or 10 mg/kg (n = 20) i.v. at 0 and 2 weeks and then every 4 weeks. Post-treatment samples were measured for changes in plasma and serum TNF-alpha, CCL2, IL-6 and C-reactive protein (CRP). RESULTS: Infliximab was well tolerated with no dose-limiting toxic effects. At both doses of infliximab, neutralisation of serum TNF-alpha was observed after 1 h while plasma CCL2, IL-6 and serum CRP were decreased 24 and 48 h following infliximab administration. Seven patients experienced disease stablisation (range 10-50+ weeks). There was no evidence of disease acceleration in any patient. CONCLUSIONS: Infliximab treatment was safe and well tolerated in patients with advanced cancer. There was evidence of biological activity with baseline TNF-alpha and CCL2 being correlated with infliximab response.  相似文献   
73.
实验动物资源是国家生命科学研究的重要科技资源。实验动物资源的共享和充分利用是生物科技创新的基础和保障。有效的共享机制和合理的共享方式是实现实验动物资源共享和充分利用的重要保障,是规范实验动物资源共享行为和确保共享安全的迫切需要。  相似文献   
74.
This randomized controlled trial was designed to answer the question: does administration of dexamethasone to neonates with bronchopulmonary dysplasia decrease the need for assisted ventilation? Twenty-five infants with a birth weight < 1501 g, requiring mechanical ventilation and FiO2 of ± 0.30 at 21-35 days of age, were randomized to treatment with iv dexamethasone or to sham injections for 12 days. The primary outcome criterion was extubation within seven days after study entry. Treatment (n= 12) and control (n= 13) groups were well matched at entry. Dexamethasone facilitated weaning from assisted ventilation (p= 0.0154). There was no increased incidence of infection. Dexamethasone treatment resulted in a significant increase in glucosuria (p= 0.0002) and in systolic blood pressure (p= 0.0034). There was a significant decrease in heart rate (p= 0.0001) and a significant weight loss (p= 0.0002) following dexamethasone treatment. Dexamethasone treatment facilitated weaning from assisted ventilation but several systemic effects were noted that deserve further evaluation before dexamethasone becomes routine treatment.  相似文献   
75.
The effects of intermittent positive airway and continuous negative extrathoracic pressure ventilation on cerebral blood volume in preterm infants were studied using near infrared spectroscopy. In 12 infants continuous negative extrathoracic pressure caused a median decrease in cerebral blood volume of 0.14ml/100ml brain (95% confidence intervals (CI) 0.035–0.280) compared with no respiratory support. Oxygenated and deoxygenated haemoglobin also decreased, implying increased venous drainage as the main effect. In 17 infants intermittent positive pressure ventilation also caused a median reduction in cerebral blood volume of 0.06 ml/100 ml brain (95% CI 0.010–0.115) compared with endotracheal positive airway pressure. Deoxygenated haemoglobin increased by 0.07 ml/100 ml brain (95% CI 0.010–0.100) while oxygenated haemoglobin decreased by O.lOml/lOOml brain (95% CI 0.005–0.175). The increase in deoxygenated haemoglobin implies decreased venous drainage and the decrease in oxygenated haemoglobin implies that other factors may also be significant. Heart rate, blood pressure and oxygen saturation were monitored continuously and remained stable.  相似文献   
76.
To compare the prostate volumes defined on magnetic resonance imaging (MRI), and noncontrast computerized tomographic (CT) scans used for three-dimensional (3D) treatment planning.

: Ten patients simulated for treatment using immobilization and a retrograde urethrogram. 3D images were used to compare prostate volumes defined by MRI (4–6 mm thick slices) and CT images (5 mm thick slices). Prostate volumes were calculated in cm3 using the Scanditronix 3D planning system. MRI/CT images were merged using bony anatomy to define the regions of discrepancy om prostate volumes.

: The mean prostate volume was 32% larger (range −5–63%) when defined by noncontrast CT compared to MRI. The areas of nonagreement tended to occur in four distinct regions of discrepancy: (a) the posterior portion of the prostate, (b) the posterior-inferior-apical portion of the prostate, (c) the apex due to diasgreement between a urothrogram based definition and the location defined by MRL, (d) regions corresponding to the neurovascular bundle.

: There is a tendency to overestimate the prostate volume by noncontrast CT compared to MRI. Awareness of this tendency should allow us to be to more accurately define the prostate during 3-D treatment planning.  相似文献   

77.
Time related neutralization of two doses acetyl salicylic acid   总被引:3,自引:0,他引:3  
Aspirin has a well established role in the prevention of arterial thrombosis. Discussion on the efficacy and safety of aspirin in the treatment and prophylaxis of thrombosis has become an important issue. In fact, hemorrhage complications are often associated with its use. On the other hand, previous studies showed unexpected thrombotic potencies associated with the presence of this drug at ultra low doses (ULD) in the circulation. In this study, we aimed to evaluate the effect of aspirin at ULD, injected 1, 2, or 3 hours after the administration of aspirin at 100 mg/kg, on hemostasis and bleeding in rats. We used an experimental model of thrombosis induced by laser beams to evaluate these effects. Platelet aggregation was determined by Cardinal and Flower method. Results from this investigation demonstrate that the neutralizing effect of aspirin at ULD did not operate significantly 1 hour after the injection of aspirin at 100 mg/kg. This effect was observed 2 and 3 hours after. The use of aspirin at ULD to neutralize the side effects of aspirin at high doses will reduce the hemorrhagic risk during extra corporeal circulation. The therapeutic benefit and safety of aspirin therapy in the treatment of cardiovascular diseases can be obtained.  相似文献   
78.
目的:通过对突发性聋病人血中一氧化氮(NO)、丙二醛(MDA)、超氧化物歧化酶(SOD)含量的检洲,探讨突聋与血氧自由基和自由基的清除剂SOD之间的关系。方法:采用硝酸还原酶法测定了30例突聋病人血中NO含量,并以25例同期体检正常的健康人为对照组;同时还用硫代巴比妥酸比色法测定MDA含量,用黄嘌呤氧化酶法测定SOD含量。砖呆;应用金纳多、能量合剂、克林臭(即马来酸桂哌齐特,钙通道阻滞药)联合静脉输入,突聋各组的听力均有不同程度提高,有效率在78.57%以上。治疗后同对照组相比,血清NO、MDA水平明显低于患病之初,而SOD活性明显高于治疗之前,P〈0.01。结论;检测突聋病人血中N0、MDA、SOD的含量,能帮助我们探讨突聋的发病机理,估计预后。血氧自由基的升高可能是突聋发病因素之一,而SOD的含量可以帮助我们估计预后。  相似文献   
79.
Primary osteogenic sarcoma of the skull is an exceedingly rare condition. An adult male patient is described, who had a painless swelling in the right forehead that had rapidly enlarged in the previous 6 months. Radiological investigations showed a large destructive mass lesion involving the right side of the frontal bone with extension into the frontal sinus, causing marked extradural compression of brain parenchyma. Histopathological examination confirmed the lesion to be primary osteogenic sarcoma.  相似文献   
80.
目的研究全反式维甲酸(ATRA)及联合应用神经营养因子(BDNF,GDNF)对体外培养的神经干细胞(NSCs)分化的影响。方法取新生SD大鼠的前脑室下带(SVZ)区,按NSCs的常规培养方法分离、培养。用免疫细胞化学法鉴定巢蛋白(nestin)、微管相关蛋白-2(MAP-2)、胶质原纤维酸性蛋白(GFAP)的表达,以此来观察ATRA、BDNF、GDNF单独或联合应用对次代神经球细胞分化的作用。结果原代及次代神经球均显示nestin阳性,并可分化为MAP-2阳性神经元样细胞及GFAP阳性胶质细胞样细胞。1μmol/LATRA可促进NSCs分化为MAP-2阳性细胞的比例达(29.14&#177;5.00)%,显著高于对照组的(7.19&#177;1.21)%,差异有高度统计学意义(P〈0.001)。ATRA联合应用10ng/ml的BDNF或GDNF,与单独使用ATRA比较,并不显著提高NSCs分化为MAP-2阳性细胞的比例。结论ATRA可促进神经干细胞向神经元方向分化,ATRA联合应用BDNF或GDNF无明显的协同作用。  相似文献   
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