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91.

Background  

The role of basic fibroblast growth factor (bFGF) in chemoresistance is controversial; some studies showed a relationship between higher bFGF level and chemoresistance while other studies showed the opposite finding. The goal of the present study was to quantify bFGF levels in archived tumor tissues, and to determine its relationship with chemosensitivity.  相似文献   
92.
硝基甘油对狗缺血区冠脉循环的作用   总被引:1,自引:0,他引:1  
用实验性犬冠脉狭窄模型,冠脉内恒流灌注硝基甘油0.5μg/kg.min-1,使冠脉血流量(CBF)增加、远端小动脉压(DCP)、冠脉血管总阻力(RT)、小冠脉血管阻力(RS)及冠状静脉低切血粘(ηb)减少;而主动脉压和心率无明显变化。恒流灌注硝基甘油1μg/kg.min-1时,在开始5min内冠脉循环的变化同上,并伴大冠脉血管阻力(RL)减少,10 min后出现CBF减少和RT,RL及ηb增加。结果提示,硝基甘油有缓解和加重心肌缺血的双重作用,其作用可能与剂量张扩张远端小动脉压的程度有关。  相似文献   
93.
ABSTRACT. The pulsed Doppler principle enables us to study the bloodflow velocity at specific points in the heart and great vessels. In such aorto-pulmonary connections as patent dnctus arteriosus, aorto-pulmonary window and truncus arteriosus the bloodflow velocity patterns are typical of the malformation. Based on knowledge of these abnormal flow patterns the diagnoses of these malformations can be made.  相似文献   
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中国大陆地区妇女骨质疏松筛选工具探讨   总被引:3,自引:0,他引:3  
目的建立适用于中国大陆地区40岁及以上妇女的骨质疏松(osteoporosis,OP)筛选工具。方法以20~39岁妇女腰椎骨密度的均数和标准差作为参考值计算T—score。以双能X线骨密度仪(dual—energy X—ray absorptiometry,DxA)的测量结果作为金标准,采用二分类的Bayes判别分析,建立判别函数。结果我国大陆地区40岁及以上妇女OP筛选工具(osteoporosis screening tool for Chinese,OSTC)为:体重-2×年龄+50。判别准则为OSTC〉0为无OP危险性,OSTC≤0为有OP危险性。OSTC的正判率为75.78%,灵敏度为76.8%,特异度为75.1%,Kappa值为0.51(P=0.000),说明OSTC与DXA的判定结果一致性尚可。结论OSTC是一个简便的OP筛选工具。根据年龄、体重两个变量的简单计算,即可对我国大陆地区40岁及以上的妇女进行OP危险性的筛选。但OSTC没有得到外部数据的验证,其优劣还有待进一步评价。  相似文献   
97.
During venoarterial extracorporeal membrane oxygenation the right carotid artery is ligated in a hypoxic neonate. The aim of the present study was to compare the morphology and metabolism of the left and right basal ganglia in 10 neonates after extracorporeal membrane oxygenation, using proton magnetic resonance imaging and spectroscopy. Data could be obtained in 9 neonates. No significant metabolic differences were found between either the left or right basal ganglia, despite a small right-sided thalamic infarct in one child. Metabolism was normal in all cases. All the infants showed symmetrical neurodevelopment.

Conclusion: Ligation of the right carotid artery for venoarterial extracorporeal membrane oxygenation did not produce persistent changes in brain metabolism in the basal ganglia in this small group of patients.  相似文献   
98.
The polyol pathway plays an important role in the formation of diabetic complications of the eye. Due to variations in the pharmacokinetic properties of aldose reductase inhibitors and variations in the degradation of the blood-ocular barrier, it is often difficult to determine the proper intraocular levels of aldose reductase inhibitor required for inhibition of aldose reductase activity in ocular tissues. Utilizing localized magnetic resonance spectroscopy (MRS), the present method can determine adequate inhibition of aldose reductase activity in the lens by noninvasively measuring polyol pathway activity in the eye. New Zealand White rabbits, under anesthesia, were administered an intravitreal injection of 3-fluoro-3-deoxy-D-glucose (3FDG). Localized MRS was then used to assess polyol pathway activity by determining the levels of 3-fluoro-3-deoxy-D-sorbitol (3FS) and 3-fluoro-3-deoxy-D-fructose (3FF) metabolite formation from 3FDG in the eye. MRS was able to follow the loss of 3FDG from the vitreous into the anterior segment of the eye and particularly into the lens and aqueous. The primary metabolism of 3FDG observed by MRS was the formation of 3FS in the lens that is catalyzed by aldose reductase. Production of 3FS was linear in time and decreased with the oral administration of an aldose reductase inhibitor.  相似文献   
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C-reactive protein (CRP), a marker of inflammation, has been associated with cardiovascular disease. Risk of cardiovascular disease is increased in migraineurs with aura. Results from a clinical report, case–control and a cohort study suggest that CRP is elevated in migraineurs compared with non-migraineurs. We examined the proposed association in a case–control study nested within two large population-based studies. The relationship between migraine and CRP (high-sensitivity CRP) was studied in 5906 men and women aged 55.0 ± 8.5 years in the Reykjavik Study and 1345 men and women aged 27.7 ± 5.5 years from the Reykjavik Study for the Young. A modified version of the International Headache Society's criteria was used to categorize people into migraineurs (two or more symptoms) or non-migraineurs. Migraineurs with visual or sensory symptoms were further defined as having migraine with aura (MA) or without aura (MO). Multivariable-adjusted CRP levels were similar in migraineurs and non-migraineurs for men (0.83 vs. 0.79 mg/l, P  = 0.44) and for women (0.87 vs. 0.87 mg/l, P  = 0.90). When further stratified by migraine aura and age, no differences were found between non-migraineurs, MO and MA among men. In women, CRP levels were borderline higher in those with MO compared with non-migraineurs and those with MA (1.01 mg/l vs. 0.81 and 0.75 mg/l, P  = 0.08 and P  = 0.08) in age group 19–34 years, but significantly lower in age group 60–81 years (0.52 mg/l vs. 1.07 and 1.01 mg/l, P  = 0.007 and P  = 0.03). CRP levels were not increased among migraine sufferers compared with non-migraineurs. Older women migraineurs without aura had lower CRP values than non-migraineurs and migraineurs with aura.  相似文献   
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