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91.
92.
刺果甘草化学成分的研究   总被引:5,自引:0,他引:5  
从刺果甘草(Glycyrrhiza pallidiflora Maxim)的根和根茎中分离到五种化合物,经理化性质和光谱方法鉴定,化合物P-2为4-羟基-2,4’-二甲氧基查尔酮,为一新的化合物,命名为刺果甘草查尔酮(glypallichalcone,P-2)。其它分别为4'-O-methyl-coumestrol(P-1),谷氨酸乙酰化物(N-acetylglutamicacid,P-3)和芒柄花素(formononetin,P-4),均为首次从该植物中获得。此外还得到β-谷甾醇(β-sitos-terol,P-5)  相似文献   
93.
Aims. Multimodal coregistration uses multiple image datasets coregistered to an anatomical reference (i.e. MRI), allowing multiple studies to be viewed together. Commonly used in intractable epilepsy evaluation and generally accepted to improve localization of the epileptogenic zone, data showing that coregistration improves outcome is lacking. We compared seizure freedom following epilepsy surgery in paediatric patients, evaluated before and after the use of coregistration protocols at our centre, to determine whether this correlated with a change in outcome. Methods. We included paediatric epilepsy surgery patients with at least one anatomical and one functional neuroimaging study as part of their presurgical evaluation. Preoperatively designated palliative procedures and repeat surgeries were excluded. Multiple pre‐, peri‐, and postoperative variables were compared between groups with the primary outcome of seizure freedom. Results. In total, 115 were included with an average age of 10.63 years (0.12–20.7). All evaluations included video‐EEG (VEEG) and MRI. Seven (6%) had subtraction single‐photon emission CT (SPECT), 46 (40%) had positron emission tomography (PET), and 62 (54%) had both as part of their evaluation. Sixty (52%) had extratemporal epilepsy and 25 (22%) were MRI‐negative. Sixty‐eight (59%) had coregistration. Coregistered patients were less likely to undergo invasive EEG monitoring (p=0.045) and were more likely to have seizure freedom at one (p=0.034) and two years (p<0.001) post‐operatively. A logistic regression accounting for multiple covariates supported an association between the use of coregistration and favourable post‐surgical outcome. Conclusions. Coregistered imaging contributes to favourable postoperative seizure reduction compared to visual analysis of individual modalities. Imaging coregistration is associated with improved outcome, independent of other variables after surgery. Coregistered imaging may reduce the need for invasive EEG monitoring, likely due to improved confidence in presurgical localization. These findings support the use of multimodal coregistered imaging as part of the presurgical assessment in patients evaluated for surgical treatment of intractable epilepsy.  相似文献   
94.
The purpose of this study was to evaluate how cerebral blood flow and bolus arrival time (BAT) measures derived from arterial spin labeling (ASL) MRI data change for different hypercarbic gas stimuli. Pseudocontinuous ASL (pCASL) was applied (3.0T; spatial resolution=4 × 4 × 7 mm3; repetition time/echo time (TR/TE)=3,600/11 ms) sequentially in healthy volunteers (n=12; age=30±4 years) for separate experiments in which (i) normocarbic normoxia (i.e., room air), hypercarbic normoxia (i.e., 5% CO2/21% O2/74% N2), and hypercarbic hyperoxia (i.e., carbogen: 5% CO2/95% O2) gas was administered (12 L/minute). Cerebral blood flow and BAT changes were quantified using models that account for macrovascular signal and partial volume effects in all gray matter and regionally in cerebellar, temporal, occipital, frontal, and parietal lobes. Regional reductions in BAT of 4.6% to 7.7% and 3.3% to 6.6% were found in response to hypercarbic normoxia and hypercarbic hyperoxia, respectively. Cerebral blood flow increased by 8.2% to 27.8% and 3.5% to 19.8% for hypercarbic normoxia and hypercarbic hyperoxia, respectively. These findings indicate that changes in BAT values may bias functional ASL data and thus should be considered when choosing appropriate experimental parameters in calibrated functional magnetic resonance imaging or ASL cerebrovascular reactivity experiments that use hypercarbic gas stimuli.  相似文献   
95.
Cytosolic phospholipase A2 alpha (cPLA2 alpha) is the rate-limiting enzyme for release of arachidonic acid, which is converted primarily to prostaglandins via the cyclooxygenase (COX) 1/2 pathways, and leukotrienes via the 5-lipoxygenase (LO) pathway. We utilized inhibitors of cPLA2 alpha, COX-1/2 and 5-LO to determine the potential roles of these enzymes in development of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Blocking cPLA2 alpha prevented EAE development and greatly reduced antigen-induced production of Th1-type cytokines and IL-17. Blocking COX-1/2 delayed onset and reduced severity of EAE, and reduced production of Th1-type cytokines, but not IL-17. Blocking 5-LO delayed onset and reduced cumulative severity of EAE, but did not reduce production of Th1-type cytokines or IL-17. Finally, blockade of cPLA2 alpha from the onset of clinical EAE reduced duration of EAE relapses. Therefore, cPLA2 alpha represents a potential therapeutic target for treatment of MS.  相似文献   
96.
目的测定甘肃产五加中剌五加苷B、苷E的含量。方法高效液相色谱法,ODSKromasal柱。水乙晴(955)为流动相,检测波长222nm,柱温度25℃。结果本文可同时测定剌五加苷B、苷E的含量。剌五加苷B、苷E分别在0.064~0.320μg/ml;0.074~0.370μg/ml范围内峰面积与浓度呈线性关系,平均回收率分别为102.5%,RSD=4.2%,95.5%,RSD=4.6%。结论剌五加苷B、苷E在红毛五加中含量最高;茎皮中含量最高;剌五加苷E的含量高于苷B。  相似文献   
97.
OBJECTIVE: To examine the effects of bupropion sustained release (SR) and sertraline on anxiety in outpatients with recurrent DSM-IV-defined major depressive disorder. METHOD: This retrospective analysis was conducted using pooled data from 2 identical, 8-week, acute-phase, double-blind, placebo-controlled, parallel-group studies of bupropion SR (N = 234), sertraline (N = 225), and placebo (N = 233). Symptoms of anxiety and depression were measured using the 14-item Hamilton Rating Scale for Anxiety (HAM-A) and the 21-item Hamilton Rating Scale for Depression (HAM-D-21), respectively. Percentage reduction in baseline HAM-A total score for each treatment week was calculated to determine whether the time to onset of anxiolytic activity differed among antidepressant responders to each agent. Central nervous system (CNS) adverse events were tabulated. RESULTS: Bupropion SR and sertraline were comparably effective, both were superior to placebo in reducing depressive symptoms. and they did not differ in their effect on anxiety symptoms. Antidepressant responders (> 50% reduction in baseline HAM-D-21 score) in both groups showed marked and comparable reductions in HAM-A scores (baseline to exit). There were no differences between bupropion SR and sertraline in the median time (4 weeks) to reach a clinically significant anxiolytic effect (> or = 50% reduction in baseline HAM-A score). CNS adverse events were comparable for bupropion SR and sertraline, except for somnolence, which was more common in sertraline-treated patients. CONCLUSION: Bupropion SR and sertraline had comparable antidepressant and anxiolytic effects and an equally rapid onset of clinically significant anxiolytic activity. There was no difference in the activating effects between the 2 antidepressants. Selection between these 2 agents cannot be based on either anticipation of differential anxiolytic activity or differential CNS side effect profiles.  相似文献   
98.
99.
Brain tumors are the second most common malignancy of childhood after acute lymphocytic leukemia. Improvements in therapy have led to increased survival. It is estimated that by the year 2000 there will be approximately 200,000 survivors of childhood cancer. A proportion of these will have survived a central nervous system malignancy. As more children survive, complications of treatment are increasingly recognized. This paper reviews the spectrum of radiation-induced complications, both short- and long-term. Their frequency and characteristics will be reviewed as well as suggestions made to decrease their incidence.  相似文献   
100.
The application of real-time ultrasound imaging during surgical procedures   总被引:5,自引:0,他引:5  
Operative ultrasound using real-time high resolution B-mode ultrasound scanning is a practical and useful diagnostic aid. At operations upon the biliary tract, pancreas and blood vessels, ultrasound had a favorable impact upon surgical management. When similar operative roentgenographic studies were available, operative ultrasound compared favorably with both operative cholangiography and arteriography. Problems with the lack of familiarity of the surgeon with the performance and interpretation of imaging ultrasound and lack of specifically dedicated ultrasound instruments need to be resolved to increase and improve the use of this potentially helpful aid to surgical diagnosis during operation.  相似文献   
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