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101.
102.
银杏叶提取物对兔心肌缺血再灌注损伤时中性粒细胞活化的影响 总被引:11,自引:0,他引:11
目的 观察兔心肌缺血再灌注前后PMN(中性粒细胞)的活性变化过程。了解银杏叶提取物保护心肌是否与影响中性粒细胞活化作用有关。方法 取30只日本大耳白兔随机均分为3组,假手术对照组、缺血再灌注组和实验用药组。用药方法:用自制的银杏叶提取物注射剂(总黄酮含量5mg/ml)5ml静滴给药。分别于冠脉结扎前和结扎缺血1h后采血用布式显微镜观察白细胞活化状态的变化。检测白细胞表面粘附分子CD11/CD18表 相似文献
103.
We have compared the effects of an i.p. pretreatment with L-DOPA (200 mg/kg) associated with benserazide (25 mg/kg) on neurotoxic effects of either 6-hydroxydopamine (6-OHDA) (50 microg, 10 microl per mouse) or 1-methyl-4-phenylpyridinium (MPP+) (17.5 microg, 10 microl per mouse). The striatal dopamine (DA) content, the vesicular monoamine transporter (VMAT2) density, as well as the hypothalamic norepinephrine (NE) content were measured 8 days after treatments. The L-DOPA-benserazide pretreatment worsened by 65% the 6-OHDA-induced depletion in striatal DA. On the contrary, it reduced by 42% the MPP+-induced depletion in striatal DA and by 54% the MPP+-induced decrease in VMAT2 density. It was noticed that the L-DOPA-benserazide pretreatment did not modify the marked decrease in hypothalamic NE content induced by 6-OHDA. 相似文献
104.
Pretreatment of rats with the extract of Ginkgo biloba termed EGb761 reduced the behavioral sensitization induced by successive
-amphetamine administrations (0.5 mg/kg) as estimated by increasing values of locomotor activity. EGb761 pretreatment also prevented the reduced density of [3H]dexamethasone binding sites in the dentate gyrus and the CA1 hippocampal regions of
-amphetamine treated animals. These observations suggest that EGb761, by reducing glucocorticoid levels, could modulate the activity of the neuronal systems involved in the expression of the behavioral sensitization. 相似文献
105.
The augmentation effect of (–)pindolol as used in combination with SSRI to treat major depression has been ascribed to blocking
of dorsal raphe nucleus cell body 5-HT autoreceptors. In this study, the radioligand [carbonyl-11C]WAY-100635 and positron emission tomography were used to establish whether pindolol at a clinical dose level (10 mg s.o.d.)
occupies 5-HT1A receptors in the human brain in vivo. Three healthy males were recruited and each subject was used as his own control. The
5-HT1A receptor occupancy was calculated for the frontal and temporal cortex and the raphe nuclei, using and a ratio analysis with
the cerebellar cortex as the reference region. Maximal pindolol plasma concentration was reached within 3 h after drug administration.
Two hours after pindolol administration, the regional 5-HT1A receptor occupancy was within the range 7–21% in the three subjects. The study confirms that the 5-HT1A-receptor may be a clinically significant target for pindolol.
Received: 8 March 1999 / Final version: 15 March 1999 相似文献
106.
Pulak K. Chakraborty Thomas J. Mangner Diane C. Chugani Otto Muzik Harry T. Chugani 《Nuclear medicine and biology》1996,23(8):1005-1008
Alpha-[11C]methyl-l-tryptophan (AMT) has been synthesized by stereoselective methylation with [11C]methyl iodide of the lithium-enolate generated by treating dimethyl 2(S),3a(R),8a(S)-(+)-hexahydro-8(phenylsulfonyl) pyrrolo[2,3-b]indole-1,2-dicarboxylate (2) with lithium diisopropyl amide (LDA) at −55 °C, followed by ring opening using trifluoroacetic acid and alkaline hydrolysis of the protecting groups. The crude product was purified by a simple reverse-phase C-18 Sep-Pak procedure. The purified product was isolated with an average radiochemical yield of 53 ± 12% (decay corrected) in 30–35 min from [11C]methyl iodide. At end of synthesis (EOS), 138 ± 35 mCi (n = 24) of product was collected with a specific activity of ca. 1–1.3 Ci/μmol (EOS) (4–5 Ci/μmol @ EOB) starting from 1.5 Ci (EOB) of [11C]CO2. 相似文献
107.
The dehydrogenase form of 11 β-hydroxysteroid dehydrogenase (11-DH) which catalyzes the oxidation of the biologically active steroid, corticosterone, to its inactive metabolite, 11-dehydrocorticosterone, is found in rat brain. The distribution and localization of 11-DH-like labeling in the rat brain was examined by immunocytochemistry. 11-DH-like immunostaining was found in all subfields of the hippocampus and in many other parts of the brain, including the preoptic area (POA), central nucleus of the amygdala, bed nucleus of the stria terminalis (NIST) and the cerebral cortex. Percentages of 11-DH-positive cells ranged from 10% in the POA and NIST to 50% to 60% in the hippocampus. When combined with neuronal or glial markers, 11-DH-like immunostaining was found to be predominantly localized within neurons, ranging from 10% or less glial labeling in hippocampus, amgydala and cortex to 22% glial labeling in the POA and NIST. Immunostaining was present in both the cytoplasmic and nuclear components of some cells in addition to their projections. In the kidney, 11-DH has been postulated to be a key component in a mechanism by which aldosterone gains access to renal Type I receptors despite the presence of much higher concentrations of glucocorticoids. The present data is consistent with a similar mechanism occurring in at least some parts of the brain, although the hippocampus appears to be an important exception because it does not appear to be differentially responsive to aldosterone in spite of its high 11-DH activity and immunoreactivity. However, the hippocampus is not implicated in neural control of salt appetite and fluid balance, whereas some of the other brain regions like the POA, NIST and amygdala are believed to be involved. Other aspects of 11-DH localization must therefore be examined in future studies, including the co-presence of mineraiocorticoid receptors and 11-DH in the same or adjacent cells and the possible significance of the relatively high glial localization of 11-DH immunoreactivity in the POA and NIST. 相似文献
108.
重组人白细胞介素11生物学活性测定方法研究 总被引:2,自引:0,他引:2
目的建立重组人白细胞介素 11(rhIL 11)生物活性测定方法。方法运用单克隆方法筛选出rhIL 11敏感细胞株T 10 ,采用溴化四唑蓝比色法进行rhIL 11生物活性测定 ,采用四参数方程对测定结果进行计算。结果以世界卫生组织国际标准品作为参照品 ,与美国Genetics公司rhIL 11上市产品NeumegaTM进行测定比较 ,结果显示国内同类产品与其生物活性一致 ,RSD均小于 10 %。结论此方法可用于rhIL 11生物活性测定 相似文献
109.
目的 评价红霉素环11,12—碳酸酯治疗呼吸系统和皮肤细菌性感染的安全性与有效性。方法 采用多中心、区组随机化、双盲双模拟对照试验设计,选用罗红霉素作对照药。试验药:红霉家环ll,12—碳酸酯片剂,250~500mg/次,每日2次。对照药:罗红霉素片剂,150~300mg/次,每日2次,疗程均为5~10d。结果 实验组28例(呼吸系统感染17例,皮肤软组织感染ll例)与对照组29例(呼吸系统感染17例,皮肤软组织感染12例)临床总有效率分别为85.71%与82.76%,细菌清除率分别为76%与83.33%,细菌敏感百分率分别为89.36%与72.34%,不良反应发生率分别为12.1%与12.5%,两组比较无统计学差异。结论 红霉素环11,12—碳酸酯治疗细菌性感染安全有效。 相似文献
110.
红霉素环11,12-碳酸酯的体外抗菌活性研究 总被引:1,自引:0,他引:1
目的评 价红霉素环11,12-碳酸酯的体外抗菌活性。方法 采用琼脂平皿二倍稀释法测定国产和进口红霉素环11,12-碳酸酯对临床分离致病菌的体外抗菌作用,并与红霉素、罗红霉素、克拉霉素、地红霉素、阿奇霉素和乙酰螺旋霉素进行了比较。结果 国产和进口红霉素环11,12-碳酸酯对579株临床分离菌的抗菌活性相近,对革兰氏阳性菌和厌氧菌的抗菌活性比红霉素强2~8倍,优于罗红霉素、克拉霉素、地红霉索、阿奇霉素、乙酰螺旋霉素,但对革兰氏阴性菌的抗菌活性稍弱于阿奇霉素。红霉索环11,12-碳酸酯对金葡菌显示抑菌作用,对化脓链球菌在2~4倍MIC浓度时显示杀菌作用;红霉素环11,12-碳酸酯抗金葡菌和化脓链球菌的活性随着pH的增加而增强,接种量和血清浓度对国产红霉素环11,12-碳酸酯抗金葡菌和化脓链球菌的活性无明显影响。结论 红霉素环11,12-碳酸酯具有较强的体外抗菌活性,国产红霉素环11,12-碳酸酯抗菌活性与进口相近,优于红霉素、罗红霉素、克拉霉素、地红霉素、阿奇霉素和乙酰螺旋霉素。 相似文献