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目的观测小鼠脑梗塞周围扩散性去极化(PIDs)的内源光信号变化特征,探索胶质纤维酸性蛋白(GFAP)和波形蛋白
(Vim)基因敲除对PIDs的影响。方法以GFAP和Vim基因敲除(GFAP-/-Vim-/-)小鼠及其野生型(GFAP+/+Vim+/+)小鼠为研究对
象,线栓法制备大脑中动脉梗塞(MCAO)模型,应用四波长内源光信号(OIS)成像技术监测两组动物4 h内PIDs的发作情况。
结果OIS成像显示PIDs在空间分布上表现为连续的、红蓝相间的弧形波,由发源处向四周缓慢播散;PIDs存在5种不同空间播
散类型:喙-尾播散类型、侧方-内侧播散类型、尾-喙播散类型、对侧播散类型和内侧-侧方播散类型。GFAP-/-Vim-/-小鼠和GFAP+/+
Vim+/+小鼠PIDs的发作次数、播散类型、速度及时程组间比较无统计学差异(P>0.05)。结论四波长OIS成像技术可获得PIDs
的高分辨率彩色影像,为更深入研究PIDs的时空特性创造了条件;GFAP和Vim基因敲除对MCAO模型制备后4 h内PIDs的发
作无显著影响。
  相似文献   
85.
动脉粥样硬化(atheroscIerosis,AS)是导致心脑血管事件发生的关键因素,为多种心脑血管疾病共同的病理生理基础.其证候、病机等属于中医理论的"血瘀证".而三七自古便是历代医家常用的活血化瘀之要药.综述近年来三七在治疗动脉粥样硬化方面的研究进展.  相似文献   
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Aim: To carry out a pilot study to investigate the effect of short‐term oral probiotic administration on the metabolism of sulfasalazine (SSZ) in patients with rheumatoid arthritis (RA) stabilized on SSZ. Methods: Twelve subjects with RA taking stable doses of SSZ for a minimum of 3 months prior to the study, received a probiotic preparation contained three strains of bacteria (1.8 × 109 CFU/day) twice daily for 1 week. Single point blood and 12‐h urine samples were taken before and after probiotic treatment and 3 weeks following discontinuation of probiotics, for determination of SSZ and its metabolites. The presence of the probiotic bacteria in the feces of patients was investigated by denaturing gradient gel electrophoresis (DGGE). Results: Adverse events recorded were three instances of gastrointestinal disturbance and one flare of RA. Plasma and urinary levels of SSZ and its metabolites showed no statistically significant changes after probiotic administration and the incidence of gastrointestinal disturbance did not appear to be ascribed to higher sulfapyridine plasma levels. Probiotic‐specific DGGE bands were detected in the feces of some patients after the treatment period. Conclusions: Short‐term treatment of RA patients with a multi‐strain probiotic did not significantly influence SSZ metabolism as has been demonstrated in animal models.  相似文献   
87.
1. The in vitro metabolism of the new insecticide flupyrazofos was studied using rat liver microsomes. Two metabolites were produced and identified as O, O -diethyl O -(1- phenyl-3-trifluoromethyl-5-pyrazoyl) phosphoric acid ester (flupyrazofos oxon) and 1- phenyl-3-trifluoromethyl-5-hydroxypyrazole (PTMHP) based on UV and mass spectral analysis. 2. Cytochrome P450 oxidatively converted flupyrazofos to flupyrazofos oxon, a major metabolite and phenobarbital-induced microsomes increased this desulphuration by 8- fold. 3. Flupyrazofos oxon was converted to PTMHP with a half-life of 47 8?min by chemical hydrolysis and this conversion also proceeded non-enzymatically under our microsomal incubation conditions.  相似文献   
88.
Background: The aim of this study was to evaluate the efficacy of ondansetron and ramosetron in the reduction of post‐operative nausea and vomiting (PONV) associated with patient‐controlled analgesia (PCA) after cardiac surgery. Methods: A total of 320 patients scheduled for elective cardiac surgery were enrolled. Patients were randomly assigned to one of four treatment regimens (n=80 in each group): no prophylactic antiemetics (group P); intravenous (i.v.) ondansetron 4 mg at the end of surgery and 12 mg added to PCA (group O); i.v. ramosetron 0.3 mg at the end of surgery and no antiemetics added to PCA (group R1); and i.v. ramosetron 0.3 mg at the end of surgery and 0.6 mg added to PCA (group R2). Results: The incidence of PONV during the 48‐h post‐operative period was lower in groups O (46%), R1 (54%), and R2 (35%) compared with group P (71%, P<0.001). The incidence and severity of nausea were lower in groups O, R1, and R2 than in group P during the 24‐h post‐operative period, whereas the incidence and severity of nausea during 24–48 h after surgery were lower in groups O and R2, but not in group R1, than in group P. Compared with group P (53%), the frequency of rescue antiemetic usage was significantly lower in groups O (34%) and R2 (29%), but not in group R1 (43%). Conclusion: The addition of either ondansetron or ramosetron to PCA can reduce the incidence of PONV during 48 h after cardiac surgery.  相似文献   
89.
Objective To examine the relationship of single-nucleotide polymorphisms(SNPs)in candidate genes with the lipid responses to simvastatin.Methods Chinese patients were treated with simvastatin 40 mg daily for at least 6 weeks.20 SNPs in 11 genes were genotyped.Results 95 patients age(mean±SD)57.5±10.6 years completed the treatment.The Adiponectin 45T>G polymorphism was significantly related to absolute reductions in total cholesterol(TC)and LDL-cholesterol with a trend(P=0.053)for percentage reductions in TC(TT∶TG∶GG=-38.4%∶-35.6%∶-32.6%).Similar findings were seen with LDL-Receptor(LDLR)SNPs(2052T>C and 1866C>T)with absolute reductions in TC and LDL-cholesterol significantly associated.The Breast Cancer Resistance Protein(ABCG2)421C>A polymorphism was related(P<0.05)to HDL-cholesterol response(CC∶CA∶AA=+0.50%∶-5.73%∶-11.41%).Conclusions Adiponectin,LDLR and ABCG2 SNPs had some influence on the lipid responses to simvastatin.  相似文献   
90.
目的研究0.5%心居康杀白蚁饵剂对台湾乳白蚁(Coptotermes formosanusShiraki)的防治效果。方法2001年在无锡和杭州进行了试验研究,试验分实验室和建筑物现场试验两个部分进行。结果无论是地上(AG)投药,还是地下(IG)投药,不论是室外投药还是室内投药,消灭一个族群需要35~69 d,平均(54.75±12.25)d。消灭一个族群只需要0.5%心居康杀白蚁饵剂48~150 g,平均(103.05±28.9)g,折合有效成分(0.52±0.146)g。结论0.5%心居康杀白蚁饵剂均可以达到消灭台湾乳白蚁的整个族群。  相似文献   
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