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41.
The objective of this study was to determine the effects of flavonoids on the in vitro monocarboxylate transporter 1 (MCT1)-mediated transport and in vivo disposition of the drug of abuse, gamma-hydroxybutyrate (GHB). The uptake of GHB in rat MCT1 gene-transfected MDA-MB231 cells was significantly decreased in the presence of the flavonoids apigenin, biochanin A, chrysin, diosemin, fisetin, genistein, hesperitin, kaempferol, luteolin, morin, narigenin, phloretin, and quercetin, but was not affected by the flavonoid glycosides phloridzin and rutin. The IC(50) values for luteolin, morin, and phloretin were 0.41 +/- 0.14, 6.41 +/- 2.01, and 2.57 +/- 0.48 microM, with the inhibition mechanism for luteolin being competitive. [(3)H]Kaempferol and [(3)H]biochanin A did not exhibit MCT1-mediated uptake, suggesting that these flavonoids are not substrates for MCT1. The combination of luteolin and phloretin inhibited the uptake of GHB in a synergistic manner; however, the combination of luteolin and morin was antagonistic. GHB 1000 mg/kg was administered to rats by i.v. bolus, with or without the concomitant administration of luteolin 10 mg/kg i.v. After luteolin treatment, the renal and total clearances of GHB were significantly increased, probably because of inhibition of the MCT1-mediated renal reabsorption of GHB, and the sleep time significantly decreased (121 +/- 5 min versus 165 +/- 10 min) compared with control rats. Overall, the results of this study indicate that flavonoids from food or herbal products may significantly alter the pharmacokinetics and pharmacodynamics of MCT substrates.  相似文献   
42.
先天性胃壁肌层缺损诊治体会   总被引:1,自引:0,他引:1  
目的 探讨提高新生儿先天性胃壁肌层缺损治愈率的方法。方法 总结分析近年来收治的本症11例患儿(均经过病理检验证实)的临床及相关资料。结果 11例患儿中,8例存活,其中7例为近十年的病例。1例死亡,2例放弃治疗,均为十年以前的病例。在存活者中,经追踪观察及消化道造影检查,残胃有明显代偿性生长,患儿生长发育未受到明显的影响。结论 早期发现、及时手术、控制感染、术后营养、支持治疗,其预后良好。  相似文献   
43.
目的 探讨微创经皮肾镜取石术治疗上尿路结石的有效性和安全性.方法上尿路结石患者368例,平均年龄57岁.其中输尿管上段结石116例,结石大小(2.1±0.8)cm;肾结石252例,结石大小(4.6±1.4)cm,其中非鹿角形结石190例,结石大小(3.2±1.1)cm,鹿角形结石62例,结石大小(7.6±1.6)cm.均采用微创经皮肾穿刺,输尿管镜下气压弹道或联合钬激光碎石治疗,对结石清除率和并发症等进行统计分析.结果 368例患者中单通道取石356例(96.7%),双通道12例(3.3%).一期取石344例(93.5%),二期取石24例(6.5%).总结石取净率为88.6%(326/368).平均手术时间73 min.一期取净结石者住院时间4~8 d,平均6 d.术后发热14例(3.8%);输血5例(1.4%);2例肾结石术后出血严重者经输血及超选择性肾动脉栓塞后治愈.结论 微创经皮肾镜取石术损伤小、住院时间短、术中出血及并发症少、结石清除率高、可重复取石,是治疗上尿路结石有效的微创手段.  相似文献   
44.
Bone marrow stromal cells (MSCs) increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis after stroke. Angiopoietin-1 (Ang1) and its receptor Tie2 mediate vascular integrity and angiogenesis as does VEGF and its receptors. In this study, we tested whether MSC treatment of stroke increases Ang1/Tie2 expression, and whether Ang1/Tie2 with VEGF/ vascular endothelial growth factor receptor 2 (VEGFR2) (Flk1), in combination, induced by MSCs enhances angiogenesis and vascular integrity. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAo) and treated with or without MSCs. Marrow stromal cell treatment significantly decreased blood-brain barrier (BBB) leakage and increased Ang1, Tie2, and occludin (a tight junction protein) expression in the ischemic border compared with MCAo control. To further test the mechanisms of MSC-induced angiogenesis and vascular stabilization, cocultures of MSCs with mouse brain endothelial cells (MBECs) or astrocytes were performed. Supernatant derived from MSCs cocultured with MBECs significantly increased MBEC expression of Ang1/Tie2 and Flk1 compared with MBEC alone. Marrow stromal cells cocultured with astrocytes also significantly increased astrocyte VEGF and Ang1/Tie2 expression compared with astrocyte culture alone. Conditioned media from MSCs alone, and media from cocultures of MSCs with astrocytes or MBECs, all significantly increased capillary tube-like formation of MBEC compared with control Dulbecco's modified Eagle's medium media. Inhibition of Flk1 and/or Ang1 significantly decreased MSC-induced MBEC tube formation. Knockdown of Tie2 expression in MBECs significantly inhibited MSC-induced tube formation. Our data indicate MSC treatment of stroke promotes angiogenesis and vascular stabilization, which is at least partially mediated by VEGF/Flk1 and Ang1/Tie2.  相似文献   
45.
Glial glutamate transporter-1 (GLT-1) plays an essential role in removing glutamate from the extracellular space and maintaining the glutamate below neurotoxic level in the brain. To explore whether GLT-1 plays a role in the acquisition of brain ischemic tolerance (BIT) induced by cerebral ischemic preconditioning (CIP), the present study was undertaken to observe in vivo changes in the expression of GLT-1 and glial fibrillary acidic protein (GFAP) in the CA1 hippocampus during the induction of BIT, and the effect of dihydrokainate (DHK), an inhibitor of GLT-1, on the acquisition of BIT in rats. Immunohistochemistry for GFAP showed that the processes of astrocytes were prolonged after a CIP 2 days before the lethal ischemic insult, which could protect pyramidal neurons in the CA1 hippocampus against delayed neuronal death induced normally by lethal ischemic insult. The prolonged processes extended into the area between the pyramidal neurons and tightly surrounded them. These changes made the pyramidal layer look like a 'shape grid'. Simultaneously, the prolonged and extended processes showed a great deal of GLT-1. Western blotting analysis showed significant upregulation of GLT-1 expression after the CIP, especially when it was administered 2 days before the subsequent lethal ischemic insult. Neuropathological evaluation by thionin staining showed that DHK dose-dependently blocked the protective role of CIP against delayed neuronal death induced normally by lethal brain ischemia. It might be concluded that the surrounding of pyramidal neurons by astrocytes and upregulation of GLT-1 induced by CIP played an important role in the acquisition of the BIT induced by CIP.  相似文献   
46.
目的 判定增龄对皮肤血流量的影响。方法 用PIM2-LDPI检测皮肤血流量。结果 老年组前额、左手指背、命门穴部位皮肤血流量分别为:(1.94±0.86)V,(1.92±0.52)V和(0.71±0.19)V,与青年组比较差异无显著性。但是,老年男性在命门穴的皮肤血流量明显高于青年男性(P<0.05),老年女性前额的皮肤血流量明显降低(P<0.01)。男性比女性的皮肤血流量高。结论 皮肤血流量的差异无年龄相关性,男性组的皮肤血流量比女性组高。  相似文献   
47.
目的探讨外周高渗刺激激活下丘脑室旁核(PVN)神经元的细胞类别。方法以腹腔注射高渗盐水作为外周高渗刺激。细胞外记录PVN神经元单位放电的变化,并用免疫细胞化学方法观察PVN中los的表达及los表达阳性神经元的性质。结果腹腔注射高渗盐水使PVN的位相型放电神经元兴奋,PVN内los表达明显增加,特别是PVN大细胞中大量的los阳性神经元同时表达精氨酸加压索(AVP)。结论外周高渗刺激能够激活PVN内的加压索(VP)能神经元。  相似文献   
48.
高歌  何露 《中国卫生统计》2003,20(5):276-278
目的 对多分类有序反应变量logistic回归的应用条件寻求科学合理的检验方法。方法 使用卡方分布的理论,SAS软件及抽样调查方法。结果 设计出多分类有序反应变量logistic回归应用条件的卡方检验方法,推导出反应变量取各水平的概率计算公式及卡方检验中理论值、自由度的计算公式,并在作者主持的国家医师资格临床实践技能考试研究中取得了成功效果。结论 多分类有序反应变量logistic回归得到完善和补充,具有较大的理论和实际意义。  相似文献   
49.
诱导型一氧化氮合酶在前列腺增生组织中表达的研究   总被引:1,自引:0,他引:1  
目的:探讨诱导型一氧化氮合酶(iNOS)与前列腺增生(BPH)病理生理变化的关系。方法:用免疫组化法检测10例正常和30例有膀胱出口梗阻的BPH患者膀胱和前列腺组织中iNOS的表达。结果:BPH组前列腺组织中iNOS呈阳性染色,主要分布于前列腺的上皮细胞及上皮下组织中,间质平滑肌组织中均为阴性;对照组的膀胱壁、膀胱颈部和前列腺组织中均无iNOS阳性染色。结论:iNOS仅在BPH患者前列腺组织中有特异性表达,提示它参与了前列腺增生的病理生理过程。  相似文献   
50.
Objective: To summarize the clinical outcomes of 117 human vitrified blastocyst transfer cycles and to determine the impact factors.Methods: In IVF-ET cycles, supernumerary embryos were cultured to 5-Day(D5) or 6-Day(D6), blastocysts of various stages were cryopreserved by vitrification using cryoloops. Survival rate and clinical pregnancy rate were observed.Results: A total of 312 blastocysts were thawed in 117 frozen embryo transfer cycles, the survival rate was 90.7% (283/312) after thawing. After the transfer of 230 blastocysts in 115 cycles, 69.6% (80/115) of the women got clinically pregnant, and 17.5% (14/80) of them suffered from miscarriage, 39 healthy babies were born in 28 deliveries, and the other 38 pregnancies are ongoing. The implantation rate was 47.4% (109/230). In 107 transfer cycles with 2 hatched blastocysts transferred in each cycle, 72.9% (78/107) got clinically pregnant, while in 8 cycles with 1 or no hatched blastocysts in the two transferred blastocysts, the clinical pregnancy rate is 25%(2/8). The clinical pregnancy rates were not statistically different between natural (77.4%, 24/31) or artificial endometrium preparation (66.7%, 56/84) cycles. Conclusions: These findings suggest that blastocyst vitrification is effective in terms of implantation rate and pregnancy outcome. Transferring of two hatched blastocyst can achieve a higher pregnancy rate.  相似文献   
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