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991.
Kazuo Umemura Shinji Watanabe Kazunao Kondo Hisakuni Hashimoto Mitsuyoshi Nakashima 《Atherosclerosis》1997,130(1-2):11-16
The inhibitory effect of prostaglandin E1, which has an anti-platelet action and a vasodilating action via intracellular cyclic AMP elevation, was studied on intimal thickening in the rat femoral artery. A segment of the femoral artery was occluded by a platelet and fibrin-rich thrombus due to photochemical reaction between systemically administered Rose Bengal and transluminal green light which causes endothelial injury followed by platelet adhesion and aggregation at the site of photochemical reaction. Three weeks after endothelial injury, intimal thickening occurred at the irradiated site. Prostaglandin E1 (0.3 μg/kg per min), administered as a continuous infusion 10 min before photochemical reaction significantly (P<0.05) prolonged the time to occlusion of the femoral artery. In a separate experiment, prostaglandin E1 (0.3 μg/kg per min) administered as a continuous infusion for 7 days just after endothelial injury significantly (P<0.05) inhibited intimal thickening compared with a control group. In cultured rat-derived vascular smooth muscle cells, prostaglandin E1 produced concentration-dependent inhibition of migration and proliferation, stimulated by platelet-derived growth factor. These results suggest that prostaglandin E1 may be effective in preventing vascular restenosis after vascular surgery and angioplasty. 相似文献
992.
E N Moore J F Spear L N Horowitz H S Feldman R A Moller 《The American journal of cardiology》1978,41(4):703-709
Tocainide (Astra W36095) is an orally active antiarrhythmic drug that is structurally related to lidocaine. This paper describes in vivo and in vitro studies undertaken to assay the electrophysiologic properties of this compound. Ouabain-induced ventricular ectopic activity was abolished by this drug in both isolated canine Purkinje fibers and in intact dogs. Similarly, the ventricular ectopic activity that occurs 24 hours after the two stage Harris coronary arterial ligation procedure also was abolished by tocainide. The amount of current necessary to evoke an action potential by intracell stimulation during diastole was Increased in direct relation to drug concentration. Similarly, in dogs anesthetized with pentobarbital sodium, tocainide increased the ventricular fibrillation threshold up to 150 percent above control values during normal supraventricular rhythm and up to 285 percent after premature ventricular beats. The transmembrane action potential duration and effective refractory period of isolated canine Purkinje fibers were shortened by tocainide. Tocainide depressed atrioventricular nodal conduction in anesthetized dogs, an effect that was magnified in the presence of premature atrial beats but had no effect on His, Purkinje or ventricular muscle conduction. These results Indicate that tocainide is a potentially effective antiarrhythmic agent and deserves further investigation in patients. 相似文献
993.
994.
Follicular variant of papillary thyroid carcinoma with B‐type RafV600E showing higher frequency of suspicious sonographic features and multifocality 下载免费PDF全文
995.
996.
《Diagnostic and interventional imaging》2015,96(4):373-381
ObjectivesThe goals of the study were to describe the MR imaging features of endometriosis of the urinary tract and identify those that suggest intrinsic involvement of ureteric wall.Materials and methodsThirty-five women with proven urinary tract endometriosis and who had preoperative MR imaging between 2001 and 2011 were included retrospectively. MR images were intrepreted by one junior and one senior radiologists. To characterize the intrinsic parietal involvement, the ureteric circumference involved by the lesion of endometriosis was noted.ResultsThirty-eight ureteric and 13 bladder lesions were analyzed. They were found in association in nine women. Ureteric lesions were bilateral in seven women. Of the 38 ureteric lesions, 27 were extrinsic and 11 intrinsic at histopathological analysis. Sixteen women with extrinsic lesions and 10 with intrinsic ones were correctly identified on MR imaging. When the ureter was included less than 360° in the lesion, extrinsic involvement was confirmed in 80% of cases.ConclusionMR imaging appears to be more sensitive (91%vs 82%) but less specific (59% vs 67%) than surgery for the diagnosis of intrinsic form of ureteric location. 相似文献
997.
Ambar Oyarzábal Yohani Pérez Vivian Molina Rosa Mas Yazmin Ravelo Sonia Jiménez 《Translational andrology and urology》2015,4(4):391-397
Background
Lower urinary tract symptoms (LUTS) in patients with benign prostatic hyperplasia (BPH) mainly depend on alpha1-adrenoreceptors (α1-ADR) stimulation, but a link with oxidative stress (OS) is also involved. D-004, a lipid extract of Roystonea regia fruits, antagonizes ADR-induced responses and produces antioxidant effects. The objective of this study was to investigate whether D-004 produce antioxidant effects in rats with phenylephrine (PHE)-induced urodynamic changes.Methods
Rats were randomized into eight groups (ten rats/group): a negative vehicle control and seven groups injected with PHE: a positive control, three treated with D-004 (200, 400 and 800 mg/kg) and three others with tamsulosin (0.4 mg/kg), grape seed extract (GSE) (250 mg/kg) and vitamin E (VE) (250 mg/kg), respectively.Results
Effects on urinary total volume (UTV), volume voided per micturition (VM), malondialdehyde (MDA) and carbonyl groups (CG) concentrations in prostate and bladder homogenates were study outcomes. While VM and UTV lowered significantly in the positive control as compared to the negative control group, the opposite occurred with prostate and bladder MDA and CG values. D-004 (200-800 mg/kg) increased significantly both VM and UTV, lowered significantly MDA in prostate and bladder homogenates, and reduced GC levels only in the prostate. Tamsulosin increased significantly VM and UTV, but unchanged oxidative variables. GSE and VE unchanged the UTV, whereas VE, not GSE, modestly but significantly attenuated the PHE-induced decrease of VM.Conclusions
Single oral administration of D-004 (200-800 mg/kg) was the only treatment that ameliorated the urodynamic changes and reduced increased oxidative variables in the prostate of rats with PHE-induced prostate hyperplasia. 相似文献998.
Li-Ye Wei Xiang-Hua Fu Wei Li Xi-Le Bi Shi-Ru Bai Kun Xing Yan-Bo Wang 《中华医学杂志(英文版)》2015,128(9):1147-1150
Background:
Several studies have demonstrated that primary percutaneous coronary intervention (PCI) can result in reperfusion injury. This study aims to investigate the effectiveness of liposomal prostaglandin E1 (Lipo-PGE1, Alprostadil, Beijing Tide Pharmaceutical Co., Ltd.) for enhancing microcirculation in reperfusion injury. In addition, this study determined the optimal administration method for acute ST elevation myocardial infarction (STEMI) patients undergoing primary PCI.Methods:
Totally, 68 patients with STEMI were randomly assigned to two groups: intravenous administration of Lipo-PGE1 (Group A), and no Lipo-PGE1 administration (Group B). The corrected thrombolysis in myocardial infarction (TIMI) frame count (cTFC) and myocardial blush grade (MBG) were calculated. Patients were followed up for 6 months. Major adverse cardiac events (MACE) were also measured.Results:
There was no significant difference in the baseline characteristics between the two groups. The cTFC parameter in Group A was significantly lower than Group B (18.06 ± 2.06 vs. 25.31 ± 2.59, P < 0.01). The ratio of final MBG grade-3 was significantly higher (P < 0.05) in Group A (87.9%) relative to Group B (65.7%). There was no significant difference between the two groups in final TIMI-3 flow and no-reflow. Patients were followed up for 6 months, and the occurrence of MACE in Group A was significantly lower than that in Group B (6.1% vs. 25.9% respectively, P < 0.05).Conclusions:
Myocardial microcirculation of reperfusion injury in patients with STEMI, after primary PCI, can be improved by administering Lipo-PGE1. 相似文献999.
目的 研究江西省老年人载脂蛋白E基因( ApoE)多态性的分布及其与轻度认知功能障碍( MCI)的关系. 方法以符合美国精神障碍诊断与统计手册第4版( DSM-IV)诊断标准的120例MCI老人作为患者组,以120例健康体检者作为对照组,使用聚合酶链反应对其进行ApoE基因多态性的检测. 结果 两组人群中ApoEε3/3基因型分布的百分比最大,其次为ApoEε3/4,而ApoEε2/2最少;患者组和对照组ApoEε4基因频率分别为14. 17%、7. 91%,两者比较差异有统计学意义(χ2 =4. 77,P<0. 05),两组人群中ApoEε3等位基因分布的百分比最大;ApoEε4等位基因与MCI呈正相关性(OR =1. 92,P =0. 029). 结论 江西省汉族老人中, ApoEε3/3为最常见的基因型, ApoEε3 为最常见的等位基因,ApoEε4等位基因可能是老年人MCI发病的危险因子. 相似文献
1000.
目的:分析BRAFV600E基因突变在非小细胞肺癌阳性胸水中的表达情况。方法将胸水内查见肺腺癌细胞的病例24例其阳性胸水离心沉渣制作细胞块。分离细胞块样品 DNA ,使用扩增突变系统(ARMS )方法进行 PCR 扩增,检测BRAFV600E基因突变情况。结果检测成功率为100%,突变检出率为8%,检出突变2例,男性及女性各1例,FAM 信号Ct值分别为18.7及17.8,STD的 FAM 信号Ct值为18。结论可以应用非小细胞肺癌阳性胸水代替肺癌肿瘤组织检测BRA FV600E基因突变,对指导晚期非小细胞肺癌病人靶向药物治疗具有重要指导意义。 相似文献