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Summary— To investigate if the functional alterations observed in resistance arteries of spontaneously hypertensive rats (SHRs) were also present at the coronary level, in vitro experiments were performed in mesenteric resistance arteries (MRA) and in right (RIC) and left interventricular coronary (LIC) arteries taken from 15–25-week-old SHR and age-matched Wistar Kyoto rats WKYs. Using a passive extension protocol, internal diameters corresponding to 100 mmHg intraluminal pressure (D100) were determined and vessels were set up to a normalized internal diameter (0.9 D100). SHR mesenteric resistance arteries had a significantly smaller diameter compared to WKY arteries, whereas both types of SHR coronary arteries had a greater diameter compared to those of WKY rats. In arteries in the absence of contracting agonist, nitro-L-arginine (NOLA, 100 μM) induced a progressive rise in basal tone, which could be reversed by subsequent addition of L-arginine (100 μM) but not D-arginine (100 μM). When expressed as percent of maximal contractions induced by agonists (noradrenaline, NA [10 μM] in MRA; serotonin, 5-HT [10 μM], in RIC and LIC), these contractions were significantly stronger in WKY compared to SHR coronary and mesenteric resistance arteries. In NA-precontracted MRA and 5HT-precontracted coronary arteries in the presence of indomethacin (10 μM), the magnitude of acetylcholine-induced maximal relaxations (expressed as percent of maximal contractions induced by agonists) was greater in WKY compared to SHR arteries. After a 30-min incubation period, NOLA (100 μM) completely inhibited relaxations induced by acetylcholine (0.01–10 μM) in all types of precontracted arteries. Subsequent additions of sodium nitroprusside, (SNP, 10 μM) induced complete relaxations in all preparations. These results show that a basal release of NO or NO-like compound by endothelial cells is present in isolated mesenteric resistance and coronary arteries of WKY rats and SHRs. The contribution of endothelium-derived relaxing factor-nitric oxide (EDRF-NO) to arterial tone was lower in MRA compared to coronary arteries in both strains and in SHR compared to WKY arteries. In the SHR preparations, the impaired relaxation induced by acetylcholine appeared to be due to a functional alteration of the endothelium in the presence of normal reactivity of the smooth muscle cells. 相似文献
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表小檗碱对α受体的作用 总被引:2,自引:0,他引:2
表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择 相似文献
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AIMS: Diabetic ketoacidosis (DKA), a life-threatening acute complication of Type 1 diabetes, may be preventable with frequent monitoring of glycaemia and ketosis along with timely supplemental insulin. This prospective, two-centre study assessed sick day management using blood 3-hydroxybutyrate (3-OHB) monitoring compared with traditional urine ketone testing, aimed at averting emergency assessment and hospitalization. METHODS: One hundred and twenty-three children, adolescents and young adults, aged 3-22 years, and their families received sick day education. Participants were randomized to receive either a blood glucose monitor that also measures blood 3-OHB (blood ketone group, n = 62) or a monitor plus urine ketone strips (urine ketone group, n = 61). All were encouraged to check glucose levels > or = 3 times daily and to check ketones during acute illness or stress, when glucose levels were consistently elevated (> or = 13.9 mmol/l on two consecutive readings), or when symptoms of DKA were present. Frequency of sick days, hyperglycaemia, ketosis, and hospitalization/emergency assessment were ascertained prospectively for 6 months. RESULTS: There were 578 sick days during 21,548 days of follow-up. Participants in the blood ketone group checked ketones significantly more during sick days (276 of 304 episodes, 90.8%) than participants in the urine ketone group (168 of 274 episodes, 61.3%) (P < 0.001). The incidence of hospitalization/emergency assessment was significantly lower in the blood ketone group (38/100 patient-years) compared with the urine ketone group (75/100 patient-years) (P = 0.05). CONCLUSIONS: Blood ketone monitoring during sick days appears acceptable to and preferred by young people with Type 1 diabetes. Routine implementation of blood 3-OHB monitoring for the management of sick days and impending DKA can potentially reduce hospitalization/emergency assessment compared with urine ketone testing and offers potential cost savings. 相似文献
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目的研究先天性腹裂的肠管受损害情况,探讨该病术后并发症的原因。方法利用大鼠腹裂模型,运用组织学、生化学和免疫组织化学方法,分析腹裂胎鼠肠管的组织结构,DNA和蛋白质,细胞增生和凋亡等方面的改变。结果共获得腹裂胎鼠16只,对照胎鼠21只。与对照组相比,腹裂鼠肠管变短、充血水肿、粘连,肠壁表面纤维覆盖,壁内胶原沉积,DNA总量下降,蛋白质总量基本不变,细胞增生率下降,凋亡率上升。结论腹裂的肠管损伤是多方面的,是术后肠管运动和吸收功能异常的原因,大鼠的腹裂模型是对先天性腹裂的病因、病理等方面研究的合适工具。 相似文献
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Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献