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Objective:To investigate the vasodilatative roles and mechanisms of 17 ? estradiol(E 2) on rat thoracic aortas (TA). Methods:Rings cut from thoracic aortas of female rats were used by in vitro perfusion. The endothelium dependent and endothelium independent vasorelaxing effects of E 2 were measured. Furthermore, it was also observed whether the relaxing effects of E 2 were modulated by tamoxifen, N ? nitro L arginine methyl ester(L NAME),TEA, methylene blue(MB) or Methylene Blue(MB).Results:E 2 caused acute concentration dependent relaxation in TA with endothelium, but not significant without endothelium( P
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Objective To explore the method of atrial septal defect (ASD)occlusion with occluder by minimally invasive chest ways. Methods 34 patients with ASD were anaesthetized and a 2cm～3cm-long incision was made in the 4th intercostal space of right side of sternum and a Dasdo round or elliptic occluder was placed in the heart.The ASD size and edge in various sections were measured by transesophageal echocardiography,and the type and size of occluder were accordingly selected.Two umbrellas were opened on two sides of ASD under monitoring of echocardiography.After confirming the firm of occluder and no evident atrial shunt,occluder was released,and right atrium and chest were sewed. Results 33 patients with ASD were successfully occluded and one case was failed who received extracorporeal circulation operation.The maximum diameter of ASD was 8～32(19 3?6 3)mm.The shortest edge in variant side was 0 mm to posterior wall of aortea,3.5mm to superior vena cava,6.0mm to inferior vena cava and 6.0mm to the base of mitral valve.The time for closing ASD guided by echocardiography was about 2～3 minutes. Conclusions The placement of ASD occluder through minimal incision of the chest is a new method for the treatment of ASD.It might have wider indications for ASD occlusion.
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Objective To evaluate the protective effects of stroma-free bovine hemoglobin(SFBHB)on preservation of the donor heart.Methods 24 isolated perfused rabbit hearts were equally divided into two groups.In control group,the cardiac arrest were induced with St Thomas Ⅱ solution and repeated every 30 min.the myocardial temperature remained at 40℃.In experimental group,the isolated rabbit hearts were perfused continuously with St Thomas Ⅱ solution containing stroma-free bovine hemoglobin and the myocardial temperature remained at 37℃.The preservation lasted 6 h.Results There were significant differences between the two groups in the follows:(1)The mean values of the left ventricular developed pressure(LVDP)and coronary flow rate(CFR)were higher in experimental group(P＜0.001);(2)The ATP level and myocardial oxygen uptake were significantly decreased in control group(P＜0.001);(3)The mean values of released creatine phosphate kinase(CPK),lactec dehydrogenase(LDH)and myocardial contents of malondialdehyde(MDA)were higher in control group(P＜0.01);(4)More water was present in the myocardial in control group(P＜0.01);(5)The myocardial ultrastructural injuries were greater in control group.Conclusion The stroma-free bovine hemoglobin could offer great protective effects on preservation of the isolated rabbit hearts.