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51.
The authors report a case of internal mammary artery graft anastomosed to the left anterior descending coronary artery (LADC) which was found to be non functional in the early post-operative period (one month) but second catheterization at one year revealed the graft to be patent with thrombosis of the LADC. This case shows the flow adjustment possibilities of internal mammary artery graft. 相似文献
52.
Halbach VV; Higashida RT; Hieshima GB; Reicher M; Norman D; Newton TH 《Radiology》1987,163(2):437-442
Thirty symptomatic indirect carotid cavernous fistulas were treated between 1978 and 1986 with a variety of treatment modalities. Combined carotid artery and jugular vein compression resulted in a complete cure in seven of 23 patients (30%) and improvement in one additional patient. There were no complications from this treatment, which is performed by the patient on an outpatient basis. Patients in whom carotid jugular compression therapy failed or who demonstrated cortical venous drainage or visual decline were treated with intravascular embolization. Embolization resulted in complete cure in 17 of 22 (77%) and improvement in four of 22 (18%). One patient required surgical excision of the involved dura after embolization to achieve complete cure. There was one permanent complication (stroke), which resulted in mild weakness caused by clot formation on a catheter. 相似文献
53.
M Brignole C Menozzi B Sartore M Barra G Lolli I Monducci 《Giornale italiano di cardiologia》1987,17(8):642-652
We studied the unnatural history of sinus node function in severe sick sinus syndrome treated with AAI or DDD pacemakers. In 19 patients (10 m; 9 f; mean age +/- 1 SD 69 +/- 7 years) we executed serial bicycle exercise tests and electrophysiological studies before, 7 days and 3 months after pacemaker implant. Sinus heart rate at maximum effort was: 118 +/- 23 beats/min and 117 +/- 23 beats/min (two different evaluations) before pacemaker implant, 125 +/- 21 beats/min after 7 days (p less than 0.05) and 133 +/- 20 beats/min after 3 months (p less than 0.001) with an average increment of 12.7%. A positive correlation (y = 50.4 + 0.7 X beats/min; p less than 0.001) between the first basal test and the third month one was found. In analogy exercise test lasted 8.7 +/- 3, 8.6 +/- 2.8, 9.5 +/- 2.5, 9.7 +/- 2.5 minutes respectively, with an average increment of 11.5% between the first basal test and the third month one. Sinus heart rate at maximum effort in 14 age matched normal subjects was 138 +/- 15 beats/min. The difference with sick sinus syndrome patients was statistical (p less than 0.05) when compared with the basal test but not with 3rd month test. Parameters determined during electrophysiological studies were: spontaneous heart rate, corrected sinus node recovery time, sino-atrial conduction time evaluated before and after autonomic blockade (propranolol 0.2 mg/kg i.v. plus atropine 0.04 mg/kg i.v.). All these parameters, excepting basal corrected sinus node recovery time, improved significantly after pacemaker implant.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
54.
55.
Walkowiak J Herzig KH Witt M Pogorzelski A Piotrowski R Barra E Sobczynska-Tomaszewska A Trawinska-Bartnicka M Strzykala K Cichy W Sands D Rutkiewicz E Krawczynski M 《European journal of clinical investigation》2001,31(9):796-801
BACKGROUND: Cystic fibrosis (CF) is the most common cause of exocrine pancreatic insufficiency in childhood. The aim of the present study is to evaluate the correlation between genotype and exocrine pancreatic insufficiency in CF patients. The special emphasis was put on the analysis of mild CFTR mutations. DESIGN: The study comprised 394 CF patients and 105 healthy subjects (HS). Elastase-1 concentrations were measured in all subjects. RESULTS: Severe pancreatic insufficiency was associated with the presence of two CFTR gene mutations (DeltaF508, N1303K, CFTR dele 2,3 (21kb), G542X, 1717-1G-A, R533X, W1282X, 621GT, 2183AAG, R560T, 2184insA and DeltaI507, G551D, 895T) and mild insufficiency with the presence of at least one mutation (R117H, 3171insC, A155P2, 138insL, 296 + 1G-A, E92GK, E217G, 2789 + 5G-A. 3849 + 1kbC-T/3849 + 1kbC-T) genotype resulted in high elastase-1-values. However, in case of patients with genotype DeltaF508/3849 + 10kbC-T, 1717-1GA/3849 + 10kbC-T as well as with DeltaF508/R334W, both high and low elastase-1 concentrations were found. Low E1 values were found in a patient with DeltaF508/R347P genotype. CONCLUSION: Patients who carry two 'severe' mutations develop pancreatic insufficiency, whereas those who carry at least one 'mild' usually remain pancreatic sufficient. However, the presence of one mild mutation does not exclude pancreatic insufficiency. 相似文献
56.
Blood group A immunodeterminants on human red cells differ in biologic activity and sensitivity to alpha-N-acetylgalactosaminidase 总被引:1,自引:0,他引:1
BACKGROUND: Epitopes of blood group A antigen can be enzymatically cleaved from red cells (RBCs), but the extent of cleavage required for normal survival in allogeneic blood transfusion recipients is unknown. Therefore, the cleavage rates were studied for A antigen epitope binding of 1) complement-activating anti-A, 2) Dolichos biflorus anti- A, lectin, and 3) hemagglutinating anti-A during incubation with a purified alpha-N-acetylgalactosaminidase, E.C. 3.2.1.49 (alpha- GalNAc'ase). STUDY DESIGN AND METHODS: Suspensions of group A RBCs were incubated with alpha-GalNAc'ase. Cells were removed at intervals, washed, and tested for loss of binding by monoclonal, polyclonal, and complement-activating anti-A, D. biflorus anti-A1 lectin, and Ulex europaeus anti-H lectin. RESULTS: A epitopes binding D. biflorus lectin were highly susceptible to alpha-GalNAc'ase; simultaneously with their loss, binding with U. europaeus lectin emerged. Loss of complement- mediated hemolysis was slower. A epitopes binding hemagglutinating anti- A were most resistant. Cleavage of A epitopes from membrane glycosphingolipids with short oligosaccharide chains was similarly resistant. Rates of cleavage from A1 and A2 RBCs were similar. CONCLUSION: RBC epitopes of blood group A differ in susceptibility to cleavage and biologic reactivity, which suggests that subsets mediating important biologic functions exist on functionally and topographically distinct membrane glycoconjugates. 相似文献
57.
BACKGROUND: Concern over the theoretical possibility of disease transmission via blood from donors who develop Creutzfeldt-Jakob disease has led to proposals to exclude older individuals from donating plasma for further manufacture into pooled plasma donations. The impact of extending this age-deferral policy to blood donors was examined with respect to the risk for known transmissible viruses. STUDY DESIGN AND METHODS: Demographic characteristics and confirmed prevalence rates (/10(5) first-time donations) and incidence rates (/10(5) person-years for repeat donors) for viral markers were compared for donors < 50 years old (n = 1,259,805 [85%]) and > or = 50 years old (n = 219,856 [15%]) and for donors < 60 years old (n = 1,409,176 [95%]) and > or = 60 years old (n = 70,485 [5%]). Incidence rates were combined with infectious window-period estimates for each virus, to calculate the risk of virus transmission per 10(6) donations. RESULTS: Unadjusted prevalence rates were significantly greater for younger than for older donor groups for human immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg), and hepatitis C virus (HCV) (p < or = 0.05). Incidence rates (and transmission risk estimates) for HBsAg were significantly higher in the < 50 donor group than in the > or = 50 group (p < or = 0.05), and those for HIV, human T-lymphotropic virus, and HCV were not significantly higher (p > 0.05). Blanket removal of donors over the age of 50 would potentially lead to the following significant increases in the risk of infected units: HIV, 12 percent; HCV, 21 percent; and hepatitis B virus (HBsAg), 22 percent. CONCLUSION: Removal of donors over the age of 60 would not significantly affect the risk of infected units. Deferral of donors > or = 50 years of age from whole-blood donations for unfounded concerns about Creutzfeldt-Jakob disease could have adverse effects on both blood availability and safety. 相似文献
58.
壳聚糖/聚乙二醇琥珀酸酯薄膜的制备及其与肌成纤维细胞的相容性 总被引:1,自引:0,他引:1
目的:制备防粘连壳聚糖/聚乙二醇琥珀酸酯薄膜并观察其与肌成纤维细胞的相容性。方法:实验于2006-05/11在南方医科大学附属珠江医院中心实验室完成。实验材料:在透析后的壳聚糖与聚乙二醇琥珀酸酯或聚乙二醇共混后置入冻干机冻干制得壳聚糖/聚乙二醇琥珀酸酯薄膜或壳聚糖/聚乙二醇膜,并将新生2~5d的SD大鼠骨骼肌成纤维细胞种植于膜片上。实验评估:①MTT法测定肌成纤维细胞接种在不同膜片上的吸光度值,计算相对贴附率。相对贴附率=不同膜的A490nm/培养板的A490nm×100%。②MTT法测定肌成纤维细胞在不同膜片上的生长1,5d后的吸光度值。③相差显微镜下观察肌成纤维细胞的生长形貌。结果:①肌成纤维细胞在不同膜片上的贴附率:肌成纤维细胞在壳聚糖/聚乙二醇琥珀酸酯薄膜上能良好黏附、增殖,而在壳聚糖/聚乙二醇膜、壳聚糖膜上黏附性差。联合培养12h,5d后MTT法结果显示,壳聚糖/聚乙二醇琥珀酸酯组的A值分别为0.074±0.009,0.141±0.031,分别为壳聚糖组的6.17倍和6.13倍(P〈0.05)。②肌成纤维细胞的生长特性:肌成纤维细胞在壳聚糖/聚乙二醇琥珀酸酯膜上的活性最高,增殖能力最强,增长速度最快,其次为壳聚糖/聚乙二醇膜,但两者差异无显著性意义(P〉0.05),而细胞在壳聚糖膜上的增殖能力较低,膜上细胞数目较少,与其他组比较差异有显著性意义(P〈0.05)。③肌成纤维细胞与不同膜片联合培养1,5d时的生长形貌:壳聚糖膜上细胞未贴壁生长,为透明的圆球形,呈游离状态,未能很好舒展,且有些皱缩,生长活力也不旺盛;细胞与壳聚糖/聚乙二醇膜、壳聚糖/聚乙二醇琥珀酸酯膜片联合培养的生长情况要明显好于壳聚糖膜,细胞相互融合成片,多呈长梭形,细胞间隙狭窄,紧密排列成束,成指纹状结构且聚集生长的趋势也更明显。结论:将接支琥珀酰基的聚乙二醇与壳聚糖共混组成的网状系统改进了膜片的力学性能,提高了膜片的柔韧性,使其成膜性更好;壳聚糖/聚乙二醇琥珀酸酯薄膜具有良好的生物相容性,肌成纤维细胞在壳聚糖/聚乙二醇琥珀酸酯薄膜上的黏附及生长情况明显好于壳聚糖薄膜。 相似文献
59.
A J Crottogini P Willshaw J G Barra R Armentano E I Cabrera Fischer R H Pichel 《Circulation》1987,76(5):1115-1126
We tested the ability of the slope (Emax) and the volume intercept (Vo) of the end-systolic pressure-volume relationship (ESPVR) to indicate contractility changes in conscious dogs instrumented with sonomicrometers measuring left ventricular diameter in three orthogonal axes and a left ventricular pressure microtransducer. ESPVRs were generated by inferior vena caval occlusion under control conditions (C1 and C2) and during enhanced (I+) and depressed (I-) inotropic states achieved by infusion of dobutamine and injection of propranolol, respectively. No significant difference between the first control (C1) and I+ or between the second control (C2) and I- were found for either Emax (C1, 5.31 +/- 1.68 mm Hg/ml, mean +/- SD; I+, 5.37 +/- 1.44; C2, 5.20 +/- 1.62; I-, 4.18 +/- 1.32) or Vo (C1, 10.3 +/- 9.6 ml; I+, 7.3 +/- 9.1; C2, 9.9 +/- 9.0; I-, 12.7 +/- 12.5), despite significant changes in other indexes of contractility. Comparison of changes in Emax in individual animals in response to I+ and I- revealed that 63% were nonsignificant, 28% were significant and expected, and 9% were significant and paradoxical. Within defined volume limits and irrespective of individual changes in Emax and Vo, in all animals I+ shifted the ESPVR above and to the left of C1 and I- shifted the ESPVR below and to the right of C2. We thus integrated the changes in Emax and Vo by measuring the area beneath each ESPVR between defined limits of end-systolic volume. The values for area were: C1, 612 +/- 150 mm Hg.ml; I+, 745 +/- 191 (p less than .001); C2, 520 +/- 198; I-, 420 +/- 139 (p less than .001). We conclude that (1) neither Emax nor Vo are individually reliable indexes of changed contractility, and (2) the area beneath the ESPVR between defined end-systolic volume limits is a consistent indicator of variations in inotropic state. 相似文献