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51.
A single donor surgeon's experience procuring the livers from 132 donors is described. Thirty-seven grafts (28.9%) had hepatic
arterial anomalies, 19 (14.4%) of which required arterial reconstruction prior to transplantation. Of the 121 grafts evaluated
for early function, 103 grafts (85.2%) functioned well, whereas 14 grafts (11.6%) functioned poorly and 4 grafts (3.3%) failed
to function at all. The variables associated with less than optimal function of the graft consisted of donor age (P<0.05), duration of donor's stay in the intensive care unit (P<0.005), abnormal graft appearance (P<0.05), and such recipient problems as vascular thromboses during or immediately following transplantation (P<0.005). A new preservation fluid, University of Wisconsin solution, allowed safe and longer cold storage of the liver allograft
than did Euro-Collins' solution (P<0.0001). A parameter of liver allograft viability, which is simple and predictive of allograft function prior to the actual
transplant procedure, is urgently needed. 相似文献
52.
F. ANDREASEN U. H. ERIKSEN† S.-J. GUUL† L. P. NIELSEN† O. M. BECH B. DIAMANT§ O. KAHR P. BRUUN‡ O. J. HARTLING‡ S. HVIDT† 《European journal of clinical investigation》1993,23(4):234-239
Abstract. Eight patients with mild heart failure were treated in random order for 1 week with 2 mg bumethanide at 0800 and 1200 (treatment I) h, 1 mg bumethanide at 0800, 1200, 1800, 2200 (treatment 2) and 5 mg bendroflumethiazide at 0800 and 1800 (treatment 3) h. The 'quality of life' did not differ significantly between the three treatment periods. At the presumed trough of the diuretic effect the circulating blood volume was largest during treatment 1; it was 6.3% smaller during treatment 2 ( P< 0.02) and 6.7%) lower during treatment 3 (P<0.05). In comparison with treatment 1, the maximal increase in rate-pressure product during physical exercise was 24.6% higher in treatment 3. Compared with treatment 1 the area under the curve (AUC) for plasma lactate during physical exercise was 14% lower during treatment 2 (P<0.05) and 18% lower during treatment 3 (P<0.01). These findings suggest that the type of program for diuretic therapy influences the magnitude of inevitable diurnal fluctuations in body fluids, the ability of the heart to work and the ability of the body to adjust to the oxygen demand. 相似文献
53.
建立兔乳酸脱氢酶C4(LDH-C4)分离纯化的新方法,研究该酶的动力学特性。采用Blue Dexteran和Sepharose 4B交联制成Blue Dextran-Sephaqrose 4B染料配体亲和层析柱,结合QAE-Sephadex A450离子交换层析分离兔LDH-C4,以作图法测定该酶动力学数据。 相似文献
54.
55.
Anna Pizzirusso Patrizia Oliva Sabatino Maione Michele D’Amico Francesco Rossi L. Berrino 《Naunyn-Schmiedeberg's archives of pharmacology》1998,357(5):514-518
In order to evaluate the role played by vasopressin on pressor responses elicited by stimulation of the periaqueductal gray
(PAG) area by excitatory amino acids we carried out in vivo studies in genetically vasopressin deficient rats (Brattleboro).
Microinjections of l-glutamic acid (glutamate, 0.6 to 60 nmol/rat) or N-methyl-d-aspartic acid (NMDA, 0.07 to 7 nmol/rat)
into the PAG area of freely moving Brattleboro rats induced increases of arterial blood pressure values significantly lower
than those obtained in Long Evans rats (control) (glutamate in Brattleboro rats: from +2±1 mmHg to 16±3 mmHg; glutamate in
Long Evans rats: from +16±2 mmHg to +36±4 mmHg; NMDA in Brattleboro rats: from +5±2 mmHg to +34 ±8 mmHg; NMDA in Long Evans
rats: from +18±7 mmHg to 80±9 mmHg; n=5). Similarly, in anaesthetized Brattleboro rats (urethane 1.2 g/kg i.p.) pressor responses to NMDA microinjections (0.7
nmol/rat) into the PAG area were significantly lower than in Long Evans rats (controls) (+15±3 mmHg vs +24±4 mmHg). In Long
Evans rats NMDA injection also reversed blood pressure decrease induced by ganglionic blocker, hexamethonium and/or losartan
(3 mg/kg i.v.), an AT1 receptor antagonist. In Brattleboro rats, NMDA injection did not reverse blood pressure decreases induced
by hexamethonium (5 mg/kg i.v.). Moreover, hexamethonium induced blood pressure decrease was not reversed by acetylcholine
injection (137 nmol/rat) into the PAG area of anaesthetized Long Evans rats, but if injected before hexamethonium, acetylcholine
was able to increase blood pressure (+25±3 mmHg). Our results document: i) the importance of the PAG area in the control
of cardiovascular system; ii) the involvement of excitatory amino acids in the neural control of vasopressin release; iii)
the close relationship between glutamate and vasopressin in the central blood pressure regulation.
Received: 1 April 1997 / Accepted: 2 February 1998 相似文献
56.
D. D. Nghiem 《Transplant international》1995,8(5):411-413
In most cases, whole pancreaticoduodenal allograft vessels can be reconstructed using a segment of donor common iliac artery bifurcation. An alternative way to bridge the splenic artery and the superior mesenteric artery (SMA) is to use a short segment of distal SMA as an interposition graft, as described herein. 相似文献
57.
背景 冠心病属中医“胸痹心痛”范畴,其证候分布以血瘀证最为多见,与老年人相比,中青年血瘀证的发生率更高。本研究在团队前期研究基础上进行拓展,首次运用动脉弹性和血管内皮功能检测联合载脂蛋白比值诊断中青年冠心病血瘀证,旨在为早期发现中青年冠心病血瘀证提供新思路,也可为优化补充冠心病血瘀证的诊断标准提供参考。目的 探讨踝肱指数(ABI)、肱踝动脉脉搏波速度(baPWV)、血管舒张功能(FMD)联合载脂蛋白B与载脂蛋白A-1比值(apoB/apoA-1)与中青年冠心病血瘀证的关系及其预测价值。方法 选取2016年12月至2021年12月于中日友好医院中西医结合心脏内科住院治疗的中青年(<50岁)冠心病患者,并根据《冠心病血瘀证诊断标准》分为血瘀证组和非血瘀证组。收集患者首次冠状动脉造影前的ABI、baPWV、FMD和apoB/apoA-1等临床资料。采用多因素Logistic回归分析构建中青年冠心病患者血瘀证的预测模型,并采用受试者工作特征(ROC)曲线进行预测价值评价。结果 本研究共纳入中青年冠心病患者206例,其中血瘀证组127例,非血瘀证组79例。多因素Logistic回归分析结果... 相似文献
58.
Time-dependent morphological alterations of cold-stored small bowel in Euro-Collins and Ringer's lactate solutions 总被引:2,自引:0,他引:2
Small bowel is one of the organs that can in principle be transplanted. Optimum preservation of the organ is essential for the success of transplantation. The aim of the present study is the investigation of time-related morphological changes of rat small bowel during preservation in hypothermic Euro-Collins (EC) and Ringer's lactate (RL) solution using light microscopy and transmission electron microscopy to evaluate the integrity of intercellular complexes of mucosal epithelium, one of the tissues of the intestine that is most susceptible to ischemia. Small bowels were perfused with either EC, RL solution or physiological saline solution and were placed in the different preservation solutions at 4 degrees C for 0, 3, 6 and 12 h. The results of our study suggest that both preservation solutions are suitable for short-term preservation of the small bowel although RL solution is more effective than EC solution. However, we conclude that further improvement of preservation solutions and/or techniques are needed to perform long-term preservation. 相似文献
59.
Intimal hyperplasia and hemodynamic factors in arterial bypass and arteriovenous grafts: a review 总被引:3,自引:0,他引:3
Stenosis at the graft–vein junction caused by intimal hyperplasia (IH) is the major cause of failure of vascular access grafts used for hemodialysis. There is a strong relationship between hemodynamic factors and formation of IH. The hemodynamic pattern and the location of IH are different in arterial bypass grafts (ABGs) compared with arteriovenous grafts (AVGs). In an ABG, end-to-side anastomosis of the expanded polytetrafluoroethylene graft and artery produces hemodynamic changes around the junction. IH develops at the arterial floor and the toe and heel of the distal anastomosis. Low shear stress and oscillating shear forces at the arterial floor and the heel plus a high wall sheer stress (WSS) gradient at the toe probably promote IH development. Compliance mismatch between the graft and artery causes turbulence that may contribute to IH formation. The blood flow rate in AVGs is 5–10 times greater than that in ABGs. High flow causes turbulence that injures endothelial cells and eventually results in IH. The peak WSS in AVGs is about 6N/m2, much higher than that in ABGs. Excessively high WSS may effect IH formation in AVGs. Several venous cuff or patch anastomotic designs have been used in attempts to regulate hemodynamic factors in grafts. In ABGs, these designs appear to help decrease IH formation. In AVGs, however, they generally have not improved patency rates. In a high-flow system such as an AVG, more drastic changes in anastomotic design may be required. 相似文献
60.
The problem of synaptosome formation in the electric organ of Torpedo has been re-investigated using tissue from juvenile fish. This tissue is softer than adult material and can be easily homogenized in an Aldridge-type homogenizer. Homogenates so prepared contain a significant number of synaptosome-like structures which can be purified by differential and density gradient centrifugation. The purified particles are enriched in acetylcholine and choline acetyltransferase; they also contain lactate dehydrogenase activity, most of which is in an occluded form. The structure of these particles as revealed by electron microscopy is unusual in that they have no post-synaptic adhesions, relatively few synaptic vesicles and no intraterminal mitochondria. Because of their unusual morphology we have named these particles nerve terminal sacs (T-sacs). A high-affinity, hemicholinium-3 sensitive choline uptake system with an apparent Km of 1–3 μm is associated with the T-sacs. 相似文献