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41.
Between 4/1986 to 1/1989, 74 orthotopic liver transplantation were performed in 62 patients (62 first liver transplants, 10 as second graft and two as a third graft); 57 in adults and 17 in children. The main indication for the operation was liver cirrhosis (61.4%) (the most frequent etiology was alcoholic cirrhosis, 28.5%). Six cirrhotic patients had a hepatocarcinoma (9.6%). Two received a liver and kidney transplant due to terminal renal insufficiency and hemodialysis. The most frequent indication in children was biliary atresia (33.3%). Six patients had a fulminal liver failure (9.6%). AB0 blood group compatibility was identical in 87.5%, compatible in six and incompatible in three patients. Total orthotopic liver transplantation was performed in 67 patients, and size-reduced liver was indicated in 7 patients. Extracorporeal veno-venous bypass was used in adults but never in children. In 93.1% of the transplants a single hepatic artery was anastomosed to the recipient and in 6.9% a double anastomosis was performed. In 62.5% of the patients a end-to-end choledocho-choledochostomy was performed and in 34.8% hepatico-jejunostomy was indicated. Three months postoperative mortality rate was 12.9%. Arterial stenosis and thrombosis were the most frequent complication.  相似文献   
42.
To evaluate the effects of irradiation on heterotopically placed vascularized knee isografts, a single dose of 10 Gy of total-body irradiation was given to Lewis donor rats. Irradiation was delivered either 2 or 6 days prior to harvesting or subsequent transplantation, and evaluated at 1, 2, and 4 weeks after grafting. Irradiation caused endothelial depopulation of the graft artery, although vascular pedicle patency was maintained throughout the study. Bone graft viability and mineralization were normal. Dramatic changes in the bone marrow were seen that included an increase of its fat content (P less than 0.001), and a concomitant decrease in bone marrow-derived immunocompetent cells. These changes were more prominent in recipients of grafts from day -6 irradiated donor rats. Total-body irradiation did not prejudice the use of vascularized bone grafts, and exhibited an associated immunosuppresant effect over the vascular endothelium and bone marrow. This may be a further rational conditioning procedure to avoid recipient manipulation in vascularized bone allotransplantation.  相似文献   
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The initial poor absorption of the corn oil-based, gel capsule oral formulation of cyclosporin (CyA) greatly limits its use for inception of immunosuppressive therapy. Insufficient drug concentrations during the early post-transplant period predispose to renal allograft rejection. The present study served to compare the time required to achieve therapeutic CyA concentrations after de novo administration of the corn oil-based gel capsule (CyA-GC; n = 11) versus the microemulsion (CyA-ME; n = 11) formulation of CyA. During the 1st month after renal transplantation, patients underwent serial pharmacokinetic profiling from which we obtained observed and dose-corrected values of several parameters. Although patients in neither the CyA-GC nor the CyA-ME group adequately absorbed the drug during days 0–2, from day 3 to 4 patients in the CyA-ME group showed significantly greater absorption than those in the CyA-GC group (P = 0.041). Patients in the CyA-ME group reached the 1st month target average concentration (Cav) values ( ≥ 550 ng/ml) earlier than those in the CyA-GC group and required significantly lower daily CyA doses (P = 0.018). We conclude that therapeutic CyA levels can be achieved more rapidly and with lower doses of the drug after de novo administration of CyA-ME than with CyA-GC. Received: 13 September 1996 Accepted: 7 January 1997  相似文献   
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The neuropeptides neurotensin and neuromedin N (from 10−12 M to 10−9 M) have been showed in this study to stimulate significantly in vitro several steps of the phagocytic process: adherence to substrate, chemotaxis, ingestion of inert particles (latex beads) and production of superoxide anion measured by nitroblue tetrazolium reduction in resting peritoneal macrophages from BALB/c mice. A dose-response relationship was observed, with a maximal stimulation of the phagocytic process at 10−11 M. The two neuropeptides induced no change of intracellular cyclic AMP in murine macrophages. Moreover, adherence and chemotaxis decreased significantly in the presence of EGTA (1 mM), a chelator of extracellular Ca2+, or ryanodine (0.5 mM), a blocker of a Ca2+-gated channel from the endoplasmic reticulum, in both controls and samples with the addition of neurotensin or neuromedin N. These results suggest that there is no relation between the cAMP messenger system and the phagocytic process stimulation in murine peritoneal macrophages by neurotensin or neuromedin N. In addition, the results observed with EGTA and ryanodine could indicate that these two neuropeptides produce their effects through an increase of intracellular Ca2+ concentration.  相似文献   
47.
The author describes his surgical approach to the problems of the aging upper arm and elbow region. Surgery at an appropriate age can prevent the progressive wrinkling of the elbow which is further aggravated by aging of the upper arm. The author's operation is aimed at correcting both portions of the arm anatomy at the same time.  相似文献   
48.
Summary Nerve regeneration was studied in a model of centrocentral anastomosis (CCA) performed on the sciatic nerve of the rat. Experimental CCA was made by suturing the proximal end of the peroneal branch on the proximal end of the sural branch, placing between them a peroneal nerve graft (Group I, 20 rats) or a silicone chamber (Group II, 12 rats). Nerve grafts had a length of 5mm and silicone chambers 7 mm. In six silicone chambers an 1 mm nerve graft was placed in the centre of the tube. In group I animals anterograde degeneration was studied by cutting the graft 60 days after surgery. In group II, nerve regeneration was studied 2, 4 and 8 weeks after surgery. Results indicate that in CCA: 1) regenerated axons coming from one nerve end grow into the graft but do not cross the contralateral suture line; 2) regeneration is poorer in silicone chambers than in nerve grafts; and, 3) in silicone chambers regeneration is related to time. The reduction in the regenerative capability in CCA seems to be related to the alteration of nerve sprouts aiming for the peripheral targets.  相似文献   
49.
The course of the subscapular artery was studied in 20 rabbits. Its course was constant, giving two branches to the latissimus dorsi muscle after which the vessel sent a branch (S1) that perforated the panniculus carnosus to supply a large territory of skin. In a separate experiment, the contribution of the S1 branch to the viability of the rabbit latissimus dorsi musculocutaneous flap was evaluated. From this experiment it can be concluded that, first, it is possible in a rabbit to elevate a large skin flap based solely on a muscle perforator (S1), which survives completely. Second, in the rabbit latissimus dorsi musculocutaneous flap, S1 is the major blood supply to the skin component. Damage to it severely diminishes skin flap survival, even if the vascular supply to the underlying muscle is completely intact.  相似文献   
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