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101.
金丹肝泰1号对大鼠急性肝损伤防治作用的实验研究   总被引:2,自引:0,他引:2  
用D-氨基半乳糖(D-GaIN)制备大鼠急性肝损伤模型。方法:检测血清丙氨酸氨基转氨酶(ALT)和血清天门冬氨酸氨基转氨酶(AST)的活性,观察光镜下肝组织的病理学改变,探讨对急性肝损伤的保护作用。结果:口服浸膏可显降低急性肝损伤大鼠血清ALT和AST水平,减轻肝细胞的变性坏死,其作用强度与肝炎宁相当,但弱于联苯双酯。  相似文献   
102.
Hepatocyte regeneration has been widely investigated, with the mitotic index and the incorporation of [3H]thymidine being used as regeneration markers. We focused on the induction of DNA replication enzymes, particularly DNA polymerases (pol) α, δ, and ε. Using rat models, we have shown that the activity of pol α in crude liver extract well represents the regenerating capacity of hepatocytes. Using pol α as an indicator, we analyzed liver regeneration in rat models under various conditions: obstructive jaundice, external or internal biliary drainage, and the obstruction of portal vein branches. It has been revealed that the ligation of the common bile duct alone induces a certain amount of hepatocyte proliferation. It was striking that external biliary drainage suppressed regeneration capacity in cholestatic rat liver after partial hepatectomy. The strong regeneration in nonligated lobes induced by portal branch ligation was similar to the liver regeneration seen after partial hepatectomy with respect to the induction of DNA polymerases. Taken together, the aspects of DNA replication, particularly the induction of DNA polymerases, may contribute to shedding new light on the regeneration of human liver. This work was supported in part by a Grant-in-Aid for General Scientific Research and for Cancer Research from the Ministry of Education, Science and Culture, Japan, and by grants from the Uehara Memorial Foundation  相似文献   
103.
It is well known that hepatitis C virus (HCV)-related chronic liver disease may be associated with various immunological disorders including mixed cryoglobulinemia, which is accompanied by cutaneous vasculitis, arthralgias, membranoproliferative glomerulonephritis, and neuropathy in association with cryoprecipitable immune complexes in serum. We describe here the first case of central nervous system HCV infection with evidence of the virus in the cerebrospinal fluid in association with cryoglobulinemia in a patient who developed recurrent episodes of papillitis and vasculitis of the arteria spinalis anterior after liver transplantation. Received: 3 September 1996 Received after revision: 13 November 1996 Accepted: 6 December 1996  相似文献   
104.
A rat model of monitoring liver allograft rejection   总被引:5,自引:0,他引:5  
Rat models are often used to study liver allograft rejection. We have established a model for rat liver allograft rejection, monitored by fine needle aspiration biopsy (FNAB), in the strain combination PVG-to-BN with a mean survival time of 37 ± 20 days. In this model, we observed acute rejection with an intense peak of lymphoid blasts and lymphocyte-dominated inflammation in the FNAB [9.1 ± 3.0 corrected increment units (CIU)], and an eventual increase in macrophages (up to 4.2 ± 4.4 CIU), together with fibrosis and parenchymal necrosis in the graft. Markers of immune activation, such as an increase in IL-2-receptor (from 1 % ± 2 % to 21 % ± 13 %) and class II (from 20 % ± 9 % to 43 % ± 13 %) expressing lymphoid cells and induction of ICAM-1 in the graft, were consistent with the overall cellular response. The FNAB correlated well with parallel graft histology. In this rat model, the atraumatic monitoring makes a close follow-up possible without having to sacrifice the experimental animals. This saves work, animals, and costs in the study of liver rejection. Received: 2 July 1996 Accepted: 28 October 1996  相似文献   
105.
Pediatric liver transplant recipients constitute a population characterized by a particularly unpredictable and poor bioavailability of cyclosporin (CyA). Even though several adult studies show that the new oral formulation of CyA, Neoral (NEO), produces better bioavailability and blood level predictability, few data describe its pharmacokinetics in children. We performed a complete analysis of the pharmacokinetics of NEO in ten small children after primary liver transplantation. Three pharmacokinetic profiles were set up with data obtained from tests taken during i. v. administration of CyA, after the first oral NEO dose, and after the last NEO dose before discharge from the hospital. The mean half-lives obtained were 8.1, 7.7, and 6.9 h, respectively, and the bioavailabilities were 22 % and 21 % for the first and last NEO doses. A large interpatient variability was observed. This was due, in part, to episodes of diarrhea that interfered with the pharmacokinetic evaluation and, in part, to the variability of post-transplant hepatic function. There was a good correlation between CyA trough levels and their related AUCs for both NEO profiles (r = 0.93 and r = 0.74, respectively). We conclude that, even though the pediatric OLT population remains more unpredictable than that of adults, NEO has a relatively rapid half-life and a remarkably improved bioavailability. Received: 29 November 1996 Received after revision: 10 April 1997 Accepted: 15 May 1997  相似文献   
106.
We report on the successful regrafting of a transplanted liver. The donor liver was first grafted into a patient suffering from cryptogenic cirrhosis; the patient died 1 day after the elective transplantation of cerebral bleeding. The well-functioning graft was harvested again and transferred to our institution. After another 12 h of cold ischemia, the liver was reperfused in an urgently registered patient with recurrence of hepatitis B in his first graft. The transplantation was successfully performed and the patient is now doing well, more than 5 months after regrafting with the reused liver. Received: 21 October 1996 Received after revision: 9 January 1997 Accepted: 27 January 1997  相似文献   
107.
We have introduced and evaluated several modifications of the conventional venovenous bypass (VVBP) in 29 adult patients undergoing liver transplantation (OLT). A percutaneous technique for insertion of a jugular venous return cannula and a femoral vein cannula was applied. The inferior mesenteric vein (IMV) was used for splanchnic decompression, which facilitated dissection of the recipient liver and allowed portal anastomosis to be performed without disconnecting the portal bypass. A heat exchanger was introduced into the bypass circuit to prevent heat loss. The percutaneous technique prevented complications related to dissection in the axilla and groin. Hemodynamic characteristics corresponded to those found using the traditional technique. Complications related to the VVBP were seen in only one patient in whom the femoral catheter was accidentally introduced into the femoral artery. We conclude that percutaneous cannulas, use of the IMV for splanchnic decompression and the introduction of a heat exchanger offer significant benefits and that they are safe and reliable. Received: 23 August 1996 Received after revision: 14 January 1997 Accepted: 27 January 1997  相似文献   
108.
Abstract One hundred eighty-one consecutive patients with fulminant hepatic failure (FHF) presenting in a 2-year period were reviewed. In this cohort we examined the impact of pretransplant renal failure on mortality and morbidity following orthotopic liver transplantation (OLTx). Twenty-seven patients (18 female, 9 male) with a median age of 43.5 years (range 19–65 years) underwent OLTx. FHF was due to idiosyncratic drug reaction ( n = 4), paracetamol overdose ( n = 3), seronegative hepatitis ( n = 17), hepatitis B ( n = 1), veno-occlusive disease ( n = 1), and Wilson's disease ( n = 1). Renal failure was present in 14 patients, 7 of whom died (whereas there was 100 % survival in patients without renal failure). Pretransplant renal failure was associated with prolonged mechanical ventilation (13 days vs 6 days, P = 0.05), prolonged intensive care stay (17 days vs 8 days, P - 0.01) and prolonged hospital stay (27 vs 21 days, P = NS). Pretransplant renal failure did not predict renal dysfunction at 1 year after OLTx. We conclude that the survival of patients transplanted for FHF is inferior to that of patients transplanted for chronic liver disease (67 % vs 88 % 1-year survival in Birmingham). For patients with FHF undergoing transplantation, pretransplant renal failure strongly predicts poor outcome with significantly greater consumption of resources.  相似文献   
109.
Alcohol consumption during pregnancy is teratogenic and induces severe alterations in hepatocytes. In the hepatocyte peroxisomal system, ethanol is converted in the presence of H2O2 to acetaldehyde and water. Therefore, peroxisomal catalase also acts as an antioxidant defence mechanism by removing H2O2 and preventing the formation of hydroxyl radicals in the cell. Alterations in peroxisomal catalase after pre- and pre+postnatal alcohol exposure were investigated in the rat. The effect of pre- and postnatal exposure to ethanol on hepatocyte subpopulations was analysed in isolated hepatocytes originating from periportal, intermediate and perivenous zones. Analysis of catalase revealed that the total activity and content of this enzyme were higher in 12-day-old cells than in cells from newborns and that this increment was more pronounced in treated cells. In controls, the amount of peroxisomal catalase increased mainly in periportal cells, whereas alcohol exposure induced a significant increase in the catalase of perivenous hepatocytes. We conclude that pre- and postnatal alcohol exposure mainly affects the perivenous hepatocyte peroxisomes and that the increase in peroxisomal catalase could constitute a defence mechanism against free radical generation induced by alcohol exposure during the perinatal period.  相似文献   
110.
应用国产ELISA试剂盒对157例肝癌、肝硬化病人血清中抗-HCV及HBV-M进行检测,101例肝癌10例抗-HCV阳性,阳性率为9.9%;56例肝硬化6例抗-HCV阳性,阳性率为10.7%;肝癌组抗HCV与HBsAg双阳性率79%(8/101),HBsAg阳性率为723%(73/101),明显高于HCV感染率,说明HBV仍是乙肝流行地区的主要相关因素。14例抗-HCV阳性(包括可疑阳性),肝癌外周血中8例(57.1%)HBsAg阳性,推测HCV可单独作用但更常与HBV形成混合感染参与慢性肝病的癌变过程。  相似文献   
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