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41.
Eiji Takeuchi Yuji Nimura Shin-ichi Mizuno Hideaki Suzuki Shinsuke Iyomasa Masaki Terasaki Hiroshi Kuriki Keiko Tamiya-Koizumi Shonen Yoshida 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(3):254-262
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
42.
A rat model of monitoring liver allograft rejection 总被引:5,自引:0,他引:5
Timi Martelius Heikki Mäkisalo Krister Höckerstedt Eero Taskinen Irmeli Lautenschlager 《Transplant international》1997,10(2):103-108
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
43.
T. Scholz Ø. Mathisen A. Bergan S. Osnes R. Innes T. Pedersen A. O. Aasen O. Søreide 《Transplant international》1997,10(3):180-184
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
44.
在动物实验的基础上,比较了抗AFP单克隆抗体(mAb)和抗AFP多克隆抗体(pAb)两种不同抗体双弹头标记物在肝癌患者体内的生物代谢情况。结果显示,两种抗体标记物的血浆清除半衰期均在24h左右,mAb标记物的清除较pAb标记物略慢。尿清除的半衰期,mAb标记物约为120h,而pAb标记物则约为18h,表明二者的体内生物代谢不同,疗效可能不一。 相似文献
45.
Summary With the use of duplex Doppler ultrasound and color Doppler flow imaging(CDFI), the characteristics of blood supply in neoplasma
were studied in 51 cases of 60 liver tumors, and compared with the results of surgery, pathological examination and hepatic
anerial angiography. The result showed that: 1. Doppler blood flow signals could be detected in all hepatic carcinomas, and
in 10 cases of 18 hemangiomas, significant difference was observed (P<0.001); 2. Doppler blood flow spectra showed pulsatile pattern in 41 of 42 hepatic carcinomas, and in 6 of 10 hemangiomas
(P<0.01); and 3. the peak flow velocity was obviously lower in hemangioma group than in hepatic carcinoma group (20.34±23.93
vs 64.74±30.18 cm,P<0.001). The characteristics of CDFI show that hemangiomas and hepatocellular carcinomas are different. It can, therefore,
be concluded that the blood supply of hepatic carcinomas mainly comes from hepatic arterial system, and is of value in duplex
Doppler ultrasound and CDFI. 相似文献
46.
KYOSUKE YAMAMOTO NOBUHIRO FUKUDA LEI ZHANG TAKAHIRO SAKAI 《Pharmacological research》1996,33(6):337-342
The aim of this study was to examine the effects of dietary fenofibrate (0.05% in the diet) on ketone body production and lipid secretion in isolated perfused rat liver. Feeding with fenofibrate for 7–9 days caused an increased liver weight. Ketone body production was significantly greater in the livers perfused with oleic acid than in those perfused without fatty acid, with the elevation of the ratio ofβ-hydroxybutyrate:acetoacetate indicating an increased redox potential in mitochondrial compartments by exogenous fatty acid. On the other hand, fenofibrate feeding caused a further stimulation of ketone body production from both endogenous and exogenous fatty acid substrates, respectively, with a decreased ratio ofβ-hydroxybutyrate:acetoacetate as compared to respective control livers, indicating a decreased redox potential. Hepatic secretion of triglyceride, but not of cholesterol, was decreased markedly in the fenofibrate-fed rats, especially when oleate was provided, suggesting an inverse relationship between rates of ketogenesis and triglyceride secretion. These results suggest that the altered hepatic metabolism of long-chain fatty acids between oxidation and esterification caused by fenofibrate may thus be a factor responsible for the decreased secretion of triglyceride, hence leading to hypotriglyceridaemiain vivo. 相似文献
47.
大鼠肝细胞Ⅰ,Ⅲ型前胶原基因表达及PDGF的影响 总被引:3,自引:1,他引:2
目的观察大鼠肝细胞Ⅰ,Ⅲ型前胶原基因的表达及PDGF对其表达的影响.方法应用原位杂交技术检测分离培养的SD大鼠肝细胞(n=30)内Ⅰ,Ⅲ型前胶原基因的表达.同时观察10μg/L(n=30)和30μg/L(n=30)PDGF促进前胶原基因表达的作用.测定基因表达颗粒总面积占细胞总面积的百分比,并作比较分析.结果无论正常肝细胞或是在两种浓度的PDGF存在时,肝细胞内均可见到Ⅰ,Ⅲ型前胶原基因的表达.正常肝细胞Ⅰ,Ⅲ型前胶原基因表达面积的百分比(%)为77±19和75±21;加10μg/LPDGF后为115±19和112±10,而加30μg/L后为152±34及181±28,且在后者中表达明显增强(P<005及P<001).结论PDGF在转录水平上促进肝细胞胶原的合成. 相似文献
48.
49.
50.
生物人工肝和肝细胞移植技术需要建立肝细胞库以提供大量具有高度活性和良好功能的肝细胞.肝细胞冻存技术的研究成为实现这一目标的关键,而对冻存保护剂的研究则是肝细胞冻存技术取得突破的主要方向,此文就近些年来国内外肝细胞冻存领域中冻存保护剂的研究进展进行了综述. 相似文献