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91.
Tolerance induction remains challenging following liver transplantation and the long-term use of immunosuppressants, especially calcineurin inhibitors, leads to serious complications. We aimed to test an alternative immunosuppressant, a chimeric anti-ICAM-1 monoclonal antibody, MD-3, for improving the outcomes of liver transplantation. We used a rhesus macaque liver transplantation model and monkeys were divided into three groups: no immunosuppression (n = 2), conventional immunosuppression (n = 4), and MD-3 (n = 5). Without immunosuppression, liver allografts failed within a week by acute rejection. Sixteen-week-long conventional immunosuppression that consisted of prednisolone, tacrolimus, and an mTOR inhibitor prolonged liver allograft survival; however, recipients died of acute T cell–mediated rejection (day 52), chronic rejection (days 62 and 66), or adverse effects of mTOR inhibitor (day 32). In contrast, 12-week-long MD-3 therapy with transient conventional immunosuppression in the MD-3 group significantly prolonged the survival of liver allograft recipients (5, 96, 216, 412, 730 days; p = .0483). MD-3 effectively suppressed intragraft inflammatory cell infiltration, anti-donor T cell responses, and donor-specific antibody with intact anti-cytomegalovirus antibody responses. However, this regimen ended in chronic rejection. In conclusion, short-term therapy with MD-3 markedly improved liver allograft survival to 2 years without maintenance of immunosuppressant. MD-3 is therefore a promising immune-modulating agent for liver transplantation.  相似文献   
92.
目的研究正常昆明小鼠胰腺导管上皮样细胞向胰岛样细胞分化的诱导条件。方法取正常成年昆明小鼠胰腺导管上皮进行原代培养,利用细胞贴壁时间的差异在培养24、48、72 h连续换液除去腺体细胞,在含2%胎牛血清的培养条件下除去成纤维细胞,使可以在无血清培养基中生长的胰腺导管上皮样细胞形成优势生长。在此条件下培养并传代。取第三代细胞以无血清诱导培养基促使其分化。取诱导后3、5、7、14 d的细胞进行免疫细胞化学染色鉴定。ELISA检测诱导生成的胰岛样细胞在高糖刺激下分泌胰岛素的功能。结果经过无血清诱导培养基诱导7 d后,胰腺导管上皮样细胞开始向胰岛素分泌细胞分化,胰岛素抗体染色阳性。14 d胰岛素抗体染色阳性细胞明显增多。该细胞在高糖刺激下可以分泌胰岛素。结论昆明小鼠胰腺导管上皮样细胞经过无血清培养基诱导可以向胰岛样细胞方向分化。并且该胰岛样细胞在高糖刺激下具有分泌胰岛素的功能。  相似文献   
93.
本文观察到腺苷脱氨酶抑制剂EHNA对离体灌流大鼠心脏氧反常性损伤有明显的作用,此外还发现在缺氧期(无氧灌流30分钟)EHNA也表现出明显的保护作用,心脏收缩幅度的降低和静息张力的升高均显著低于对照组。表明在缺氧期也可能有自由基的产生。  相似文献   
94.
Research Institute of Transplantology and Artificial Organs, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 110, No. 12, pp. 650–653, December, 1990.  相似文献   
95.
96.
Summary We studied the functional role of angiotensin II (AII) receptor subtypes and vasodilatory endothelial autacoid release in response to AII in isolated perfused rabbit hearts. AII infusion induced biphasic changes in coronary perfusion pressure (CPP): an initial increase was followed by a decrease until a plateau was reached. At higher concentrations of AII (10 nmol/l) this plateau phase was lower than the initial CPP level. AII infusion elicited inverse changes in peak left ventricular pressure (LVP): coronary constriction was associated with a transient decline, and during the plateau phase LVP was clearly increased. AII also moderately augmented prostacyclin (PGI2) release from the coronary vascular bed. The AII-induced changes in CPP, LVP, and PGI2 release were effectively inhibited by the AT1 receptor subtype antagonist ICI D8731 (30 nmol/l), but not by the AT2 receptor antagonist CGP 42112 (30 nmol/l). The adenosine A1 receptor antagonist 8-phenyltheophylline (0.1 mol/l) attenuated the decline in CPP following the constriction phase without affecting the changes in LVP during AII infusion. The cyclooxygenase inhibitor diclofenac (1 mmol/l) had no effect on the AII-induced changes in CPP, whereas the nitric oxide-synthase inhibitor NG-nitro-L-arginine (30 mol/l) markedly potentiated the vasoconstriction but was without effect on the plateau phase of the response. In contrast to AII, the thromboxane analogue U46619 elicited sustained increases in CPP which were associated with slight decreases in LVP.In conclusion, AII induced a biphasic pressor response in the rabbit coronary vascular bed consisting of a transient vasoconstriction followed by a dilatation especially at higher concentrations of AII, an effect which was independent of the endothelial autacoids nitric oxide and PGI2. The AII-induced dilatation probably reflected rapid desensitization of the coronary arterial smooth muscle to the constrictor effect, and the concomitant accumulation of vasodilatory metabolites such as adenosine, generated during the positive inotropic action of AII. All the effects of AII in the rabbit heart appeared to be mediated via the AT, receptor subtype localized on coronary endothelial and smooth muscle cells, as well as on cardiomyocytes.On leave from the Department of Biomedical Sciences, University of Tampere, P.O. Box 607, FIN-33101 Tampere, FinlandCorrespondence to: I. Pörsti  相似文献   
97.
应用B超对168例施行肝动脉导管栓塞(TAE)治疗的肝癌患者进行了胆囊、胰腺和脾脏的动态观察,并对其中有明显上腹部疼痛的34例进行了胃镜对照检查。结果发现TAE后胆囊病变最常见(123/168),占73.2%;其次为胃、十二指肠病变,占15.5%(26/168);胰腺病变为1.2%(2/168);未见脾脏病变。结果表明TAE后的消化系统并发症并非少见。  相似文献   
98.
Summary Esorubicin (4 deoxydoxorubicin) is a new analogue of the anthracycline, doxorubicin. This compound lacks the hydroxyl group at 4 position on the amino sugar of the anthracycline. Phase II study was designed to determine the clinical response rate and to define the qualitative and quantitative toxicities of esorubicin in patients with adenocarcinoma of the pancreas. Fifty-eight patients with inoperable adenocarcinoma of the pancreas were entered on the study, 47 were evaluable for response, and 57 were evaluable for toxicity. The dose of esorubicin was 30 mg/m2 for good risk patients and 25 mg/m2 for poor risk patients every 21 days and administered IV push through a side arm of a running IV. Diphenhydramine, 50 mg is administered IM prior to the administration of the drug to block local venous reaction. Subsequent doses of esorubicin were modified according to granulocyte and platelet nadirs and the drug was not administered until recovery of platelets (> 100,000/ul) and wbc (> 3000/ul). Three partial responses, 20 stable, and 31 with increased disease were observed. Forty-seven had severe granulocytopenia (< 250), and two patients had severe thrombocytopenia (< 25,000). One patient experienced a decrease in left ventricular ejection fraction with a total dose of 180 mg/m2. The dose of esorubicin in this study demonstrated that the drug has minimal activity in adenocarcinoma of the pancreas but the toxicity is tolerable. Search should continue for single agents with activity in this disease.  相似文献   
99.
The effect of tertiary basic drugs on mitochondrial MAO activity and the effect of MAO inhibitors (MAOIs) on basic drug accumulation in the isolated perfused rat lung were studied to clarify the role of MAO in drug binding to lung tissue. In the perfused lung preparation, the inhibition of MAO by basic drugs correlated well with their lipid solubilities and followed competitive kinetics. The inhibitory rank order (imipramine diphenhydramine > quinine > metoclopramide > procainamide) also correlated with their accumulation in the perfused lung. Moreover, MAOI treatment decreased the accumulation of basic drugs in the lung, and the potency of MAOIs to inhibit drug accumulation in the lung correlated with their MAO inhibitory activity. These results indicate that lung MAO has specific binding sites for basic drugs and may function as a drug reservoir.  相似文献   
100.
胰肾联合移植长期存活的临床研究(附5例报告)   总被引:6,自引:3,他引:3  
目的 提高糖尿病、糖尿病肾病患者的生活质量,方法 于1998-12/2000-01对5例糖尿病、糖尿病肾病患者施行了胰肾联合移植术,结果 5例患者肾功能恢复正常;其中2例患者分别于8wk,23wk发生急性排斥反应一次,经抗排斥治疗后逆转,2例术后2wk发生纯红再障(pure red cell aplasia,PRCA),1例手术后第15日供胰动脉血栓形成,切除胰腺,经1a以上观察,4例患者健康存活,胰肾功能良好。结论 胰肾联合移植是目前治疗糖尿病、糖尿病肾病最有效的手段。  相似文献   
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