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991.
Our aim was to study the antioxidant and immunomodulatory effect of silibinin and vitamin E on the early postoperative course in rats that had undergone a partial hepatectomy (PHX). Male Wistar rats that were treated with silibinin (50 mg/b.w.kg i.p.) and/or vitamin E (500 mg/b.w.kg p.o.) were randomised to undergo 70% PHX. At 72 h after operation, Concanavalin A (Con-A) induced lymphocyte proliferation, and lipopolysaccharide (LPS) induced interleukin-1 (IL-1) mitogenicity and tumour necrosis factor-alpha (TNF-alpha) cytotoxicity were measured in the spleen. In addition, total free radical scavenger capacity of the liver was analysed. In PHX animals, Con-A induced lymphocyte proliferation was significantly decreased, and both LPS induced IL-1 and TNF-alpha activity were significantly increased as compared to Sham treated animals. Treatment with silibinin and vitamin E synergistically restored both lymphocyte proliferation (P<0.01) and cytokine activity (P<0.001) in PHX animals. In addition, silibinin and vitamin E synergistically (P<0.001) restored total hepatic free radical scavenger capacity as well as serum levels of AST and gammaGT, that were all markedly decreased in PHX animals. Our results suggest that preoperative treatment with silibinin and/or vitamin E modulates the cellular immunoresponse and restores impaired liver function following PHX, presumably through their antioxidant capacity. This may explain their beneficial effects on the postoperative course of liver repair.  相似文献   
992.
目的:观察新构建人胰岛素基因逆转录病毒表达载体(pM54)在Phoenix和HepG2等细胞的表达情况。方法:1)脂质体法转染pM54质粒进入pT67、Phoenix和3T3细胞系;2)用新构建质粒的父本质粒p54和pCMVβGal质粒做转染基因对照;3)制备转染后细胞培养拟逆转录病毒上清液;4)旋转感染Phoenix及HepG2细胞;5)ELISA法检测转染、感染后上清液INS含量。结果:ELISA法检测证实感染细胞培养上清液中含较高水平目的蛋白INS的表达。对照结果均为阴性。结论:人胰岛素基因逆转录病毒介导旋转感染Phoenix等细胞,目的蛋白INS获得了预期的表达。实验为基因治疗或基因结合干细胞治疗糖尿病的进一步相关研究提供了重要数据。  相似文献   
993.
1. Fast cyclic voltammetry at carbon fibre microelectrodes was used in rats anaesthetized with chloral hydrate to monitor dopamine release in the caudate and nucleus accumbens evoked by electrical stimulation of the median forebrain bundle. Stimulation trains (50 Hz sinusoidal current, 100 +/- 10 microA r.m.s., 2s duration) were repeated every 5 min throughout the experiment. 2. The actions of the dopamine agonists quinpirole, pergolide, SKF 38393, bromocriptine, (+)-3-(3-hydroxyphenyl)-N-n-propylpiperidine ((+)-3PPP) and (-)-3PPP were compared in the two nuclei. 3. Bromocriptine (10 mg kg-1, i.p.) did not affect release in either nucleus while SKF 38393 caused a fleeting decrease in limbic but not striatal dopamine release at a high dose (20 mg kg-1, i.p.). 4. Quinpirole and pergolide (both 1 mg kg-1, i.p.) decreased stimulated dopamine release in the nucleus accumbens while in the caudate the drugs each caused a transient, though not quite significant, elevation of stimulated dopamine release followed by decrease in release of the same magnitude as that seen in the nucleus accumbens. 5. The (-)-enantiomer of 3PPP (20 mg kg-1, i.p.), a partial agonist at the dopamine autoreceptor, increased stimulated dopamine release in both nuclei although the action in the caudate was larger and more prolonged. (+)-3PPP (20 mg kg-1, i.p.), a full agonist, decreased release in the nucleus accumbens. A small, transient and not significant increase in the caudate was followed by decreased release. 6. The results are interpreted as being evidence for differences in the dopamine autoreceptor in the two nuclei, possibly in the affinity state of the receptor in each nucleus.  相似文献   
994.
995.
Complications of transluminal angioplasty   总被引:14,自引:0,他引:14  
Four hundred fifty-three percutaneous transluminal angioplasties in 352 patients were reviewed to determine the frequency, distribution, and cause of complications. The primary success rate was 89% (81%-82% for renal and distal runoff vessels, 91%-95% for the iliofemoral arteries). Fifty-nine complications occurred in 53 patients, including 20 puncture site complications, the most frequent being hematoma. The most important angioplasty complication was acute occlusion of the arterial lumen attributed to acute thrombosis (2%). Subintimal passage of the guide wire/catheter (2%) may also cause luminal compromise. Arterial dissection following balloon dilatation (1%) and distal emboli (1.5%) were less important clinically, and vessel wall rupture was rare (0.4%). Complications were two to four times more frequent for renal and distal popliteal/tibial compared with iliofemoral angioplasties; the lower success and higher complication rates are attributed to greater technical difficulty and the increased importance of spasm. Operator experience and technical refinements play an important role in reducing occurrence of serious complications. The frequency and severity of angioplasty complications compare favorably with the alternative surgical procedure.  相似文献   
996.
Naidich  JB; Rackson  ME; Mossey  RT; Stein  HL 《Radiology》1986,160(3):653-657
Ureteral obstruction can lead to renal failure without involving detectable dilatation of the calyces, renal pelvis, or ureter proximal to the obstruction. This phenomenon was noted in seven patients who had clinical obstruction that we were not able to diagnose using computed tomography (CT) or ultrasonography (US). These patients underwent percutaneous nephrostomy (PCN), which resulted in brisk diuresis and improved renal function. We obtained an accompanying antegrade urogram in these cases, which demonstrated the level of obstruction and indicated that dilatation of the collecting system was minimal or not present. When obstructive uropathy is suspected, we believe it is essential to consider performing PCN to evaluate and potentially reverse renal failure, even when CT and US scanning do not demonstrate obstruction.  相似文献   
997.
Gale  ME 《Radiology》1986,161(3):635-639
The anterior portion of the diaphragm has three typical appearances on computed tomographic (CT) scans, depending on the cephalocaudal relation of the xiphoid to the central tendon of the diaphragm. The anterior diaphragm most often appears as a relatively smooth or slightly undulating soft-tissue curve, concave posteriorly and continuous across the midline with the lateral diaphragmatic arcs. In the next most frequent CT appearance, the diaphragmatic line is discontinuous in the midline. On each of these images, the muscular line diverges rather than converges as it approaches the anterior chest wall. Less commonly, the anterior portions of the diaphragm are imaged on CT not as a thin line but instead as a broad band with irregular, ill-defined, or angular margins. Occasionally, the anterior diaphragmatic muscle is not identified on CT because the muscle fibers are inseparable from adjacent structures, or are extremely short or even absent. An understanding of these anatomic variations permits the correct diagnosis of Morgagni hernias and explains previously described variants of plain radiographic configurations of pneumoperitoneum.  相似文献   
998.
Inflammation: imaging with Tc-99m HMPAO-labeled leukocytes   总被引:9,自引:0,他引:9  
Leukocytes labeled with technetium-99m hexamethylpropyleneamine oxime (HMPAO) were used in 100 patients: 32 with suspected inflammatory bowel disease, 17 with fever of unknown origin, 21 with suspected abdominal sepsis, 20 with suspected bone sepsis, seven with bronchiectasis, and three with recent myocardial infarction. The distribution of activity in patients subsequently shown not to have inflammatory bowel disease was similar to that previously described for indium-111-labeled leukocytes. However, in this study, activity was also seen in the kidneys and bladder and occasionally the gallbladder on both early (1-3 hours) and late (24 hours) views, and in the colon in late views. Migration of Tc-99m-labeled granulocytes was seen in inflammatory disease as early as 30 minutes after injection, while normal bowel activity was not seen before 4 hours. The sensitivity of Tc99m-labeled leukocytes in the detection of inflammation was 100%, the specificity was 95%.  相似文献   
999.
Biopsy of the right adrenal gland by the transhepatic approach   总被引:1,自引:0,他引:1  
  相似文献   
1000.
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