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101.
The clinical potential of tumor therapies must be evaluated using animal models closely resembling human cancers. We investigated the impact of locally delivered interferon-gamma (IFN-gamma) on primary hepatocarcinoma spontaneously developed by T-SV40 transgenic mice. A single intratumor injection of adenovirus IFN-gamma was sufficient enough to induce in vivo production of biologically active IFN-gamma, as assessed by STAT1 activation. IFN-gamma secretion led to the regression of primary tumor, principally by apoptosis of tumor hepatocytes. The lack of T-cells infiltrates in the liver upon treatment excluded a role of a specific immune response. In contrast, indirect pathways may include tumoricidal function of macrophages. Indeed, they were massively recruited in the entire liver under IFN-gamma treatment; transmigration through hepatic blood vessels could be observed and co-localization with damaged hepatocytes was obvious. This correlated with nonparenchymal liver cell iNOS expression and high level of NO in hepatic extracts. Moreover, in vitro experiments showed that NO releasing agents induced cell death of freshly isolated tumor hepatocytes, suggesting that NO could be one of the major effector molecules. Altogether, these observations defined an important role of IFN-gamma in controlling tumor development in a model of primary hepatocarcinoma.  相似文献   
102.
高效液相色谱法测定寒痹停片中士的宁含量   总被引:6,自引:0,他引:6  
目的:建立用HPLC测定寒痹停片中士的含量的方法。方法:氰基柱;流动相-甲醇-水-三乙胺-乙酸(9800:155:15:30);紫外检测波长254nm。结果:在4~20ug/ml范围内,标准曲线回归方程为:Y=-2803+8967x(r=0.9997),RSD=1.65%?加样回收率的平均值为99.82%。结论:实验表明,这是一个适用于生产控制和产品质量检验的简单、快速、准确的方法。  相似文献   
103.
1. The NHE1 isoform of the Na(+)/H(+) exchanger plays an important role in the regulation of intracellular pH and in cardiac cell injury caused by ischaemia and reperfusion. SL 59.1227 is a novel imidazolypiperidine Na(+)/H(+) antiport inhibitor which is structurally unrelated to previously described acylguanidine inhibitors such as cariporide. 2. Recovery of pH(i) following an intracellular acid load was measured in CCL39-derived PS120 variant cells, selectively expressing either NHE1 or NHE2 isoforms of the Na(+)/H(+) exchanger. pH(i) recovery was potently and selectively slowed by SL 59.1227 in NHE1-expressing cells (IC(50) 3.3+/-1.3 nM) versus NHE2-expressing cells (2.3+/-1.0 microM). The respective IC(50) values for cariporide were 103+/-28 nM (NHE1) and 73+/-46 microM (NHE2). 3. In anaesthetized rats following left coronary artery occlusion (7 min) and reperfusion (10 min) SL 59.1227 (10 - 100 microg kg(-1) min(-1) i.v.) inhibited ischaemia-mediated ventricular tachycardia (71 - 100%) and reperfusion-induced ventricular fibrillation (75 - 87%) and prevented mortality. Bolus i.v. administration of SL 59.1227 (1 mg kg(-1)) produced anti-arrhythmic effects when administered either before or during ischaemia. 4. Cardiac infarct size was determined in anaesthetized rabbits following left coronary artery occlusion (30 min) and reperfusion (120 min). Infarct size measured as a percentage of the area at risk was 36.2+/-3.4% (control group) versus 15.3+/-3.9% (SL 59.1227 0.6 mg kg(-1) i.v.). 5. SL 59.1227 is the first example of a potent and NHE1-selective non-acylguanidine Na(+)/H(+) exchanger inhibitor. It possesses marked cardioprotective properties.  相似文献   
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Summary Varus deformity of the knee is common in young children who have suffered from fulminating purpura. This study was directed at the anatomic features of the vascularisation of the upper end of the tibia that might account for such deformation. It was based on the dissection of 28 anatomic specimens prepared by injection of Indian ink into the vascular trunk. 16 specimens were diaphanised for better analysis of the intracartilaginous distribution of the vessels. The study showed that the vascularisation of the medial condyle of the tibia is poor and of terminal nature, which may explain the occurrence of ischemic growth disorders following fulminating purpura.
Etude de la vascularisation artérielle du condyle médial du tibia chez le foetus
Résumé Les déformations en varus du genou chez les jeunes enfants ayant présenté un purpura fulminans sont fréquentes. Ce travail a pour objet de rechercher les caractéristiques anatomiques de la vascularisation de l'extrémité supérieure du tibia qui peuvent expliquer ces déformations. L'étude porte sur la dissection de 28 pièces anatomiques préparées par injection de l'axe vasculaire à l'encre de Chine. Pour mieux analyser la répartition intra-cartilagineuse des vaisseaux, 16 pièces ont été diaphanisées. Cette étude montre que la vascularisation du condyle médial du tibia est pauvre, de type terminal, ce qui peut expliquer la survenue de troubles de croissance ischémiques dans les suites d'un purpura fulminans.
  相似文献   
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107.
G Guilbaud  M Peschanski  A Briand  M Gautron 《Pain》1986,26(3):301-312
The spinal ascending pathways responsible for neuronal ventrobasal (VB) thalamic responses elicited by joint stimulation of the posterior paw were determined in arthritic rats used as a model of experimental pain. Responses of a same neurone to mechanical (movement--pressure--brushing) or thermal stimulation (50 degrees C) were analysed before and after discrete lesions in the white matter of the spinal cord. For 6 neurones responding exclusively to brushing applied on a small receptive field (RF) strictly contralateral to the recording site, responses were not altered as long as the contralateral dorsal column was intact. Twenty neurones exhibited bilateral symmetrical RF located on the posterior paws including the ankles and for some units the digits. They were driven by moderate pressure and/or mild sustained joint movement and by immersion in a hot water bath at 50 degrees C. Their responses were not significantly modified when the lesions destroyed most of the dorsal and the dorsolateral parts of the spinal cord. In 16/20 cases effect of one hemisection of the cord was studied: when the hemisection was contralateral to the recording site (n = 8) VB neuronal responses elicited from the paw ipsilateral to this side were eliminated in 6/8 cases; when the 1/2 section was ipsilateral to the recording site (n = 8) the lesion induced the elimination of the responses elicited from the paw opposite to the recorded VB for one unit only. The involvement of the spino-reticular pathways which have not only a crossed but also a non-crossed component is suggested. This hypothesis is discussed by comparison to data previously obtained, showing that by contrast in healthy rats the spino-thalamic tract is essential for VB neuronal responses to noxious stimuli.  相似文献   
108.
为探讨体外循环(CPB)导致心脏植物神经系统(CAS)损伤的机理,了解温血心停跳液能否防止CPB后心率变异性(HRV)的降低,采用对照方法观察了温血心停跳液与冷晶体心停跳液对狗HRV的影响。结果显示:CPB后温血心停跳液组(WB组)和冷晶体心停跳液组(CC组)的全频谱(TP)、低频(LF)和高频(HF)均较术前明显降低(P<0.05),而且CC组比WB组降低更明显(P<0.05),但LF/HF在组内及组间均无明显变化(P>0.05)。CPB后24小时平均心率(MHR)明显增加(P<0.05),且CC组高于WB组(P<0.05)。本研究表明:采用温血心停跳液或冷晶体心停跳液的CPB不会干扰CAS平衡,但均能使HRV降低,温血心停跳液不能防止HRV损害。  相似文献   
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