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1.
We have shown previously that the plant cannabinoid cannabidiol (CBD) elevates intracellular calcium levels in both cultured hippocampal neurones and glia. Here, we investigated whether the main psychotropic constituent of cannabis, Δ9-tetrahydrocannabinol (THC) alone or in combination with other cannabis constituents can cause similar responses, and whether THC affects the responses induced by CBD. Our experiments were performed with 1 μM pure THC (pTHC), with 1 μM pure CBD (pCBD), with a high-THC, low CBD cannabis extract (eTHC), with a high-CBD, low THC cannabis extract (eCBD), with a mixture of eTHC and eCBD (THC:CBD = 1:1) or with corresponding ‘mock extracts’ that contained only pTHC and pCBD mixed in the same proportion as in eTHC, eCBD or the 1:1 mixture of eTHC and eCBD.  相似文献   
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Isolated rat livers were perfused with an immunoglobulin-free fluid containing homologous rat erythrocytes suspended in an isotonic saline solution. Galactosamine hepatitis and alpha-naphthylisothiocyanate cholestasis were induced as experimental liver diseases. The glutamic oxalacetic transaminase (GOT) and guanosine triphosphate (GPT) activities, the potassium level as well as the redox quotients of lactate/pyruvate and beta-hydroxybutyrate/acetoacetate were determined as liver function parameters. Results: The same dose of galactosamine led to two different types of reaction. The group suffering more damage (rendering maximum GOT activities) phagocytosed significantly (p less than or equal to 0.05) more erythrocytes than the other group. Galactosamine hepatitis significantly slows down the phagocytosis of erythrocytes. The function of the mononuclear phagocytosing cells in the liver is intact. The alpha-naphthylisothiocyanate (ANIT) cholestasis significantly reduces the capacity of the mononuclear phagocytosing cells in the liver. Young erythrocytes were phagocytosed significantly better than old ones in either type of liver damage, in galactosamine hepatitis and in ANIT cholestasis as well as by healthy livers.  相似文献   
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Endothelial cell antigens recognized by xenoreactive human natural antibodies.   总被引:10,自引:0,他引:10  
Hyperacute rejection of vascularized, discordant xenografts is generally though to be initiated when natural antibodies of the recipient bind to endothelial cells of the donor organ. While rejection of such xenografts always occurs, the molecular targets of natural antibodies have not been elucidated. The aim of the experiments reported herein was to identify the molecules on porcine endothelial cells that would be recognized by human natural antibodies if a porcine organ were to be transplanted into a human (or rhesus). Toward the end, it was shown that the major components recognized by human serum on porcine endothelial cells are glycoproteins of 115kDa, 125kDa, and 135kDa (gp115/135). Reactivity with these glycoproteins was abrogated by enzymatic cleavage of N-linked oligosaccharides or of subterminal beta-D-gal residues suggesting that the determinants are located on oligosaccharides rather than on the polypeptide cores. The biological relevance of gp115/135 was suggested by experiments in which a similar series of components was shown to be recognized by rhesus natural antibodies and by the absorption of such antibodies by perfusion of porcine kidneys. The gp115/135 antigens were present on porcine platelets but not porcine RBC or lymphocytes. Nevertheless, purified RBC and lymphocytes absorbed human anti-gp115/135, suggesting that human natural antibodies recognize the same or crossreactive carbohydrate determinants expressed on the surface of a variety of cells.  相似文献   
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A case of sinusoidal fetal heart rate pattern occurred in association with postdate pregnancy and face presentation. The case met the criteria for sinusoidal pattern established by Modanlou and Freeman except for a prior period of reactivity. Prompt recognition and action precluded the potential adverse outcome associated with this tracing.  相似文献   
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A randomised double blind placebo controlled trial is the most reliable method of assessing putative new developments in medical treatment. In schizophrenia, however, some clinicians believe that relapse contributes to long term deterioration and therefore that patients exposed to either placebo or an inactive new treatment may be put at a disadvantage in the long run if the trial leads to an additional relapse. A seven year follow up of patients included in a randomised placebo controlled trial of fluphenazine decanoate, in which 66% of the group given placebo relapsed compared with 8% of those who received the active drug, permitted examination of any long term adverse consequences in those patients who had received placebo. Seventy six (94%) of the 81 patients in the original trial were followed up. At the end of the follow up period there were no consistent or important differences in any measure of clinical or social outcome between the patients who had received placebo and those who had received the active drug. This negative finding has implications for the debate on the risk of placebo controlled trials of maintenance treatment in chronic schizophrenia.  相似文献   
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硫酸多糖对体外人脐静脉内皮细胞损伤的保护作用   总被引:8,自引:1,他引:7  
研究表明,硫酸多糖体外对多聚阳离子和氧自由基损伤的人脐静脉内皮细胞有保护作用。肝素、硫酸软骨素A抗多聚阳离子损伤作用比同浓度低分子肝素和甘糖酯强。肝素、硫酸软骨素A、甘糖酯抗氧自由基损伤作用优于同浓度低分子肝素。结果显示硫酸多糖有保护血管内皮的作用,其作用可能与所带阴离子基团有关。  相似文献   
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Ixodes dammini Spielman, Clifford, Piesman & Corwin collected from a study site in southwestern Wisconsin were examined for Borrelia burgdorferi infection. Adult spirochete infection rates varied seasonally (38.1%, spring 1990; 60.3%, fall 1990; 41.2%, spring 1991) and were similar to or higher than rates reported in various studies from the northeastern United States. Statistical comparison of seasonal infection rates indicated a significant difference between the fall 1990 adult population and the subsequent overwintered population of the same cohort (spring 1991). Additionally, a significant decrease in the intensity of spirochete infection was observed in the overwintered adult sample.  相似文献   
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