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Ganoderma sinensis has been used widely in Oriental countries for the prevention and treatment of various diseases including cancer. Previous studies have shown that the lipid extract from Ganoderma exhibits direct cytotoxicity against tumor cells. Here, it is reported that the lipid extract from germinating G. sinensis spores, at lower concentrations that have no direct tumoricidal activity, induce potent antitumor immune responses in human monocytes/macrophages. Upon stimulation with the lipid extract, monocytes/macrophages exhibited markedly increased production of proinflammatory cytokines and surface expression of costimulatory molecules. Conditioned medium from stimulated cells effectively suppressed the growth of tumor cells. Apparently, the lipid extract triggered macrophage activation via a mechanism different from that associated with LPS. Moreover, it was observed that the lipid extract could partially re‐establish the antitumor activity of the immunosuppressive tumor‐associated macrophages. These results indicated that in addition to its direct tumoricidal activity, the lipid extract from G. sinensis spores could exert antitumor activity by stimulating the activation of human monocytes/macrophages. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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The effects of intracerebroventricularly (i.c.v.) administered gamma-glutamylcysteine (gamma-GC) and glutathione (GSH) monoethyl ester, subcutaneously (s.c.) injected L-2-oxo-4-thiazolidinecarboxylic acid (OTC) and intraperitoneally (i.p.) administered cysteine on the concentration of GSH in rat brain were investigated. The brain content of GSH, cysteine and gamma-GC was determined by HPLC with electrochemical detection (gold/mercury electrode) using N-acetylcysteine as internal standard. A dose-dependent increase in the GSH concentration (145-170% of controls) was found in the substantia nigra (SN) and in the rest of the brain stem after injection of gamma-GC, whereas no significant alterations in GSH were observed in the striatum and in the cerebral cortex. High levels of gamma-GC could be detected in the brain tissue after the administration, and the concentration of cysteine did also increase markedly after gamma-GC injection in all brain regions assessed. I.c.v. administration of L-buthionine sulfoximine (L-BSO) reduced the brain concentration of GSH by 50-70% within 24 hr. Injection of gamma-GC 24 hr after L-BSO resulted in an increase in GSH up to control values within 1-3 hr in the SN and the rest of the brain stem, whereas only a slight increase in GSH was observed in the striatum and the cerebral cortex. The concentration of GSH in the striatum and SN did not change after i.p. injection of cysteine, but a slight increase in the GSH concentration in the limbic region was observed. GSH monoethyl ester (i.c.v.) and OTC (s.c.) did not produce any significant increase in the GSH concentration in the brain. When the GSH concentration had been reduced by administration of L-BSO (i.c.v.; 24 hr) subsequent injection of GSH monoethyl ester led to a slight increase in the striatal and limbic GSH levels. These data show that, of the drugs studied, gamma-GC was the most effective in increasing brain GSH. It could thus serve as a valuable tool in future studies regarding metabolism and function of GSH in the brain. The observed difference in the effects of gamma-GC in different brain regions indicate that the brain tissue is not homogeneous with regard to GSH synthesizing capacity.  相似文献   
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A synthetic peptide corresponding to the second extracellular loop of the beta 1-adrenergic receptor was used as an antigen for antibody production in three rabbits. Antibodies of high titers were obtained in all rabbits. Only one rabbit yielded antibodies which decreased radioligand binding on the receptor in a similar way to that described for autoantibodies in patients with dilated cardiomyopathy. These antibodies recognized the receptor protein in immunoblots. Epitope mapping indicated that the N-terminal sequence of the loop used as antigen was the target of the major antigen fraction. Incubation of antibodies with C6 glioma cell membranes or inner membranes of E. coli, which express the human beta 1-adrenergic receptor, resulted in a decrease in number of radioligand binding sites. This decrease was dependent on the concentration of antibody and of Mg++ ions. It was not affected by the GTP analog GppNHp or the beta 1 subtype-specific antagonist metoprolol. The agonist, isoproterenol, also induced a decrease but the effects of antibody and agonist were not additive. These results suggest that the antibodies induce a Mg(++)-dependent, 'active', labile conformation of the receptor, independent from coupling to the GTP regulatory protein, but similar to that induced by the agonist isoproterenol. This interpretation was corroborated by the beta 1-adrenergic receptor agonist-like effect of the antibodies on cardiomyocytes in culture.  相似文献   
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Abstract Several statistical models that have been suggested in the periodontal literature for describing longitudinal attachment level changes, such as the gradual loss, single-burst, multiple-burst, and random walk models as well as other models introduced in this paper are compared by their power to predict future attachment loss. The data used in this analysis is from 1061 sites of 8 subjects, with moderate to severe periodontal disease, monitored monthly for about a year. This study found that none of the suggested models could significantly outperform the naive mean predictor, which predicts the future attachment level from the past mean. It was also found that no single model, such as the burst, gradual, or random walk, together with measurement error can fully explain the variation in the data. These results indicate that in the course of one year, the attachment level change may not follow the same model. Consequently, a model that fits well to past data cannot be accurately extended to the future.  相似文献   
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Using an in vitro system, the growth characteristics and enzyme histochemical properties of 3 odontogenic keratocysts and 3 dentigerous cysts were studied. It was found that the epithelial cells of the keratocysts hut not of the dentigerous cysts grew in vitro. Furthermore, the epithelial-like cells of the keratocysts showed the same activities of acid phosphatase and NADH-diaphorase in vitro as earlier described in vivo. These enzymatic activities were increased in epithelial-like cells close to proliferating fibroblast-like cells, indicating a close relationship between these two cell types. The results are discussed in the light of the known clinical behaviour of the keratocysts and certain conclusions are also drawn concerning the suggested neo plastic potential of the keratocysts.  相似文献   
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The accessibility by telephone of primary health care was studied in Reykjavik and its surrounding municipalities. Comparison was also made between community run health centres and private practices. About 60% of the total population of Iceland live within the study area. The study used medical secretaries as patient substitutes. During the prescribed telephone time, all "patients" were able to make telephone contact with their practice facilities, and 80% reached their doctor within 10 min. The waiting time for non-acute appointments was never more than three days. The study did not detect any difference in accessibility between community run health centres and privately owned GP practices.  相似文献   
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Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer.  相似文献   
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