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941.
Modification of endogenous eicosanoid synthesis by dietary n-3 fatty acid supplementation reduces febrile responses, but the mechanisms underlying these effects in vivo have not been determined. In the present study, local inflammation was induced by intramuscular injection ofturpentine in rats fed control or n-3 supplemented diets for 8-9 weeks. In animals fed the control diet, turpentine induced fever, hypermetabolism, marked local inflammation (oedema), increased plasma IL-6 concentrations and raised cerebrospinal fluid (CSF) concentrations of PGE2. N-3 fatty acid supplementation significantly inhibited the rise in CSF PGE2, fever and hypermetaboHsm induced by turpentine. Local inflammation and increased plasma IL-6 concentrations were not affected by n-3 supplementation. These findings suggest that modification of dietary fat intake inhibits fever via reduced release of prostaglandins, probably within the brain, but does not affect the local or afferent signals involved in fever generation. 相似文献
942.
Capsaicin, substance P, and ovalbumin, instilled into the bladders of naive and ovalbumin (OVA) sensitized guineapigs caused inflammation, as indicated by increased vascular permeability. Histological changes after exposure to these compounds progressed with time from intense vasodilatation to marginalization of granulocytes followed by interstitial migration of leukocytes. In vitro incubation of guinea-pig bladder tissue with substance P and ovalbumin stimulated release of prostaglandin D(2) and leukotrienes. In vitro incubation of bladder tissue with capsaicin, OVA, prostaglandin D(2), leukotriene C(4), histamine, or calcium ionophore A-23587 all stimulated substance P release. These data suggest that bladder inflammation initiated by a variety of stimuli could lead to a cyclic pattern of release of inflammatory mediators and neuropeptides, which could result in amplification and persistence of cystitis after the inciting cause has subsided. 相似文献
943.
In anaesthetized, paralysed, ventilated pigs the ability of inhaled nitric oxide (80 ppm in 0(2)) to reduce the haemodynamic and respiratory effects of endothelin-1 administration (200 pmol/kg, i.v.) was evaluated. The mechanical properties of the respiratory system were evaluated by the rapid airway occlusion technique. The overall respiratory resistance, the interrupter resistance and the additional resistance that reflects the viscoelastic properties of tissues and the inequality of the time constant within the system were also evaluated. The results show that inhaled nitric oxide can act as a selective pulmonary vasodilator and as a bronchodilator to counteract the vasoconstrictor and bronchoconstrictor activity of endothelin-1. In the pig, nitric oxide inhaled at 80 ppm for 6 mitt reduced the changes in respiratory-, interrupter- and additional resistance due to endothelin-1 administration without significantly changing the static and dynamic elastance of the respiratory system. 相似文献
944.
Cytokines play an important role in the development and persistence of the inflammatory lesions seen in Crohn's disease and ulcerative colitis. This review discusses the current thinking of the role of cytokines in chronic intestinal inflammation including the involvement of immunoregulatory cytokines within the Th1 and Th2 subsets. 相似文献
945.
The accumulation of unfolded proteins in the endoplasmic reticulum (ER) triggers the increased production of several ER-resident proteins. This signalling pathway exists in organisms as divergent as mammals and yeast, and is the only known example of an intracellular signalling system that links the ER and the nucleus. Recently, a transmembrane kinase similar in structure to growth-factor receptor kinases has been identified as a key component of the unfolded-protein-response pathway in yeast. 相似文献
946.
The Bcl-2 family of proteins: regulators of cell death and survival 总被引:15,自引:0,他引:15
The Bcl-2 protein inhibits apoptosis induced by a variety of signals, in a range of cell types and in diverse organisms, and it is implicated in both normal development and oncogenesis. Despite this central role, the mechanism of action of Bcl-2 is not yet clear. Recent studies have uncovered a number of Bcl-2-related gene products that regulate apoptosis either negatively or positively, and Bcl-2 forms heterodimers with at least one of these proteins, Bax. This article discusses the role of the Bcl-2 family of proteins in the light of these findings. 相似文献
947.
Protein phosphorylation is probably the major regulatory mechanism employed by eukaryotic cells. Much work has been devoted to the role of protein kinases and their modulation by hormones, growth factors and neurotransmitters. It is now appreciated that protein phosphatases are also key players in actively regulating many cellular processes. In this article we discuss recent advances in our understanding of the function of protein phosphatase 2A, one of the major serine/threonine-specific protein phosphatases. 相似文献
948.
949.
报道了测定CK-MM亚型的聚焦色谱法,此法简单,快速,结果可靠,线性范围宽,最低检测限(8U/L)较正常参考值低,比国外报道的类似方法高6倍以上,分离度亦有改进.测定了20例健康人血清亚型分布,与文献报道结果相近.该法自动化程度高,已在急性心梗的诊断中实际应用. 相似文献
950.
1993年8月,我们对本校园的银杏(o破办biAdxl)、杜仲(ffil‘xi1Tll7lm叨mm协的)、括楼op把h刀m尬h拐h对从w础)的叶片(4周左右,达到最大叶面积)、芽(05~Icm大小)、茎(当年生茎中部)及雌花(全花),按Simons和Grin-w沁h(*。njffe,1989,67:288)的方法加以修改进行了皮质醇含量的测定。即:取Zg新鲜的植物组织或器官,加10ml95%乙醇,匀浆后加等体积的二氯甲烷,提取48h,然后用0.lmol/L醋酸溶液洗3次,收集二氯甲烷相,抽干,残留物加lml无水乙醇溶解后,以2000Xg离心15min,取0.lml上清液于聚乙烯小管中(双管)… 相似文献