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41.
对wF(p,r,q)类算子的局部谱理论进行了比较系统的研究,得出如下结果:wF(p,r,q)类算子是次标量算子;wF(p,r,q)类算子是次可分解算子;wF(p,r,q)类算子的局部谱子空间与极大代数谱子空间相等;wF(p,r,q)类算子具有有限升等等.  相似文献   
42.
浅谈体育锻炼与合理营养   总被引:2,自引:0,他引:2  
范文全 《松辽学刊》2003,24(4):110-111,114
合理营养与体育锻炼是维持和促进健康的两个重要条件,以科学合理的营养为物质基础,以体育锻炼为手段,不同项目的锻炼,不同气候条件下的锻炼,不同年龄的锻炼,所需要的营养特点不同。因此,合理的营养对体育锻炼十分重要。  相似文献   
43.
在系统和循环系统概念的基础上对循环系统类cycle-system进行了讨论,解决了范畴问题,基本问题和同构不变性问题,分别得出了结果。  相似文献   
44.
45.
Bile acids and bile alcohols in the form of their conjugates are amphipathic end products of cholesterol metabolism with multiple physiological functions. The great variety of bile acids and bile alcohols that are present in vertebrates are tabulated. Bile salts have an enterohepatic circulation resulting from efficient vectorial transport of bile salts through the hepatocyte and the ileal enterocyte; such transport leads to the accumulation of a pool of bile salts that cycles between the liver and intestine. Bile salt anions promote lipid absorption, enhance tryptic cleavage of dietary proteins, and have antimicrobial effects. Bile salts are signaling molecules, activating nuclear receptors in the hepatocyte and ileal enterocyte, as well as an increasing number of G-protein coupled receptors. Bile acids are used therapeutically to correct deficiency states, to decrease the cholesterol saturation of bile, or to decrease the cytotoxicity of retained bile acids in cholestatic liver disease.  相似文献   
46.
Small HERC proteins are defined by the presence of one RCC1-like domain and a HECT domain. Having evolved out of one common ancestor, the four members of the family exhibit a high degree of homology in genomic organization and amino acid sequence, thus it seems possible that they might accomplish similar functions. Here we show that small HERC proteins interact with each other and localize to the same cellular structures, which we identify as late endosomes and lysosomes. We demonstrate interaction of HERC3 with the ubiquitin-like proteins hPLIC-1 and hPLIC-2 and we establish interaction of HERC5 with the metastasis suppressor Nm23B. While hPLIC proteins are not ubiquitinated by HERC3, HERC5 plays an important role in ubiquitination of Nm23B. In summary, although small HERC proteins are highly homologous showing the same subcellular distribution, they undergo different molecular interactions.  相似文献   
47.
The potential effects of synthetic unmethylated oligodeoxynucleotides (ODN) containing CpG motifs, mimicking bacterial DNA, has never been evaluated on the immune response in the teleost fish gilthead seabream (Sparus aurata), the most important fish species in Mediterranean aquaculture. First, binding and competition studies have demonstrated that binding is saturated and promiscuous, suggesting the participation of several receptors. Moreover, leucocyte cytotoxic (NCC) activity, production of ROIs (reactive oxygen intermediates), and expression of immune-relevant genes was greatly primed by ODNs. Focusing on the mechanism, the TLR9 gene is widely distributed in seabream tissues and differently regulated in vitro by several stimuli. Moreover, and for the first time in fish, TLR9 mRNA has been detected in lymphocytes as the main cell-source. To conclude, ODNs containing GACGTT, GTCGTT (optimal for mouse and human, respectively) or AACGTT motifs are the most potent inducers of seabream immunity, whilst the involvement of TLR9 is under debate.  相似文献   
48.
Extracellular domains of some cellular receptors expressed in the organisms at different levels of development belong to three-fingered protein (TFP) fold. The Homo sapiens genome encodes at least 45 genes containing from one to three TFP domains (TFPDs), namely diverse paralogues of the Ly6 gene, CD59 and the receptors of activins, bone morphogenetic proteins, Mullerian inhibiting substance and transforming growth factor-β. C4.4a and urokinase/plasminogen activatory receptor contain two and three TFPD repeats, respectively. These diverse proteins have a low overall sequence similarity with each other and their hydrophobicity levels vary to a considerable degree. It is suggested that sequence differentiation within the TFPD led to distinct groups of proteins whose attributes were optimized to fit both the physicochemical properties specific to their functional microenvironment and selective targeting of their highly diversified extracellular cofactors. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Received 7 August 2008; accepted 29 August 2008  相似文献   
49.
It has been proposed that neuroinflammation, among other factors, may trigger an aberrant neuronal cell cycle re-entry leading to neuronal death. Cell cycle disturbances are also detectable in peripheral cells from Alzheimer’s disease (AD) patients. We previously reported that the anti-inflammatory 15- deoxy-Δ12,14-prostaglandin J 2 (15d-PGJ 2) increased the cellular content of the cyclin-dependent kinase inhibitor p27, in lymphoblasts from AD patients. This work aimed at elucidating the mechanisms of 15d-PGJ 2-induced p27 accumulation. Phosphorylation, half-life, and the nucleo-cytoplasmic traffic of p27 protein were altered by 15d-PGJ2 by mechanisms dependent on PI3K/Akt activity. 15d-PGJ 2 prevents the calmodulin-dependent Akt overactivation in AD lymphoblasts by blocking its binding to the 85-kDa regulatory subunit of PI3K. These effects of 15d-PGJ 2 were not mimicked by 9,10-dihydro-15-deoxy-Δ12,14- prostaglandin J 2, suggesting that 15d-PGJ 2 acts independently of peroxisome proliferator-activated receptor γ activation and that the α,β-unsaturated carbonyl group in the cyclopentenone ring of 15d-PGJ 2 is a requisite for the observed effects. Received 14 July 2008; received after revision 2 September 2008; accepted 12 September 2008  相似文献   
50.
Cardiolipin, the heart of mitochondrial metabolism   总被引:5,自引:0,他引:5  
Cardiolipin is a unique phospholipid, which is almost exclusively localized in the mitochondrial inner membrane where it is synthesized from phosphatidylglycerol and cytidinediphosphate-diacylglycerol. After primary synthesis, the mature acyl chain composition of cardiolipin is achieved by at least two remodeling mechanisms. In the mitochondrial membrane cardiolipin plays an important role in energy metabolism, mainly by providing stability for the individual enzymes and enzyme complexes involved in energy production. Moreover, cardiolipin is involved in different stages of the mitochondrial apoptotic process and in mitochondrial membrane dynamics. Cardiolipin alterations have been described in various pathological conditions. Patients suffering from Barth syndrome have an altered cardiolipin homeostasis caused by a primary deficiency in cardiolipin remodeling. Alterations in cardiolipin content or composition have also been reported in more frequent diseases such as diabetes and heart failure. In this review we provide an overview of cardiolipin metabolism, function and its role in different pathological states. Received 16 January 2008; received after revision 26 February 2008; accepted 26 March 2008  相似文献   
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