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991.
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The authors describe their indication tactics for AAA elective treatment. Based on one-month morbidity and mortality they evaluate the results obtained in the past six years and compare the methods of open surgery, endovascular repair and combined strategy in AAAs elective repair.  相似文献   
994.
The authors describe the method of surgical aortic banding for better stent-graft fixation in cases of problematic aortic neck in the endovascular infrarenal aneurysms repair.  相似文献   
995.
Oxidative stress and especially its connection with many diseases has been discussed much recently. Among markers of oxidative stress there appear new and quite specific ones called advanced oxidation protein products (AOPPs). We tried to influence the level of AOPPs by an antioxidant therapy with N-acetylcysteine. Fourteen individuals with many cardiovascular risk factors were examined. All these patients were administered acetylcysteine (NAC) 600 mg/day orally during 20 days. Before starting the therapy we determined AOPP, albumin cobalt binding (ACB), glucose, creatinine, urea, ALT, AST, cholesterol, LDL, HDL and triglycerides values in peripheral venous blood in all individuals. After finishing our intervention we determined AOPP, ACB and glucose level again. Our results show a statistically significant decrease in AOPP levels after 20-day N-acetylcysteine therapy (medians, initially 82.2, at study end 74.3 umol/l, p = 0.039). We demonstrate a significant decrease in AOPP levels after 20-day N-acetylcysteine therapy in dose 600 mg/day.  相似文献   
996.
Lipid rafts are established as critical structures for a variety of cellular processes, including immune cell activation. Beyond their importance for initial immune cell activation at the immunological synapse, lipid rafts are now also being recognized as important sites for cytokine and growth factor signal transduction, both in immune cells as part of secondary regulatory processes, and in non-immune cells. This review summarizes current knowledge regarding the roles of rafts in cytokine signaling and emphasizes the need for measures to better standardize the study of rafts.  相似文献   
997.
To disperse their spores to new sites, filamentous fungi and bacteria need to erect aerial filaments, which develop into fruiting bodies and spore-bearing structures. The first challenge to aerial development is breaking surface tension at an aqueous-air interface, and in both groups of microorganisms, surface-active proteins take part in the initiation of aerial morphogenesis. Comparative analysis of fungi and bacteria is providing new insights into the means by which aerial filamentation is accomplished.  相似文献   
998.
Rafts: scale-dependent, active lipid organization at the cell surface   总被引:9,自引:1,他引:8  
Rafts have been conceptualized as lateral heterogeneities in the organization of cholesterol and sphingolipids, endowed with sorting and signaling functions. In this review we critically examine evidence for the main tenet of the 'raft hypothesis', namely lipid-dependent segregation of specific membrane components in the plasma membrane. We suggest that conventional approaches to studying raft organization wherein membranes are treated as passive, thermally equilibrated systems are unlikely to provide an adequate framework to understand the mechanisms of raft-organization in vivo. An emerging view of raft organization is that it is spatio-temporally regulated at different scales by the cell. This argues that rafts must be defined by simultaneous observation of components involved in particular functions. Recent evidence from the study of glycosylphosphatidyl inositol-anchored proteins, a common raft-marker, supports this picture in which larger scale, more stable rafts are induced from preexisting small-scale lipid-dependent structures actively maintained by cellular processes.  相似文献   
999.
Ischemic preconditioning increases the heart's tolerance to a subsequent longer ischemic period. The purpose of this study was to investigate the role of gap junction communication in simulated preconditioning in cultured neonatal rat cardiac myofibroblasts. Gap junctional intercellular communication was assessed by Lucifer yellow dye transfer. Preconditioning preserved intercellular coupling after prolonged ischemia. An initial reduction in coupling in response to the preconditioning stimulus was also observed. This may protect neighboring cells from damaging substances produced during subsequent regional ischemia in vivo, and may preserve gap junctional communication required for enhanced functional recovery during subsequent reperfusion.  相似文献   
1000.
In this study we report the cloning and characterisation of the mouse Glut12 gene and examine for the first time its expression pattern in the earliest stages of development. Mouse Glut12 (mGlut12) was cloned from preimplantation embryos by 5'RACE RT-PCR using primers designed from an EST clone corresponding to a human GLUT12 antigenic sequence after positive immunoreactivity was observed in mouse two-cell embryos by western immunoblotting. The mGlut12 gene contains an open reading frame of 1869 base pairs, potentially encoding a polypeptide of 622 amino acids. The predicted mGLUT12 protein bears all the hallmarks of the SLC2A family of hexose transporters and shares an 83% sequence homology to human GLUT12. Consistent with its human homolog mGlut12 mRNA is found highly expressed in skeletal and cardiac muscle and fat. Additionally, it was also found in the uterus and during early embryogenesis. During early development in the mouse, Glut12 expression is clearly apparent in ovulated oocytes and two-cell embryos but declines in day 3 morulae. With the exception of some Glut12 expression apparent in blastocysts, Glut12 mRNA remains at low to undetectable levels until E11.  相似文献   
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