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Digestive Diseases and Sciences - Abdominal pain is a cardinal sign of functional bowel disorders (FBD), in favor of irritable bowel syndrome (IBS). However, the determinants of abdominal pain...  相似文献   
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The muscle intracellular (IC) free glucose concentration and the rate of muscle glycogen synthesis were measured by using in vivo 13C and 31P NMR spectroscopy in normal volunteers under hyperinsulinemic (≈300 pM) clamp conditions at the following three plasma glucose levels: euglycemia (≈6 mM), mild (≈10 mM), and high (≈16 mM) hyperglycemia. In keeping with biopsy studies, muscle IC free glucose concentration at euglycemia (−0.03 ± 0.03 mmol/kg of muscle, mean ± SEM, n = 10) was not statistically different from zero. A small but statistically significant amount of IC free glucose was observed during mild and high hyperglycemia: 0.15 ± 0.08 (n = 5) and 0.43 ± 0.20 mmol/kg of muscle (n = 5), respectively. Muscle glycogen synthesis rate, in mmol per kg of muscle per min, was 111 ± 11 at euglycemia (n = 10), 263 ± 29 during mild hyperglycemia (n = 5), and 338 ± 42 during high hyperglycemia (n = 5), these three rates being significantly different from each other. As previous in vitro and in vivo studies, these rates suggest a Km (concentration at which unidirectional glucose transport reaches half-maximal rate) of the muscle glucose transport system in the 15–25 mM range under hyperinsulinemic conditions. The low concentrations of muscle IC free glucose observed under hyperinsulinemic conditions were interpreted, with this estimate and in the framework of metabolic control theory, as glucose transport being the predominant step controlling muscle glucose flux not only at euglycemia but also during hyperglycemia.  相似文献   
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Intravascular catheters are inserted into almost all critically ill patients. This review provides up-to-date insight into available knowledge on epidemiology and diagnosis of complications of central vein and arterial catheters in ICU. It discusses the optimal therapy of catheter-related infections and thrombosis. Prevention of complications is a multidisciplinary task that combines both improvement of the process of care and introduction of new technologies. We emphasize the main component of the prevention strategies that should be used in critical care and propose areas of future investigation in this field.  相似文献   
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Spontaneous megakaryocytic colonies (CFU-MK) formation without the addition of Meg-CSA in myeloproliferative disorders (MPD) has been reported by many laboratories. The mechanism by which this occurs is still unknown. In our previous work we have found that the spontaneous colonies persisted in serum-free agar culture although the colony cells were smaller and the colony numbers fewer than in plasma clot culture and that monoclonal antibodies against IL3, IL6 and GM-CSF had no inhibitory effect on spontaneous CFU-MK in both semi-solid cultures. Recently, proto-oncogene c-mpl and c-mpl ligand, thrombopoietin (TPO), have been shown to specifically participate in the regulation of normal human megakaryocytopoiesis. In order to test the hypothesis that c-mpl c-mpl ligand pathway is involved in the spontaneous growth of megakaryocyte progenitors, we investigated mRNA expressions of c-mpl and TPO in cells grown in serum-free liquid culture using RT-PCR. The c-mpl expression was detected in the cultured cells from all nine patients (six with ET, two with PV, one with PMF) who had spontaneous CFU-MK in clonal assays. However, none of the patients expressed TPO mRNA in these cells. Pre-incubation of nonadherent mononuclear cells with thioester-modified antisense oligodeoxynucleotide to c-mpl at a concentration of 6μ M significantly decreased the cloning efficiency of spontaneous megakaryocyte growth by 42.5% ( P <0.05) in plasma clot assay (seven with ET, one with PV) and 69.6% ( P <0.05) in serum-free agar culture (six with ET, one with PV). In control experiments the introduction of a scrambled oligomer to antisense oligodeoxynucleotide had no such effect on spontaneous colony formation. These results indicate that c-mpl exerts an important effect in the growth of spontaneous megakaryocytopoiesis in MPD.  相似文献   
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Multiple mechanisms exist by which tumour cells can escape CD95-mediated apoptosis. Previous studies by our laboratory have shown that primary B cells from non-Hodgkin's Lymphoma (B-NHL) were resistant to CD95-induced cell death. In the current study, we have analysed the mechanisms underlying CD95 resistance in primary human lymphoma B cells. We report that FADD (FAS-associated death domain protein) and caspase-8 were constitutively expressed in lymphoma B cells and that the CD95 pathway was blocked upstream to caspase-8 activation. However, caspase-8 was processed and functional after treatment with staurosporine (STS). We found that the expression levels of FLICE (FADD-like interleukin-1 beta-converting enzyme)-Inhibitory Protein (c-FLIP) and Bcl-2-related proteins were heterogeneous in B-NHL cells and were not related to CD95 resistance. Finally, we report the absence of a CD95-induced signalling complex [death-inducing signalling complex (DISC)] in lymphoma B cells, with no FADD and caspase-8 recruitment to CD95 receptor. In contrast, DISC formation was observed in CD95-resistant non-tumoural (NT) B cells. Therefore, we propose that the absence of DISC formation in primary lymphoma B cells may contribute to protect these cells from CD95-induced apoptosis.  相似文献   
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Human lithostathine was initially isolated from pancreatic stones in patients with alcoholic calcifying chronic pancreatitis. It is secreted into the pancreatic juice where it was believed to inhibit stone formation. The N-terminal undecapeptide was assumed to play an important role in the mechanism, by adsorption to the crystal surface. Later, the role of lithostathine in calcite formation and growth was questioned, together with the associated mechanism of action. In particular, although lithostathine adsorbs on calcite crystal, this property does not now seem to be specific. Moreover, the N-terminal undecapeptide is not likely to have, by itself, the function of the entire protein. The different aspects of this controversy are reviewed and discussed, particularly in the light of recent structural biology. Comparative biological data now available allow us to draw an interesting parallel between lithostathine and other related proteins. Finally, lithostathine might affect stone formation and may also have another function which could be investigated in the other proteins belonging to the same structural family.  相似文献   
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