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881.
A plasmid containing the human preprourokinase gene cDNA under the control of the simian virus 40 early region promoter was introduced into CHO-K1 cells and recombinant cell lines secreting a relatively high level of urokinase were obtained. In the course of studying the effects of various agents on the recombinant cell lines, we found that exposure of recombinant cells to 5 mM butyrate for 24 hours resulted in a 2-3 fold increase in urokinase production. The induction by butyrate was dose-dependent. The half maximal dose was approximately 2 mM; maximal stimulation occurred at 5-10 mM. Cell growth, on the other hand, was inhibited by butyrate concentrations greater than 2.5 mM. The response of cells to butyrate was rapid: a significant increase in urokinase production was observed 6 hours after exposure to 5 mM butyrate. Butyrate treatment increased not only the extracellular level but also the intracellular level of urokinase.  相似文献   
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ObjectiveThe recent introduction of the term metabolic associated fatty liver disease (MAFLD) sought to reclassify nonalcoholic fatty liver disease (NAFLD). MAFLD is thought to improve the encapsulation of metabolic dysregulation. However, recent evidence has found significant differences between MAFLD and NAFLD, and prevailing knowledge has largely arisen from studies on NAFLD. Hence, we conducted a meta-analysis and systematic review of the outcomes associated with MAFLD.MethodsMEDLINE and Embase databases were searched for articles relating to outcomes in MAFLD. Analysis was conducted in random effects with hazard ratios (HRs) to account for longitudinal risk assessment of mortality and systemic complications.ResultsA total of 554 articles were identified, of which 17 articles were included. MAFLD resulted in an increase in the overall mortality (HR, 1.24; confidence interval [CI], 1.13-1.34), cancer-related mortality (HR, 1.27; CI, 1.01-1.54), and cardiovascular disease mortality (HR, 1.28, 1.03-1.53; P = .04) compared with non-MAFLD. MAFLD also increases the risk of cardiovascular events (HR, 1.49; CI, 1.34-1.64; P < .01), stroke (HR, 1.55; CI, 1.37-1.73; P < .01), and chronic kidney disease (HR, 1.53; CI, 1.38-1.68). The presence of MAFLD was also associated with an increased risk of heart failure, obstructive sleep apnea, and malignancy.ConclusionMAFLD can significantly elevate the risk of systemic diseases and mortality. The care of MAFLD thus requires interdisciplinary collaboration, and future clinical trials conducted on MAFLD should aim to reduce the incidence of end-organ damage aside from improving liver histology.  相似文献   
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Magnocellular neurosecretory cells were antidromically identifiedin the hypothalamic paraventricular nucleus of urethane-anesthetized,ovariectomized female rats following electrical stimulationof the neurohypophysis The vasopressinergic cells with a phasicpattern of spontaneous discharge and the oxytocinergic cellswith a tonic pattern of discharge were distinguished and usedto examine the response associated with water or NaCl (154 mM)application to the pharyngolaryngeal regions. The water applicationproduced a reduction in the discharge of vasopressinergic cellsin the non-dehydrated condition, while there was no appreciablechange in the discharge of oxytocinergic cells after water application.The discharges in the vasopressinergic and oxytocinergic neuronswere unchanged after NaCl application. Because neural dischargein the vasopressinergic cell has been shown to be linked tovasopressin secretion, these findings suggest that pharyngolaryngealwater signals may actively modulate the fluid balance throughvasopressin.  相似文献   
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Studies made on cultured skin fibroblasts obtained from a patient with primary cortisol resistance are described. Whole cell in vitro assays, using the patient's fibroblasts revealed a reduction in the dexamethasone binding capacity (7.86 +/- 0.73 fmol/micrograms DNA, mean +/- SD, n = 3; normal: 15.2 +/- 1.90 fmol/micrograms DNA, n = 8) and an apparently normal dissociation constant (3.69 +/- 0.15 nM; normal: 3.74 +/- 0.40 nM). In addition, the effects of glucocorticoids on DNA synthesis in these cells were examined. DNA synthesis was inhibited by dexamethasone both in normal fibroblasts and in the patient's cells, but the patient's cells were less sensitive to this inhibition, indicating resistance of the cells to glucocorticoid in vitro. These results suggest that the resistance of target tissues to glucocorticoids is due to the reduction in receptor number and that this is the primary defect in this new type of primary cortisol resistance in man.  相似文献   
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Polymerization of diphenyl-2-pyridylmethyl methacrylate was carried out with the complexes of organolithium compounds with 22 chiral ligands. Helix-sense-selectivity of the polymerization was largely affected by a slight structural difference of chiral ligands. (+)-(S)-2-(1-Pyrrolidinylmethyl)pyrrolidine was the most effective ligand in producing a one-handed helical polymer with narrow molecular weight distribution.  相似文献   
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