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Hepatic encephalopathy is a reversible state of altered cognition that may occur in patients with acute or chronic liver disease or porto-systemic shunt, and in which known neurological or psychiatric signs may develop. Nitrogenated substances from intestinal digestion reach the brain without being cleared by their passage through the liver due to the presence of porto-systemic shunt. We report two cases of patients with porto-systemic shunt diagnosed with recurrent chronic hepatic encephalopathy refractory to conventional medical treatment. They were satisfactorily treated with shunt embolization using interventionist radiology techniques.  相似文献   
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THYMUS SERPYLLOIDES ssp. GADORENSIS is endemic in the Betic region (Spain). Gas chromatography and GC/mass spectrometry studies of its essential oil showed its major components to be carvacrol and its biosynthetic precursors (gamma-terpinene and P-cymene).  相似文献   
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The prevalence of imipenem resistance among Pseudomonas aeruginosa isolates at a 195-bed tertiary care medical center in Cali, Colombia, rose from 2% in 1996 to 28% in 1997 and to over 40% in 2003. Many isolates showed high-level multiresistance, and phenotypic characterization suggested the spread of a predominant strain with minor variants. Sixty-six resistant isolates collected between February 1999 and July 2003 from hospitalized patients (n = 54) and environmental samples (n = 12) were subjected to a fuller analysis. Genetic fingerprints were compared by pulsed-field gel electrophoresis (PFGE) of SpeI-digested genomic DNA, and bla(IMP) and bla(VIM) genes were sought by PCR. PFGE and serotyping indicated that 52 of the 66 isolates belonged to a single strain, with 82% similarity; the PFGE pattern for this organism was designated pattern A. Two further pairs of isolates represented single strains; the remaining nine isolates were unique, and in the case of one isolate, no satisfactory PFGE profile could be obtained. The pattern A isolates were mostly of serotype O12 and were highly resistant to imipenem (MICs, 32 to >256 microg/ml), with this resistance decreased eightfold or more in the presence of EDTA. They yielded amplicons with bla(VIM)-specific primers, and sequencing of DNA from a representative isolate revealed bla(VIM-8), a novel allele with three polymorphisms compared with the sequence of bla(VIM-2). Two of these nucleotide changes were silent, but the third determined a Thr139Ala substitution. Only 4 of 13 resistant isolates (2 clinical isolates and 2 environmental isolates) assigned to other PFGE types carried bla(VIM) alleles, whereas the others were less multiresistant and mostly had lower levels of imipenem resistance (MICs, < or =32 microg/ml) which was not significantly reduced by EDTA. No bla(IMP) alleles were detected. During 2003, when the environmental study was undertaken, serotype O12 isolates with bla(VIM) were recovered from sinks and stethoscopes in the most-affected units, although not from the hands of staff; the problem declined once these reservoirs were disinfected and hygienic precautions were reinforced.  相似文献   
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The presence of nitric oxide synthase (NOS) in neuronal elements expressing the calcium-binding proteins calretinin (CR) and parvalbumin (PV) was studied in the rat main olfactory bulb. CR and PV were detected by using immunocytochemistry and the nitric oxide (NO) -synthesizing cells were identified by means of the reduced nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-diaphorase) direct histochemical method. The possible coexistence of NADPH-diaphorase and each calcium-binding protein marker was determined by sequential histochemical-immunohistochemical double-labeling of the same sections. Specific neuronal populations were positive for these three markers. A subpopulation of olfactory fibers and olfactory glomeruli were positive for either NADPH-diaphorase or CR. In the most superficial layers, groups of juxtaglomerular cells, superficial short-axon cells and Van Gehuchten cells demonstrated staining for all three markers. In the deep regions, abundant granule cells were NADPH-diaphorase- and CR-positive and a few were PV-immunoreactive. Scarce deep short-axon cells demonstrated either CR-, PV-, or NADPH-diaphorase staining. Among all these labeled elements, no neuron expressing CR or PV colocalized NADPH-diaphorase staining. The present data contribute to a more detailed classification of the chemically- and morphologically-defined neuronal types in the rodent olfactory bulb. The neurochemical differences support the existence of physiologically distinct groups within morphologically homogeneous populations. Each of these groups would be involved in different modulatory mechanisms of the olfactory information. In addition, the absence of CR and PV in neuronal groups displaying NADPH-diaphorase, which moreover are calmodulin-negative, indicate that the regulation of NOS activity in calmodulin-negative neurons of the rat olfactory bulb is not mediated by CR or PV.  相似文献   
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