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On the basis of specially developed scheme for the isolation of Listeria strains comprising 2 enrichment stages and the use of growth inhibitors, 128 L. monocytogenes cultures were isolated from clinical material, foodstuffs and sewage water. Highly virulent L.monocytogenes strains isolated from clinical material belonged to serovar 4b (54%) and 1/2a (38%), while those isolated from foodstuffs and sewage water belonged to 4b (74%). The restriction analysis of the chromosomal DNA of the isolated cultures with the use of restrictase EcoR1 on the basis of pulsed-field gel electrophoresis (PFGE) made it possible to distinguish Listeria strains in accordance with 5 types of restrictograms. The restrictograms of highly virulent L. monocytogenes strains, serovar 4b, belonged to types 1 and 2, while those of L. monocytogenes strains, serovar 1/2a, belonged to types 2 and 3. The comparative use of different methods for typing L. monocytogenes (sero-, phago-, bio- and resistotyping, the analysis of plasmid composition and restriction analysis) revealed that the combination of serotyping and restriction analysis on the basis of PFGE proved to be most promising for the characterization of the isolated L. monocytogenes strains and the assessment of their epidemic importance. 相似文献
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SM Vlajkovic PR Thorne GD Housley DJ Mu?oz IS Kendrick 《Canadian Metallurgical Quarterly》1998,9(7):1559-1565
There is strong evidence for a purinergic signalling system in the inner ear which regulates auditory sensitivity. This study describes the terminating mechanism for purinergic signalling in the cochlear endolymphatic compartment via ecto-nucleotidases. Exogenous ATP was introduced into the scala media (SM) of the isolated, perfused guinea-pig cochlea, and the effluent was assayed for the adenine nucleotide metabolites by reverse-phase HPLC. Tissue viability was confirmed by fluorescence imaging of cochlear tissues. Extracellular ATP degradation to adenosine was Ca2+/Mg2+ dependent, and was not affected by inhibitors of intracellular ATPases and non-specific alkaline phosphatase. High azide concentration (5 mM) and suramin produced an inhibitory effect on ATP hydrolysis, consistent with inhibition of E-type ATPase activity. The Vmax of ATP hydrolysis (2564 mumol min-1 SM-1) was indicative of high ecto-ATPase activity. Our results support the role of ecto-nucleotidases as a principal mechanism for termination of purinergic signalling within SM, a compartment of the cochlea showing considerable P2X receptor expression. 相似文献
54.
IS Scott M Sheaff A Coumbe RM Feakins DS Rampton 《Canadian Metallurgical Quarterly》1998,33(2):168-173
The epoxyalkanoyl derivatives were designed and synthesized as ACE inhibitors. Coupling of unsaturated carboxylic acids with amino acids and following epoxidation with dimethyldioxirane gave the epoxyalkanoyls with high yield. The inhibitory activity of synthesized compounds on angiotensin converting enzyme was IC50 values of 0.06-5.5 microM. 相似文献
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This study is based on interviews with 37 persons fulfilling the DSM-IV criteria for kleptomania recruited through newspaper advertisements, and on 50 shoplifters interviewed directly after apprehension. Our hypothesis was that there are no absolute borders between 'pure' kleptomania according to DSM-IV and other forms of shoplifting. When asked about the latest case of shoplifting, one fifth of the shoplifters reported not having stolen the item for personal use and had later discarded it. A quarter of the kleptomaniacs reported ambivalence when asked if they needed the item in question. The degree of reported impulsivity and a feeling of not being oneself at the time of the theft was the same in the two groups. The two groups also estimated their degree of impulsivity, planning, thrill, relief, vengeance, need, pleasure on a Visual Analogue Scale (VAS) as well as the degree of psychiatric imbalance on the latest theft occasion. These estimates showed that there were no differences between the groups concerning the degree of planning, psychological imbalance and the need for the stolen item in question. The kleptomaniacs rated a feeling of inner tension before the theft higher than the shoplifters. The same was true concerning a feeling of relief during the theft and impulsivity. However, the shoplifters also rated high on all these items. Altogether, these findings support our hypothesis that many shoplifters, even if they do not fulfill all DSM criteria for kleptomania, may constitute a significant medical problem and should be offered support and treatment. Anti-depressants as well as the educational programmes developed by the Shoplifters Alternatives may be effective not only in cases of kleptomania but also for more unselected groups of non-professional shoplifters. 相似文献
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R Bell DA Collier SQ Rice GW Roberts CH MacPhee RW Kerwin J Price IS Gloger 《Canadian Metallurgical Quarterly》1997,241(3):630-635
Systematic scans of the genome using microsatellite markers have identified chromosome 6p21.1 as a putative locus for schizophrenia in multiply affected families. There is also evidence from a series of studies for a role of abnormal phospholipid metabolism in schizophrenia. In light of these findings, and the role of platelet activating factor in neurotransmission and neurodevelopment, we have examined the LDL-PLA2 (plasma PAF acetylhydrolase, PAF-AH) gene, a serine dependent phospholipase that has been mapped by hybrid mapping to chromosome 6p21.1, as a positional candidate gene for schizophrenia. The gene was systematically screened using SSCP/HD analysis for polymorphisms associated with the disease. Four polymorphic variants were found within the gene and studied in a group of 200 schizophrenic patients and 100 controls. The variant in exon 7 (Iso195Thr) was found to be weakly associated with schizophrenia (p = 0.04) and the variant in exon 11 (Val379Ala) almost reached significance (p = 0.057). After correcting for multiple testing no significant associations were detected. Haplotype analysis combining pairs of polymorphisms also provided no evidence for association of this gene with schizophrenia in our sample of patients. 相似文献
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To determine how the patterns of inpatient hospital care for HIV-infected patients have evolved in recent years, we analyzed data obtained from a statewide hospital discharge database from Maryland for the years 1988, 1990, and 1992. For each of these years, we compared demography, diagnoses, lengths of stay, use of the intensive care unit, third-party payer, and hospital charges (inflation-adjusted to 1992 dollars). HIV-infected patients accounted for 0.42% of all Maryland's hospital admissions in 1988, 0.68% in 1990, and 1.1% in 1992, with progressively more women and African-Americans hospitalized. Average lengths of stay fell from 11.7 days (1988) to 10.7 days (1990) and 9.5 days (1992) (p < 0.0001). Average charges per admission fell from $11,634 (1988) to $9,938 (1990) and $8,618 (1992) (p < 0.0001). Medicare or Medicaid paid for 50.9% of hospital admissions in 1988, 56.8% in 1990, and 66.8% in 1992 (p < 0.001). In-hospital mortality rates (7.8% in 1988, 7.9% in 1990, and 7.7% in 1992; p = 0.783) were stable, as was severity of illness. P. carinii pneumonia (PCP) was the most common principal diagnosis, but it declined in prevalence from 13.6% in 1988 to 9.1% in 1992 (p < 0.0001). Principal diagnoses of other opportunistic infections remained stable (8.0% in 1988, 9.9% in 1990, 8.6% in 1992; p = 0.90), as did other nonopportunistic infections (32.8% in 1988, 27.2% in 1990, and 30.0% in 1992; p = 0.16). Non-PCP pneumonias increased from 7.6% (1988) to 10.2% (1992) (p < 0.0001). Substance abuse as a principal or secondary diagnosis increased from 30.9% (1988) to 34.3% (1992) (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献