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101.
The copy number and genetic location of IS200 have provided evidence of strain relatedness in many serotypes of Salmonella. In this study, 100 isolates of the related serotypes Livingstone (6,7:d:l,w) and Eimsbuettel (6,7,14:d:l,w), representing 10 ribotype/biotype (RT/BT) groups isolated from human and non-human sources in seven countries over a 26-year period, were examined for their IS200 profiles. The distribution of IS200 in strains of these serotypes was limited, being present in all 53 isolates of ribotype 1 (RT1) and its variant type RT6, in one of five isolates of RT5 but in none of 42 isolates of RTs 2, 3 or 4. Although the seven IS200 profiles identified in RT1 isolates were of little value for further discrimination within different biotype groups, they were extremely valuable for confirming serotype: isolates of RT1/BT8/IS200 profile A (or its variants) and those of RT1/BT3/IS200 profile B (or its variants) were almost invariably associated with serotypes Livingstone and Eimsbuettel, respectively. 相似文献
102.
To better understand mechanisms that limit rAAV transduction in the lung, we have evaluated several unique features of rAAV infection in polarized primary airway epithelial cultures. rAAV was found to transduce the basolateral surface of airway epithelia 200-fold more efficiently than the apical membrane. These differences in membrane infection correlated with the abundance of apical heparan sulfate proteoglycan (AAV-2 receptor) and virus binding. UV irradiation augmented rAAV transduction greater than 20-fold, only when virus was applied to the apical membrane. Ultrastructural analysis of UV-irradiated primary cultures demonstrated significant changes in microvilli architecture following exposure to 25 J/m2 UV. Although virus binding and the abundance of heparan sulfate proteoglycan were not increased at the apical membrane following UV irradiation, increased receptor-independent endocytosis of fluorescent beads was seen at the apical membrane following UV irradiation. We hypothesize that endocytotic processes associated with apical membrane-specific pathways of viral entry, and/or processing of virus to the nucleus, may be altered following UV irradiation. Interestingly, UV irradiation had an inhibitory effect on rAAV transduction from the basolateral membrane, which correlated with a decrease in the abundance of heparan sulfate proteoglycan at the basal membrane. In summary, these findings suggest that independent pathways of viral transduction may occur in the apical and basolateral compartments of polarized airway epithelia. 相似文献
103.
PB Mortier VL Martinot Y Anastassov JF Kulik A Duhamel PN Pellerin 《Canadian Metallurgical Quarterly》1997,34(3):247-255
We have analysed randomized controlled studies which reported the incidence of postoperative nausea and vomiting (PONV) after propofol anaesthesia compared with other anaesthetics (control). Cumulative data of early (0-6 h) and late (0-48 h) PONV were recorded as occurrence or non-occurrence of nausea or vomiting. Combined odds ratio and number-needed-to-treat were calculated for propofol as an induction or maintenance regimen, early or late outcomes, and different emetic events. This was performed for all control event rates and within a range of 20-60% control event rates. We analysed 84 studies involving 6069 patients. The effect of propofol on PONV was dependent mainly on the method of administration, time of measurement and range of control event rates. When all studies were included the number-needed-to-treat to prevent PONV with propofol was more than 9 when used for induction of anaesthesia and at best 6 when used for maintenance. Within the 20-60% control event rate range, best results were achieved with propofol maintenance to prevent early PONV: the number-needed-to-treat to prevent early nausea was 4.7 (95% confidence interval 3.8-6.3), vomiting 4.9 (4-6.1) and any emetic event 4.9 (3.7-7.1). Within the 20-60% control event rate, of five patients treated with propofol for maintenance of anaesthesia, one will not vomit or be nauseated in the immediate postoperative period who would otherwise have vomited or been nauseated. This may be clinically relevant. In all other situations the difference between propofol and control may have reached statistical significance but was of doubtful clinical relevance. Treatment efficacy should be established within a defined range of control event rates for meaningful estimates of efficacy and for comparisons. 相似文献
104.
105.
PB Martens 《Canadian Metallurgical Quarterly》1997,16(2):210-225
106.
KJ Rhodes BW Strassle MM Monaghan Z Bekele-Arcuri MF Matos JS Trimmer 《Canadian Metallurgical Quarterly》1997,17(21):8246-8258
The differential expression and association of cytoplasmic beta-subunits with pore-forming alpha-subunits may contribute significantly to the complexity and heterogeneity of voltage-gated K+ channels in excitable cells. Here we examined the association and colocalization of two mammalian beta-subunits, Kvbeta1 and Kvbeta2, with the K+ channel alpha-subunits Kv1.1, Kv1.2, Kv1.4, Kv1.6, and Kv2.1 in adult rat brain. Reciprocal coimmunoprecipitation experiments using subunit-specific antibodies indicated that Kvbeta1 and Kvbeta2 associate with all the Kv1 alpha-subunits examined, and with each other, but not with Kv2.1. A much larger portion of the total brain pool of Kv1-containing channel complexes was found associated with Kvbeta2 than with Kvbeta1. Single- and multiple-label immunohistochemical staining indicated that Kvbeta1 codistributes extensively with Kv1.1 and Kv1.4 in cortical interneurons, in the hippocampal perforant path and mossy fiber pathways, and in the globus pallidus and substantia nigra. Kvbeta2 codistributes extensively with Kv1.1 and Kv1.2 in all brain regions examined and was strikingly colocalized with these alpha-subunits in the juxtaparanodal region of nodes of Ranvier as well as in the axons and terminals of cerebellar basket cells. Taken together, these data provide a direct demonstration that Kvbeta1 and Kvbeta2 associate and colocalize with Kv1 alpha-subunits in native tissues and provide a biochemical and neuroanatomical basis for the differential contribution of Kv1 alpha- and beta-subunits to electrophysiologically diverse neuronal K+ currents. 相似文献
107.
108.
PB Jacobsen MR Widows DM Hann MA Andrykowski LE Kronish KK Fields 《Canadian Metallurgical Quarterly》1998,60(3):366-371
Hormonal treatments which have an androgenic effect have the potential to cause vocal changes. The changes in vocal fold structure and voice quality are considered to be irreversible. To date, studies have documented subjective vocal changes or documented single cases without detailed, baseline voice assessments. The impact on laryngeal function of women taking these androgenic treatments requires further detailed, objective assessment. The need for increased awareness of the actions of androgenic hormones on womens' voices, and the benefits of a thorough voice assessment are discussed. 相似文献
109.
110.
A field study undertaken in the city of S. Paulo is presented as part of the project Environment and Health in Developing Countries: An Analysis of Intra-Urban Differentials Using Existing Data financed by the Ministry of Foreign Affairs of the United Kingdom with academic support from the London School of Hygiene and Tropical Medicine (LSHTM). The research aim was to fill in the gaps in the information needed to establish associations between mortality, urbanization and the environment. Statistics were produced by means of existing data collected by city departments, research carried out by universities and census data. Data quality was assessed taking into consideration data coverage, accuracy, and sensibility to pinpoint deprived areas in the city of S. Paulo. Socioeconomic data were used to create a composite index for districts and subdistrict in order to form four socioeconomic zones. Mortality differentials between the zones by five broad age groups (0-4, 5-14, 15-44, 45-64 e 65+) and four ICD chapters (circulatory, respiratory, infectious and parasitic and external causes) are presented. The zoning used showed that 43.8% of S. Paulo residents live in areas under the worst socioeconomic conditions. Health data demonstrated that people living in this areas had higher rates of mortality then those living in the areas with the best conditions. Finally, excess mortality data are analyzed and suggested as a good method for allocating health resources. 相似文献