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1.
Arata Hidano Takehisa Yamamoto Yoko Hayama Norihiko Muroga Sota Kobayashi Takeshi Nishida Toshiyuki Tsutsui 《PloS one》2015,10(3)
Multidrug-resistant enterococci are considered crucial drivers for the dissemination of antimicrobial resistance determinants within and beyond a genus. These organisms may pass numerous resistance determinants to other harmful pathogens, whose multiple resistances would cause adverse consequences. Therefore, an understanding of the coexistence epidemiology of resistance genes is critical, but such information remains limited. In this study, our first objective was to determine the prevalence of principal resistance phenotypes and genes among Enterococcus faecalis isolated from retail chicken domestic products collected throughout Japan. Subsequent analysis of these data by using an additive Bayesian network (ABN) model revealed the co-appearance patterns of resistance genes and identified the associations between resistance genes and phenotypes. The common phenotypes observed among E. faecalis isolated from the domestic products were the resistances to oxytetracycline (58.4%), dihydrostreptomycin (50.4%), and erythromycin (37.2%), and the gene tet(L) was detected in 46.0% of the isolates. The ABN model identified statistically significant associations between tet(L) and erm(B), tet(L) and ant(6)-Ia, ant(6)-Ia and aph(3’)-IIIa, and aph(3’)-IIIa and erm(B), which indicated that a multiple-resistance profile of tetracycline, erythromycin, streptomycin, and kanamycin is systematic rather than random. Conversely, the presence of tet(O) was only negatively associated with that of erm(B) and tet(M), which suggested that in the presence of tet(O), the aforementioned multiple resistance is unlikely to be observed. Such heterogeneity in linkages among genes that confer the same phenotypic resistance highlights the importance of incorporating genetic information when investigating the risk factors for the spread of resistance. The epidemiological factors that underlie the persistence of systematic multiple-resistance patterns warrant further investigations with appropriate adjustments for ecological and bacteriological factors. 相似文献
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A Y Kwong P C Wong R C Ko 《Comparative biochemistry and physiology. B, Comparative biochemistry》1990,95(1):193-197
1. All major classes of lipids were found in the young adults in brain (22 days post-infection) and gravid Angiostrongylus cantonensis in lung of rats (34 days post-infection) comprising approximately 60% of phospholipids, 30% of neutral lipids and the rest, glycolipids. 2. The relative composition of phospholipids were quite similar between worms from the two different habitats, with phosphatidylcholine predominating. The glycolipid profiles were also similar. 3. More neutral lipids in the worms from brain existed as cholesterol and cholesterol esters than those from the lung. More than 20% of the fatty acids in these lipids of the brain were found as C10-C14 acids while oleic acid was the main component in the lung worm. 相似文献
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Female sex steroid induced epithelial changes in the gallbladder of the ovariectomized Syrian hamster. 总被引:1,自引:0,他引:1
Ovariectomized Syrian hamsters treated by female sex steroids during a 1-month period show gallbladder surface epithelial changes in the fundic area consistent with apical bulging and decapitations of the epithelial cells. These events were detected in the infundibulum and the fundic or body regions of estrogen- and estrogen+progesterone-treated hamsters. In control hamsters, these events were restricted to the region in the vicinity of the bile duct. Following steroid treatment, intraluminal deposits detected resembled Ca-bilirubinate deposits described in previous studies while decapitations are similar to endometrial epithelium changes associated with hormonal physiological changes or treatments. Moreover some small electron-dense deposits are comparable to those found in human cholesterol gallstones. This report indicates that, besides an alteration in bile composition, cell fragments originating from the surface epithelium of the bile duct and/or of the gallbladder mucosal epithelium could participate in gallstone nucleation. 相似文献
5.
T Torlińska M Grzymis?awski J Paluszak P Sosnowski L Torliński J Ko?lik 《Acta physiologica Polonica》1987,38(4):353-360
Short (7 days) T3-treatment has no influence on the plasma glucose and FFA concentration and blood lactate level, as well as on the hepatic glycogen content in the rats. The rise in T3 levels, observed in our study, was accompanied by a fall in T4 concentrations, indicating suppression of the endogenous T4 production. On the other hand, glycogenolytic activity of rat serum in vitro is the highest in the system: control liver slices-serum of rats pretreated with T3 as compared to the system: control liver slices-control serum. These observations may lead to conclusions, that serum of rats pretreated with T3 contains factors exhibiting the greater ability to mobilize glucose from liver slices than the control serum (euthyroid). The possibility, that pretreatment with T3 may cause a decrease in the number and/or affinity of beta-adrenergic receptors in the rat liver, is discussed. 相似文献
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Curt Koßwig 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1932,4(1):22-32
Ohne Zusammenfassung 相似文献
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Lacto-N-neotetraosylceramide incubated with human serum fucosyltransferase preparations gave rise to two fucoglycolipids. The faster migrating fucoglycolipid I on the basis of its thin-layer chromatographic mobility, susceptibility to alpha(1 leads to 2) fucosidase from Trichomonas foetus, radio-immunoprecipitation with Ulex europeus lectin and studies with Oh (Bombay) sera was identified as H-active glycolipid (H-I). The most probable structure of fucoglycolipid II should be that with fucose linked alpha(1 leads to 3) to N-acetylglucosamine. Lactosylceramide, ceramide trihexoside and globoside were not substrates for human serum fucosyltransferases. Lacto-N-neotetraosyl ceramide served as a fucose acceptor for all serum preparations tested while asialoganglioside was a substrate only when serum preparations containing H-gene dependent alpha-2-L-fucosyltransferase were used. With asialoganglioside only one radioactive reaction product was formed. 相似文献