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991.
Sensitivities of Germinating Spores and Carvacrol-Adapted Vegetative Cells and Spores of Bacillus cereus to Nisin and Pulsed-Electric-Field Treatment 总被引:1,自引:0,他引:1 下载免费PDF全文
Irene E. Pol Willy G. C. van Arendonk Hennie C. Mastwijk Judit Krommer Eddy J. Smid Roy Moezelaar 《Applied microbiology》2001,67(4):1693-1699
Treatment of Bacillus cereus spores with nisin and/or pulsed-electric-field (PEF) treatment did not lead to direct inactivation of the spores or increased heat sensitivity as a result of sublethal damage. In contrast, germinating spores were found to be sensitive to PEF treatment. Nisin treatment was more efficient than PEF treatment for inactivating germinating spores. PEF resistance was lost after 50 min of germination, and not all germinated spores could be inactivated. Nisin, however, was able to inactivate the germinating spores to the same extent as heat treatment. Resistance to nisin was lost immediately when the germination process started. A decrease in the membrane fluidity of vegetative cells caused by incubation in the presence of carvacrol resulted in a dramatic increase in the sensitivity to nisin. On the other hand, inactivation by PEF treatment or by a combination of nisin and PEF treatments did not change after adaptation to carvacrol. Spores grown in the presence of carvacrol were not susceptible to nisin and/or PEF treatment in any way. 相似文献
992.
Analysis of gene expression in rose petals using expressed sequence tags 总被引:13,自引:0,他引:13
Channelière S Rivière S Scalliet G Szecsi J Jullien F Dolle C Vergne P Dumas C Bendahmane M Hugueney P Cock JM 《FEBS letters》2002,515(1-3):35-38
993.
Guro Vasdal Judit Vas Ruth C. Newberry Randi Oppermann Moe 《Journal of applied animal welfare science : JAAWS》2019,22(2):197-205
The aim of this pilot study was to investigate the effects of commercially applied environmental enrichments on behavior and lameness in broilers. Two consecutive flocks of broilers were observed at 16 days and 30 days of age to investigate differences between enriched (peat, bales of lucerne hay, and elevated platforms) and control birds with regards to behavioral activities and lameness. More running (p < .001), worm running (p = .006), play fighting (p = .015), dust bathing (p = .009), and ground pecking while standing (p < .001) were observed at 16 days than at 30 days. Across both ages, enriched birds showed more wing flapping (p = .016), wing stretching (p = .002), body shaking (p = .002), ground scratching (p < .001), and ground pecking while standing (p < .001) and lying (p = .003) compared with control birds. Even when no enrichments were close, enriched birds showed more body shaking (p = .008) and ground pecking while standing (p < 0.001) and lying (p = .010) than birds in comparable locations in control pens. There was a tendency for a lower gait score (i.e., reduced lameness) with the enriched treatment (p = .077). In conclusion, enriched birds showed higher levels of several activities compared with control birds, and demonstrated higher levels in areas where no enrichments were present. 相似文献
994.
995.
Two yeast strains, producing needle-shaped ascospores under suitable conditions, were isolated from grapes grown in Hungary. Based on these two strains, Metschnikowia viticola (type strain NCAIM Y.01705, CBS 9950, JCM 12561) is proposed as a new yeast species. Considering its phenotypic features, the restriction fragment patterns of 18S rDNA and the sequence of the D1/D2 domain of 26S rDNA, the proposed new species is closely related to Candida kofuensis. 相似文献
996.
Valenciano M Kissling E Cohen JM Oroszi B Barret AS Rizzo C Nunes B Pitigoi D Larrauri Cámara A Mosnier A Horvath JK O'Donnell J Bella A Guiomar R Lupulescu E Savulescu C Ciancio BC Kramarz P Moren A 《PLoS medicine》2011,8(1):e1000388
Background
A multicentre case-control study based on sentinel practitioner surveillance networks from seven European countries was undertaken to estimate the effectiveness of 2009–2010 pandemic and seasonal influenza vaccines against medically attended influenza-like illness (ILI) laboratory-confirmed as pandemic influenza A (H1N1) (pH1N1).Methods and Findings
Sentinel practitioners swabbed ILI patients using systematic sampling. We included in the study patients meeting the European ILI case definition with onset of symptoms >14 days after the start of national pandemic vaccination campaigns. We compared pH1N1 cases to influenza laboratory-negative controls. A valid vaccination corresponded to >14 days between receiving a dose of vaccine and symptom onset. We estimated pooled vaccine effectiveness (VE) as 1 minus the odds ratio with the study site as a fixed effect. Using logistic regression, we adjusted VE for potential confounding factors (age group, sex, month of onset, chronic diseases and related hospitalizations, smoking history, seasonal influenza vaccinations, practitioner visits in previous year). We conducted a complete case analysis excluding individuals with missing values and a multiple multivariate imputation to estimate missing values. The multivariate imputation (n = 2902) adjusted pandemic VE (PIVE) estimates were 71.9% (95% confidence interval [CI] 45.6–85.5) overall; 78.4% (95% CI 54.4–89.8) in patients <65 years; and 72.9% (95% CI 39.8–87.8) in individuals without chronic disease. The complete case (n = 1,502) adjusted PIVE were 66.0% (95% CI 23.9–84.8), 71.3% (95% CI 29.1–88.4), and 70.2% (95% CI 19.4–89.0), respectively. The adjusted PIVE was 66.0% (95% CI −69.9 to 93.2) if vaccinated 8–14 days before ILI onset. The adjusted 2009–2010 seasonal influenza VE was 9.9% (95% CI −65.2 to 50.9).Conclusions
Our results suggest good protection of the pandemic monovalent vaccine against medically attended pH1N1 and no effect of the 2009–2010 seasonal influenza vaccine. However, the late availability of the pandemic vaccine and subsequent limited coverage with this vaccine hampered our ability to study vaccine benefits during the outbreak period. Future studies should include estimation of the effectiveness of the new trivalent vaccine in the upcoming 2010–2011 season, when vaccination will occur before the influenza season starts. Please see later in the article for the Editors'' Summary 相似文献997.
Association of polymorphisms in the dopamine D4 receptor gene and the activity-impulsivity endophenotype in dogs 总被引:1,自引:0,他引:1
Hejjas K Vas J Topal J Szantai E Ronai Z Szekely A Kubinyi E Horvath Z Sasvari-Szekely M Miklosi A 《Animal genetics》2007,38(6):629-633
A variable number of tandem repeats (VNTR) polymorphism in exon 3 of the human dopamine D4 receptor gene ( DRD4 ) has been associated with attention deficit hyperactivity disorder (ADHD). Rodents possess no analogous repeat sequence, whereas a similar tandem repeat polymorphism of the DRD4 gene was identified in dogs, horses and chimpanzees. Here, we present a genetic association study of the DRD4 VNTR and the activity-impulsivity dimension of the recently validated dog-ADHD Rating Scale. To avoid false positives arising from population stratification, a single breed of dogs (German shepherd) was studied. Two DRD4 alleles (referred to as 2 and 3a ) were detected in this breed, and genotype frequencies were in Hardy–Weinberg equilibrium. For modelling distinct environmental conditions, 'pet' and 'police' German shepherds were characterized. Police German shepherds possessing at least one 3a allele showed significantly higher scores in the activity-impulsivity dimension of the dog-ADHD Rating Scale than dogs without this allele ( P = 0.0180). This difference was not significant in pet German shepherds. To the best of our knowledge, this is the first report of an association between a candidate gene and a behaviour trait in dogs, and it reinforces the functional role of DRD4 exon 3 polymorphism. 相似文献
998.
999.
Three yeast strains, which are phenotypically indistinguishable from Debaryomyces hansenii, were recovered from secondary mineral deposits (stalactites and stromatolites) obtained in the Crystal Eyes Cave, Roraima Tepui Mountain, Venezuela. Analyses of the D1/D2 domains of the LSU rRNA gene as well as the concatenated sequences of the nearly entire SSU rRNA gene, the ITS regions and the D1/D2 domains of the LSU rRNA gene confirmed the placement of these strains in the genus Debaryomyces, but relationship with all valid species of D. hansenii complex was distant. Based on the observed considerable sequence divergence the three strains are proposed as a new species, D. psychrosporus sp. nov., with the type strain NCAIM Y.01972(T) (CBS 11845(T), NRRL Y-48723(T)). 相似文献
1000.