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The largest reported outbreak of type C botulism in fur production animals is described. Epidemiological investigation of 117 out of 157 (response rate, 74.5%) farms revealed that 44,130 animals died or were euthanized, while 8,033 animals with milder symptoms recovered. The overall death rate in all animals at risk was 21.7%. The death rates were significantly higher in blue and shadow foxes (24.2 and 27.8%, respectively) than in silver and blue silver foxes and minks (below 4%). All minks had been immunized against botulinum toxin type C. Deaths were associated with feed manufactured by a local processor, 83 of whose customer farms (70.9%) reported dead or sick animals. Five feedlots out of 19 delivered to the farms on the day preceding the onset of the outbreak (day 2) were associated with a death rate higher than 40%. These feedlots consisted of fresh feed processed on day 2 and feed processed 1 day earlier (day 1). In laboratory analysis, the day 2 feed contained botulinum toxin type C (>600 minimum lethal doses/g), while the day 1 feed did not contain toxin. Toxin was not detected in feed raw-material samples. Clostridium botulinum type C was detected by PCR in some feed components and in feed. However, as the feed temperature was continuously 8 degrees C or below and the pH was continuously 5.6 or below according to the manufacturer, it seems unlikely that spore germination and toxin formation occurred during overnight storage. Hence, the events leading to toxin formation were not determined.  相似文献   
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Development of composite inflorescences in the plant family Asteraceae has features that cannot be studied in the traditional model plants for flower development. In Gerbera hybrida, inflorescences are composed of morphologically different types of flowers tightly packed into a flower head (capitulum). Individual floral organs such as pappus bristles (sepals) are developmentally specialized, stamens are aborted in marginal flowers, petals and anthers are fused structures, and ovaries are located inferior to other floral organs. These specific features have made gerbera a rewarding target of comparative studies. Here we report the analysis of a gerbera EST database containing 16,994 cDNA sequences. Comparison of the sequences with all plant peptide sequences revealed 1656 unique sequences for gerbera not identified elsewhere within the plant kingdom. Based on the EST database, we constructed a cDNA microarray containing 9000 probes and have utilized it in identification of flower-specific genes and abundantly expressed marker genes for flower scape, pappus, stamen, and petal development. Our analysis revealed several regulatory genes with putative functions in flower-organ development. We were also able to associate a number of abundantly and specifically expressed genes with flower-organ differentiation. Gerbera is an outcrossing species, for which genetic approaches to gene discovery are not readily amenable. However, reverse genetics with the help of gene transfer has been very informative. We demonstrate here the usability of the gerbera microarray as a reliable new tool for identifying novel genes related to specific biological questions and for large-scale gene expression analysis.  相似文献   
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Clostridium botulinum type B was detected by multiplex PCR in the intestinal contents of a suddenly deceased 11-week-old infant and in vacuum cleaner dust from the patient's household. C. botulinum was also isolated from the deceased infant's intestinal contents and from the household dust. The genetic similarity of the two isolates was demonstrated by pulsed-field gel electrophoresis and randomly amplified polymorphic DNA analysis, thereby confirming that dust may act as a vehicle for infant botulism that results in sudden death.  相似文献   
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Prevention Science - The long-term sustainment of bullying prevention programs has rarely been investigated. This study addresses this gap by identifying facilitators and barriers to the systematic...  相似文献   
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ObjectivesAsthma is one of the most common major noncommunicable diseases in the world and affects individuals of all ages. Medication is used to achieve and maintain quality of life (QOL) for people with asthma. Telehealth interventions offer optimized and personalized symptom monitoring with timely treatment adjustment and the potential to increase medication adherence for individuals with asthma. This study examines and synthesizes the available data on the change in the QOL for patients with asthma who use interactive telehealth interventions, and identifies the most effective telehealth modalities used for intervention in this area.MethodsLiterature searches were conducted in 5 databases in November 2018 for studies measuring a change in QOL for patients with asthma. Study QOL outcomes, where possible, were pooled in a meta-analysis.ResultsSeventeen publications (describing 16 studies) comprising 2015 patients were included. Based on a meta-analysis, interactive telehealth interventions can improve QOL outcomes for people living with asthma, although the improved effects may be small: web portals (0.51, 95% confidence interval [CI] –0.00 to 1.03), interactive smartphone apps (0.30, 95% CI –0.16 to 0.76) and remote monitoring (standardized mean difference 0.20, 95% CI –0.11 to 0.52). Intervention delivery modalities identified include interactive web portals, smartphone apps, and remote monitoring programs.ConclusionsThe findings provide a comprehensive overview of the available literature on interactive telehealth interventions, including interactive web portals, smartphone apps, and remote monitoring programs. These findings demonstrated that a positive change in QOL can be attributed to these interventions and provide evidence for the implementation of telehealth interventions for individuals with asthma.  相似文献   
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Recognition of dated and contemporary famous faces, short-term memory, and visuospatial abilities were investigated in adults aged 75 years and older as a function of apolipoprotein E (APOE) genotype, epsilon4 or not epsilon4, and whether participants recorded normal or low levels of B vitamins. No associations between B vitamins and APOE were identified in respect to short-term memory or visuospatial skills, or for contemporary famous faces. However, in respect to the recognition of dated famous faces, deficits in persons carrying the epsilon4 allele who also recorded low vitamin B(12) values were found. The results suggest that the neurological structures and processes supporting face recognition may be vulnerable to the combined influence of the APOE epsilon4 allele and low levels of vitamin B(12). This finding was unrelated to incipient dementia up to 6 years following testing. The results are discussed with reference to the neuroanatomical reserves that epsilon4 carriers may possess.  相似文献   
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Musicians show enhanced auditory processing compared to nonmusicians. However, the neural basis underlying the effects of musical training on rapid plasticity in auditory processing has not been systematically studied. Here, the rapid (one session) learning-related plastic changes in event-related potential (ERP) responses for pitch and duration deviants between passive blocks were compared between musicians and nonmusicians. Passive blocks were interleaved with an active discrimination task. In addition to musicians having faster and stronger overall source activation for deviating sounds, source analysis revealed rapid plastic changes in the left and right temporal and left frontal sources that were present only in musicians. Source activation decreased in these areas even without focused attention. Furthermore, deviant-related ERP responses above the parietal areas decreased after the active task in both musicians and nonmusicians. Taken together, the results indicate enhanced rapid plasticity in sound change discrimination and perceptual learning in musicians when compared with nonmusicians.  相似文献   
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