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Rimstad  E.  Poppe  T.  Evensen  Ø.  Hyllseth  B. 《Acta veterinaria Scandinavica》1991,32(4):503-510
Atlantic salmon were selected from a fish farm with no previous record of pancreas disease (PD) or infectious pancreatic necrosis virus (IPNV) infection. Groups of fish were inoculated with either IPNV (strain Sp) from cell culture, organ material from fish with PD or control material as phosphate-buffered saline (PBS). Virological, histological and immunohistochemical examinations were carried out throughout the experiment. None of the fish died or showed clinical symptoms of PD. Histological examination revealed no pathological changes, and immunohistochemical studies were negative. Virus was isolated only sporadically from the group inoculated with organ material, whereas it was isolated consistently from the group inoculated with virus propagated in cell culture, as well as from in-contact control fish after the first week. In a latent carrier test, changes were entirely lacking in the first mentioned group, and were only slight in the last mentioned group. The data suggest that PD is not a transmissible disease, and that IPNV isolated from a PD outbreak does not play any part in the etiology of this disease.  相似文献   
3.
Environmental variables such as temperature and rainfall can directly affect the community structure of dipterans. Seasonal oscillations in the abundance of species of Drosophilidae reflect differences in how tolerant populations are to climatic conditions. Over a period of 14 months, we collected samples in two habitats in the Pampa biome in the municipality of São Luiz Gonzaga, state of Rio Grande do Sul, Brazil (28°24′28″S, 54°57′39″W). The influence of environmental variables on populations of Drosophilidae was evaluated for both collecting sites by using correlation analysis. The results suggested a negative correlation between the abundances of Drosophila cardinoides Dobzhansky & Pavan, Drosophila maculifrons Duda, Drosophila melanogaster Meigen, Drosophila nigricruria Patterson & Mainland, and Zygothrica vittimaculosa Burla with temperature, which is reflected in the distribution of these species within Brazil. Our findings are important for characterizing and preserving biodiversity in this almost-unknown biome in southern Brazil given the current climate change scenario.  相似文献   
4.

Background

End-of-life-care is often poor in individuals with dementia. Advanced care planning (ACP) has the potential to improve end-of-life care in dementia. Commonly ACP is completed in the last six months of life but in dementia there may be problems with this as decision-making capacity and ability to communicate necessarily decrease as the disease progresses. Choosing the right time to discuss ACP with people with dementia may be challenging given the duration of the illness may be up to nine years.

Aims

To explore the acceptability of discussing ACP with people with memory problems and mild dementia shortly after diagnosis.

Methods

In-depth interviews were conducted with 12 patients and eight carers who had participated in ACP discussions and six staff members from a memory clinic and a community mental health team who had either conducted or attended the discussions for training purposes.

Results

Patients and carers found ACP a positive intervention that helped them think about the future, enabled people with dementia to make their wishes known, and resulted in their feeling relieved and less worried about the future. The importance of sharing the ACP documentation between health service providers was highlighted.

Conclusions

This qualitative evaluation of ACP in early dementia has encouragingly positive results which support the wider application of the intervention in memory services and community mental health teams. Strategies are suggested to support the implementation of ACP further in clinical practice.  相似文献   
5.
To study negative interactions between phytochromes, phytochrome B (phyB) overexpressor lines, the mutants phyA-201, phyB-4, phyB-5, phyD-1, phyA-201 phyB-5, phyA-201 phyD-1, and phyB-5 phyD-1 of Arabidopsis were used. Endogenous phyB, but not phytochrome D (phyD), partly suppressed phytochrome A (phyA)-dependent inhibition of hypocotyl elongation in far-red light (FR). Dichromatic irradiation demonstrated that the negative effect of phyB was largely independent of the photoequilibrium, i.e. far-red light absorbing form of phytochrome formation. Moreover, phyB-4, a mutant impaired in signal transduction, did not show a loss of inhibition of phyA by phyB. Overexpression of phyB, conversely, resulted in an enhanced inhibition of phyA function, even in the absence of supplementary carbohydrates. However, overexpression of a mutated phyB, which cannot incorporate the chromophore, had no detectable effect on phyA action. In addition to seedling growth, accumulation of anthocyanins in FR, another manifestation of the high irradiance response, was strongly influenced by phyB holoprotein. Induction of seed germination by FR, a very low fluence response, was suppressed by both endogenous phyB and phyD. In conclusion, we show that both classical response modes of phyA, high irradiance response, and very low fluence response are subject to an inhibitory action of phyB-like phytochromes. Possible mechanisms of the negative interference are discussed.  相似文献   
6.
Fructification and yield of the edible mushrooms Pleurotus pulmonarius and Stropharia rugosoannulata are clearly enhanced when wheat straw is supplemented with 30% Lolium perenne grass chaff. The bioactive compound in the methanol extract of grass chaff was identified as beta-adenosine. In vitro biological activity tests showed that 0.012 mg of beta-adenosine per ml of medium stimulated earlier fructification of Pleurotus pulmonarius. Mushroom fruiting trials showed that when 12 mg beta-adenosine was added to 1 kg wet wheat straw, primordia of Pleurotus pulmonarius appeared two days earlier and primordia of Stropharia rugosoannulata appeared 18 days earlier when compared to pure wheat straw substrate. This concentration of beta-adenosine had no impact on the mushroom yield of Pleurotus, but resulted in a 2.2 fold increase in yield for Stropharia. beta-Adenosine at 25 mg per kg wet wheat straw increased the yield of Pleurotus with 52% and the yield of Stropharia with 258%, but this concentration delayed primordial formation in Pleurotus.  相似文献   
7.
A case of intracellular systemic infection with the diplomonad flagellate Spironucleus barkhanus in farmed Arctic char Salvelinus alpinus is described. The parasites were widely disseminated throughout the vasculature and in most organs. Aggregates of the parasites were seen within well-defined structures regarded as host cells in capillaries and sinusoids of the liver, spleen and head kidney. Intracellular infection with Spironucleus spp. has never previously been reported. The prevalence of infection and mortality in the affected farm was low. In contrast to systemic spironucleosis in farmed Atlantic salmon, and despite huge numbers of flagellates in the vasculature, the tissues of the organs were remarkably unaffected. The relatively few gross and histopathological lesions may indicate that Arctic char are more tolerant to this parasite than Atlantic salmon.  相似文献   
8.
Preparation and lipase-catalyzed enantiotope selective acetylation of the prochiral 2-acyloxypropane-1,3-diols (1a–h) including sulfonic ester (1a–c) and carboxylic ester (1d–h) series is described. A strong influence of the acyl moiety in these diols on the enantiotope selectivity of the porcine pancreatic lipase (PPL)-catalyzed reaction with vinyl acetate was observed. The best results were achieved with the 2-(4-methylbenzoyl)oxy- and cyclohexanecarbonyloxypropane-1,3-diols (1g and 1h) resulting in acetylated products (2g) of ≥98% e.e. in 77% yield and (2h) of 95% e.e. in 66% yield, respectively.  相似文献   
9.
To identify specific mutants for components of phytochrome A (phyA) signaling in Arabidopsis, we established a light program consisting of multiple treatments with alternating red and far-red light. In wild-type seedlings, irradiation with multiple red light pulses can reduce the amount of phyA, which in turn decreases the high-irradiance responses (HIRs) mediated by the subsequent treatments with far-red light. Our mutants were able to avoid this red light-dependent reduction of the HIR. Here, we describe eid1, a new recessive mutant with increased sensitivity to far-red light. The eid1 mutation maps to the top of chromosome 4. The mutants showed no change in phenotype in darkness or under continuous white light, but they exhibited an increased sensitivity to red light and an increased persistence of HIR during prolonged dark phases after multiple short pulses of far-red light. The eid1 seedlings accumulated normal amounts of phytochrome and showed no alterations in the degradation or de novo synthesis of phyA. The expression of the Eid1 phenotype requires the presence of phyA. Our data provide evidence that EID1 is a negatively acting component in the phyA-dependent HIR-signaling pathway.  相似文献   
10.
Salmonella enterica serovar Agona is an important zoonotic pathogen, causing serious human illness worldwide, but knowledge about its genetics and evolution, especially regarding the genomic events that might have contributed to the formation of S . Agona as an important pathogen, is lacking. As a first step toward understanding this pathogen and characterizing its genomic differences with other salmonellae, we constructed a physical map of S . Agona in strain SARB1 using I-CeuI, XbaI, AvrII and Tn 10 insertions with pulsed-field gel electrophoresis techniques. On the 4815-kb genomic map, we located 82 genes, revealed one inversion of about 1000 kb and resolved seven deletions and seven insertions ranging from 10 to 67 kb relative to the genome of Salmonella typhimurium LT2. These genomic features clearly distinguish S . Agona from other previously analyzed salmonellae and provide clues to the molecular basis for its genomic divergence. Additionally, these kinds of physical maps, combined with emerging high-speed sequencing technologies, such as the Solexa or SOLiD techniques, which require a pre-existing high-resolution physical map such as the S . Agona map reported here, will play important roles in genomic comparative studies of bacteria involving large numbers of strains.  相似文献   
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