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A total of 189 strains of S. aureus isolated from cows, sheep, swines, poultry, monkeys, rabbits, foxes, and humans and 23 strains of S. intermedius isolated from minks and sables were studied. The staphylococci belonged to different biological types (according to the Hajek-Marsalek's scheme) and ecovars (according to the Meyer-Witte's scheme). The strains were studied with respect to their resistance to 10 antibiotics (benzylpenicillin, streptomycin, tetracycline, levomycetin, erythromycin, oleandomycin, neomycin, kanamycin, monomycin, and novobiocin), mercuric chloride and cadmium sulfate. As a whole the frequency of resistance to the above preparations among the staphylococci of the animal origin was not high. Differences in the frequency and range of the resistance between strains belonging to different biological types (ecovars) were shown. The highest number of the resistant cultures was detected among the strains of the biological type E (ecovar canis) and atypical strains of S. intermedius isolated from the minks. The least number of the resistant cultures was detected among the strains of the biological type C1 (ecovar bovis) isolated from the cows. It was found that almost all strains of S. intermedius were resistant to cadmium sulfate. This may be used as an additional characteristic of the species.  相似文献   

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This study investigated the physiological reactions of companion dogs (Canis familiaris) used in animal-assisted activities and animal-assisted therapy by measuring salivary cortisol concentrations. The dog caregivers (owners) collected saliva samples (a) at 3 control days without therapeutic work, (b) directly before and after each therapeutic session during 3 consecutive months, and (c) again at 3 control days without therapeutic work. The study used an enzyme immunoassay to analyze the samples. Cortisol concentrations were significantly higher during therapy days than on control days. Dogs working during the first half of the day produced higher cortisol concentrations after therapeutic sessions than before, whereas dogs working in the afternoon produced lower cortisol concentrations. Cortisol concentrations were higher in short sessions than in long ones and increased relative to the number of therapeutic sessions done during the sampling period. The results indicate that therapeutic work was physiologically arousing for the dogs in this study. Whether these physiological responses are indicative of potentially negative stress or of positive excitement remains an open question.  相似文献   

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In the paper we investigate how owner personality, attitude and gender influence dog behavior, dyadic practical functionality and the level of dog salivary cortisol. In three meetings, 12 female and 10 male owners of male dogs answered questionnaires including the Neo-FFI human personality inventory. Their dyadic behavior was video-taped in a number of test situations, and saliva samples were collected. Owners who scored highly in neuroticism (Neo-FFI dimension one) viewed their dogs as social supporters and spent much time with them. Their dogs had low baseline cortisol levels, but such dyads were less successful in the operational task. Owners who scored highly in extroversion (Neo-FFI dimension two) appreciated shared activities with their dogs which had relatively high baseline cortisol values. Dogs that had female owners were less sociable-active (dog personality axis 1) than dogs that had male owners. Therefore, it appears that owner gender and personality influences dyadic interaction style, dog behavior and dyadic practical functionality.  相似文献   

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We have constructed three cDNA clones of encephalomyocarditis virus strain R (EMCV-R) with poly(C) tracts of C4, C9, and C20. RNA transcribed from these cDNAs was infectious to HeLa cells, and the resultant viruses grew well in this system, albeit with plaque sizes that were proportional to the poly(C) length. When injected into mice, the progeny viruses were only slightly less pathogenic than EMCV-R, and the observed degree of attenuation was not nearly as dramatic as for equivalent mengoviruses with similar short poly(C)s. Short-tract poly(C)-mediated attenuation is therefore highly dependent on viral genomic context.  相似文献   

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Among Bacteria the carA and carB genes encoding the small (CarA) and large (CarB) subunits of carbamoylphosphate synthase (CPS) have been lost in certain symbionts (Haemophylus influenzae) and in most obligate intracellular parasites (Chlamydiae, Spirochaetes, Mycoplasmatales, Rickettsiae) having genome sizes in the 0.7- to 1.1-Mb range. Compared to Bacteria, Archaea exhibit a more varied pattern of CPS gene losses and an unusual propensity to incorporate CPS genes derived from both Bacteria and other Archaea. Schematically they fall into three groups. Group 1 taxa (the crenarchaeon Aeropyrum pernix and the euryarchaea Pyrococcus horikoshi and Pyrococcus abyssii) lack CPS genes altogether. Group 2 taxa (comprising Halobacteriales, Thermoplasmales, Methanococcales, Methanomicrobiales, Archaeoglobales) harbor CPS genes whose encoded CarB and CarA subunit proteins are ostensibly bacterial in origin; that is, they are intermixed with bacterial homologues on a phylogeny of concatenated CarA and CarB sequences and are not distinguishable from bacterial sequences after searching for domain-specific amino acid residue positions. Group 3 taxa (the crenarchaea Pyrobaculum aerophilum, Sulfolobus solfataricus, and Sulfolobus tokodaii and the euryarchaeon Pyrococcus furiosus) harbor CPS genes whose encoded proteins appear to be archaeal: consistent with an archaeal origin, the CarA and CarB sequences in this group possess both unique signatures and signatures affiliating them to Eukarya. Based on the topology of the clade comprising the four Group 3 taxa, we argue that CPS genes of P. furiosus (a euryarchaeon) and those of the crenarchaea P. aerophilum, S. solfataricus, and S. tokodaii are of a single type, resulting from the two genes being laterally transferred from a crenarchaeon to P. furiosus.  相似文献   

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Previously, the relevance of lipoproteins and their receptors has mainly been discussed in terms of cholesterol clearance in the adult organism. Now, findings from nematodes to fruit flies to mammals all point towards novel and unexpected roles for lipoprotein metabolism in the control of key regulatory pathways in the developing embryo, including signaling through steroid hormones and throughout the hedgehog and Wnt signaling pathways. Here, we discuss the emerging view of how lipoproteins and their receptors regulate embryogenesis.  相似文献   

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1. Migratory waterbirds are major vectors for the dispersal of aquatic plants. However, quantitative field studies of the frequency of transport are scarce, and the relative importance of internal and external transport remains unclear. 2. We quantified and compared the rates of internal and external transport of aquatic plant propagules by teal (Anas crecca) in the Camargue (southern France), inspecting the lower gut contents of birds that had been shot (n = 366) and washing birds that had been live‐trapped (n = 68) during the winters of 2006–2007 and 2007–2008. 3. Intact propagules (n = 902) of 21 plant taxa were recorded in the rectum of teal, of which 16 germinated or were shown to be viable. Intact propagules were recorded in the rectum of 20% of teal, with up to 171 propagules per individual bird. Chara oogonia were most abundant (60% of intact propagules), suggesting that small size favours internal transport. Eleocharis palustris, Juncus spp. and Potamogeton pusillus (17, 7 and 6% of intact propagules, respectively) were also very abundant. 4. Intact propagules (n = 12) of 10 plant taxa were found on the outside of live teal, and four of these taxa later germinated. Intact propagules were found on 18% of teal. No teal was found to carry more than one propagule externally. There was no difference in size between propagules transported internally and externally. 5. Teal are major dispersers of plants within the Camargue, despite being highly granivorous. Contrary to widespread assumptions in the literature, endozoochory by ducks appears to be a much more important mode of dispersal for aquatic plants than exozoochory. We found no evidence of changes in the probability of plant propagule dispersal at a landscape scale over the course of the winter, so propagule production and zoochory appear to be decoupled over time in aquatic systems.  相似文献   

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Aims: To investigate the distribution of staphylococcal enterotoxin genes (se) and the molecular features of community‐associated methicillin‐sensitive/resistant Staphylococcus aureus (CA‐MSSA/MRSA) isolates in the nostrils of healthy pets and their owners. Methods and Results: A total of 114 Staph. aureus isolates were identified from 1563 nasal swab samples, and CA‐MRSA accounted for 20·2% (n = 23) of the total identified isolates. CA‐MRSA isolates (91·3%, 21/23) harboured higher percentage of se than did CA‐MSSA isolates (58·2%, 53/91) (P < 0·01), and the two highest se profiles of CA‐MRSA were sebsekseq (42·9%, 9/21) and sebsekseqsep (28·6%, 6/21). Of the MSSAs, 42·8% (39/91) were resistant to at least one antimicrobial drug and 8·8% (8/91) were multidrug resistant (MDR). We identified nine staphylocoagulase (SC) types (I–VIII and X) and three multilocus sequence types (ST59‐MRSA‐IV/V, ST‐239‐MRSA‐V and ST241‐MRSA‐V). SC VII (23·4%, 22/94), a staphylococcal food poisoning isolate found mainly in Japan, and ST‐59‐MRSA‐IV/V (85%, 17/20), a widespread CA‐MRSA clone found mainly in Taiwan, both were the most predominant types. Phylogenetic analysis together with se and molecular characteristics obtained using pulsed‐field gel electrophoresis showed that high levels of antimicrobial resistance and the se‐carrying clone ST59‐MRSA‐IV/V‐SC VII were all clustered in genogroup 5. Conclusions: The CA‐MRSA clone of se‐carrying‐MDR‐ST‐59‐IV/V‐SC VII was identified predominantly in this study, and this clone might play a significant role in staphylococcal food poisoning in community settings. Significance and Impact of the Study: To our knowledge, this is the first study focussing on enterotoxin‐carrying CA‐MRSA/MSSA in pets and their owners, and the results support the future warnings in animal–human bond caused by CA‐staphylococci in the commonwealth and the need to take cautions worldwide.  相似文献   

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Background  

Depressive disorders are frequent in epilepsy and associated with reduced seizure control. Almost 50% of interictal depressive disorders have to be classified as atypical depressions according to DSM-4 criteria. Research has mainly focused on depressive symptoms in defined populations with epilepsy (e.g., patients admitted to tertiary epilepsy centers). We have chosen the opposite approach. We hypothesized that it is possible to define by clinical means a subgroup of psychiatric patients with higher than expected prevalence of epilepsy and seizures. We hypothesized further that these patients present with an Acute Unstable Depressive Syndrome (AUDS) that does not meet DSM-IV criteria of a Major Depressive Episode (MDE). In a previous publication we have documented that AUDS patients indeed have more often a history of epileptic seizures and abnormal EEG recordings than MDE patients (Vaaler et al. 2009). This study aimed to further classify the differences of depressive symptoms at admittance and follow-up of patients with AUDS and MDE.  相似文献   

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Coilin, more than a molecular marker of the cajal (coiled) body   总被引:5,自引:0,他引:5  
The Cajal (coiled) body is a discrete nuclear organelle that was first described in mammalian neurons in 1903. Because the molecular composition, structure, and function of Cajal bodies were unknown, these enigmatic structures were largely ignored for most of the last century. The Cajal body has now regained the interest of biologists, due to the isolation of a protein marker, coilin. Despite current widespread use of coilin to identify Cajal bodies in various cell types, its structure and function are still little understood. Here, I would like to discuss what we have learned about coilin and suggest a possible role for coilin in RNA processing and cellular trafficking, especially in relation to Cajal bodies and nucleoli. Although coilin has been investigated primarily in somatic cells, I will emphasize the advantages of using the amphibian oocyte to study nuclear proteins and organelles.  相似文献   

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Aim  The establishment success of exotic species is calculated as the fraction of introduced species that have become established, and invasion success is estimated as the fraction of established species that have spread significantly from their points of introduction. Records on species introductions are highly incomplete, so strong conclusions about the tens rule and invasibility of island and continents cannot be drawn.
Location  Global.
Methods  Using Jeschke (2008) as an example, we explain the issue of the inadequacy of data to draw conclusions about the tens rule and invasibility of island and continents.
Results  Lack of adequate data.
Main Conclusion  Jeschke (2008) probably overestimates the establishment and invasion success rates, so his conclusions about violation of the tens rule and that islands are not more susceptible to invasion than continents are misleading.  相似文献   

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Background  

Salmonella enterica serovar Typhimurium (Typhimurium) is an important pathogen that infects a broad range of hosts. In humans, Typhimurium causes a gastroenteritis characterized by vomiting, diarrhea, and abdominal pains. Typhimurium infection occurs mainly through the ingestion of contaminated food including poultry, pork, eggs, and milk. Chickens that are asymptomatic carriers of Typhimurium constitute a potential reservoir for infection. The type three secretion systems encoded by Salmonella pathogeniCity islands (SPI) 1 and 2 are major virulence factors of Salmonella. However, only a few studies have investigated their role during the infection of chickens.  相似文献   

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Plants have evolved several anti‐herbivory strategies, including direct defences, such as mechanical and chemical defences, and indirect or biotic defences, such as the recruitment of defending animals. We examined whether the investment plants make in direct defences differs between those which do and do not invest in biotic defences, by comparing standing herbivory and palatability of congeneric species with and without indirect defences at two ontogenetic stages: before and after the onset of indirect defences. We used Cordia alliodora and Croton suberosus as the species with indirect defences and Cordia elaeagnoides and Croton pseudoniveus as the species without indirect defences. We predicted that herbivores would prefer to eat species and stages with indirect defences to those without them. As predicted, we found that herbivores preferred species and ontogenetic stages with indirect defences in all cases. Overall, however, natural levels of herbivory were lower in species with indirect defences. We conclude that indirect defences offer effective protection against herbivores and posit that their recruitment allows plants to reduce investment in other defence mechanisms. Our results support the notion that plants trade‐off between direct and indirect defensive strategies. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 536–543.  相似文献   

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