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81.
Thirty isolates of Magnaporthe grisea collected from 18 provinces/cities representing 21 pathotypes and 9 different lineages were inoculated to rice varieties with known resistance genes and some hybrid rices,conventional early indica and late japonica varieties cultivated recently in China.Virulence spectrum of the 30 isolates was very different,showing that they recognize numerous different resistance genes.Varieties also revealed very different resistance patterns showing that they carry different resistance genes or combinations of resistance genes.On the basis of comparisons with international differential varieties with known resistance genes,resistance genes in certain Chinese varieties could be speculated.The results indicated that some of them were resistant to most of the isolates tested and that they could be of interest as resistance sources for hybrid parents or to be planted in the field directly.  相似文献   
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83.
Rickettsioses and bartonelloses are arthropod-borne diseases of mammals with widespread geographical distributions. Yet their occurrence in specific regions, their association with different vectors and hosts and the infection rate of arthropod-vectors with these agents remain poorly studied in South-east Asia. We conducted entomological field surveys in the Lao PDR (Laos) and Borneo, Malaysia by surveying fleas, ticks, and lice from domestic dogs and collected additional samples from domestic cows and pigs in Laos. Rickettsia felis was detected by real-time PCR with similar overall flea infection rate in Laos (76.6%, 69/90) and Borneo (74.4%, 268/360). Both of the encountered flea vectors Ctenocephalides orientis and Ctenocephalides felis felis were infected with R. felis. The degrees of similarity of partial gltA and ompA genes with recognized species indicate the rickettsia detected in two Boophilus spp. ticks collected from a cow in Laos may be a new species. Isolation and further characterization will be necessary to specify it as a new species. Bartonella clarridgeiae was detected in 3/90 (3.3%) and 2/360 (0.6%) of examined fleas from Laos and Borneo, respectively. Two fleas collected in Laos and one flea collected in Borneo were co-infected with both R. felis and B. clarridgeiae. Further investigations are needed in order to isolate these agents and to determine their epidemiology and aetiological role in unknown fever in patients from these areas.  相似文献   
84.
The stratum corneum (SC) forms the main part of the permeability barrier of the skin. In mice and in humans, cutaneous barrier disruption can be generated by removing the SC with tape stripping (TS) and the skin barrier function can be assessed by measurement of transepidermal water loss (TEWL). The aim of the present study was to characterize the skin barrier restoration in the dog following mechanical disruption and to analyse the correlation between the skin barrier recovery and TEWL measurement. Thirty sequential TS were performed on 12 sites on four healthy beagle dogs. The number of TS was chosen to ensure a sufficient barrier disruption with a slow recovery. Skin repair was assessed for 72 h by clinical and histological examinations, and TEWL measurements. The results showed that performing 30 TS was adequate to disrupt the skin barrier in the dog. The homeostatic repair response, initiated in the skin, was rapid and characterized by complete restoration of the SC within 72 h, accompanied by greater basal cell proliferation, and dermal eosinophilic inflammation. TEWL was significantly increased by complete removal of the SC but recovered along with restoration of the SC (Scheffe test, P ≤ 0.05). Characterization of a canine model of barrier disruption and restoration and assessment of the skin barrier function by TEWL measurements could help better understand the events implied in skin barrier function. Development of this canine model is also necessary for future studies on the effects of treatments aimed at restoring the skin barrier.  相似文献   
85.
Q fever     
Q fever is a zoonotic disease caused by the ubiquitous pathogen Coxiella burnetii responsible for acute and chronic clinical manifestations. Farm animals and pets are the main reservoirs of infection, and transmission to human beings is mainly accomplished through inhalation of contaminated aerosols. This illness is associated with a wide clinical spectrum, from asymptomatic or mildly symptomatic seroconversion to fatal disease. In humans Q fever can manifest as an acute disease (mainly as a self-limited febrile illness, pneumonia, or hepatitis) or as a chronic disease (mainly endocarditis), especially in patients with previous valvulopathy and to a lesser extent in immunocompromised hosts and in pregnant women. In contrast in animals, Q fever is in most cases, strikingly asymptomatic. The definite diagnosis of Q fever is made based on a significant increase in serum antibody titers, the determination of which often requires considerable time, and therefore patients must be monitored for a certain period. The treatment is effective and well tolerated, but must be adapted to the acute or chronic pattern with the tetracyclines to be considered the mainstay of antibiotic therapy. Several actions have been proposed to prevent and reduce the animal and environmental contamination. Vaccination of animals in infected flocks, as well as in uninfected ones close to them, with an efficient vaccine can prevent abortions and shedding of the bacteria.  相似文献   
86.
Cutaneous lupus erythematosus (CLE) is a rare immune‐mediated dermatitis. To the best of the authors’ knowledge it has not been described in donkeys. A 5‐year‐old male neutered donkey, living in south‐east France, was diagnosed with CLE. Clinical signs included generalized symmetrical areas of alopecia, erythema, crusting and scales. Diagnostic tests included examination of skin biopsy samples by histopathological and immunohistochemical analysis which demonstrated an interface dermatitis with CD8+ T cells. The skin condition was successfully treated initially with glucocorticoids and methotrexate; successful long‐term maintenance was associated with administration of methotrexate.  相似文献   
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88.
BACKGROUND: Pimobendan (PIMO) is an inodilator that may have some beneficial effects in canine degenerative mitral valve disease (MVD). However, little information is available about its cardiac effects in dogs without systolic myocardial dysfunction. HYPOTHESIS: Compared to benazepril (BNZ), an angiotensin-converting enzyme inhibitor, PIMO may worsen valve regurgitation in early canine MVD. ANIMALS: Twelve Beagles with asymptomatic MVD were randomized into 2 groups (n = 6) receiving BNZ or PIMO at dosages of 0.25 mg/kg PO q24h and q12h respectively, for 512 days. METHODS: The study followed a blinded, randomized, prospective, and parallel group design. After day 512, the dogs were necropsied, and cardiac histopathology was performed in a blinded manner. RESULTS: A significant treatment effect was observed as soon as day 15 with increased systolic function in the PIMO group by comparison to baseline value as assessed by fractional shortening (P < .0001) and tissue Doppler variables (P = .001). Concurrently, the maximum area and peak velocity of the regurgitant jet signal increased (P < .001), whereas these variables remained stable in the BNZ group. Histologic grades of mitral valve lesions were more severe in the PIMO group than in the BNZ group. Moreover, acute focal hemorrhages, endothelial papillary hyperplasia, and infiltration of chordae tendinae with glycosaminoglycans were observed in the mitral valves of dogs from the PIMO group but not in those of the BNZ group. CONCLUSIONS AND CLINICAL IMPORTANCE: PIMO has adverse cardiac functional and morphologic effects in dogs with asymptomatic MVD. Additional investigation in dogs with symptomatic MVD is now warranted.  相似文献   
89.
The murine norovirus (MNV) is a recently discovered mouse pathogen, representing the most common contaminant in laboratory mouse colonies. Nevertheless, the effects of MNV infection on biomedical research are still unclear. We tested the hypothesis that MNV infection could alter immune response in mice with acute lung infection. Here we report that co-infection with MNV increases survival of mice with Pseudomonas aeruginosa acute lung injury and decreases in vivo production of pro-inflammatory cytokines. Our results suggest that MNV infection can deeply modify the parameters studied in conventional models of infection and lead to false conclusions in experimental models.  相似文献   
90.
We report the molecular detection of several Bartonella species in 44 (21.5%) of 204 fleas from Algeria collected from 26 rodents and 7 hedgehogs. Bartonella elizabethae and B. clarridgeiae were detected in the fleas collected on hedgehogs. Bartonella tribocorum and B. elizabethae were detected in fleas collected from rats and mice, and sequences similar to an unnamed Bartonella sp. detected in rodents from China were detected in rats as well as a genotype of Bartonella closely related to Bartonella rochalimae detected in fleas collected on brown rats (Rattus norvegicus).  相似文献   
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