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排序方式: 共有771条查询结果,搜索用时 15 毫秒
81.
82.
José Maria Villela Pádua Kaio Olímpio Das Graças Dias Maria Marta Pastina João Cândido de Souza Valéria Aparecida Vieira Queiroz Rodrigo Veras da Costa Maria Beatriz Pereira da Silva Carlos Alexandre Gomes Ribeiro Claudia Teixeira Guimarães Salvador Alejandro Gezan Lauro José Moreira Guimarães 《Euphytica》2016,211(3):277-285
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86.
Alexandre Olvera Maria Ballester Miquel Nofrar��as Marina Sibila Virginia Aragon 《Veterinary research》2009,40(3)
Haemophilus parasuis is a colonizer of the upper respiratory tract of healthy pigs, but virulent strains can cause a systemic infection characterized by fibrinous polyserositis, commonly known as Glässer’s disease. The variability in virulence that is observed among H. parasuis strains is not completely understood, since the virulence mechanisms of H. parasuis are largely unknown. In the course of infection, H. parasuis has to survive the host pulmonary defences, which include alveolar macrophages, to produce disease. Using strains from different clinical backgrounds, we were able to detect clear differences in susceptibility to phagocytosis. Strains isolated from the nose of healthy animals were efficiently phagocytosed by porcine alveolar macrophages (PAM), while strains isolated from systemic lesions were resistant to this interaction. Phagocytosis of susceptible strains proceeded through mechanisms independent of a specific receptor, which involved actin filaments and microtubules. In all the systemic strains tested in this study, we observed a distinct capsule after interaction with PAM, indicating a role of this surface structure in phagocytosis resistance. However, additional mechanisms of resistance to phagocytosis should be explored, since we detected different effects of microtubule inhibition among systemic strains. 相似文献
87.
Andr M. Almeida Alexandre Campos Sofia van Harten Luís Alfaro Cardoso Ana Varela Coelho 《Research in veterinary science》2009,87(2):196-199
In several laboratory and production species, the establishment of a proteome reference map of a specific tissue has been accomplished. The rabbit is widely used as both a production and experimental animal. A lot of physiology research involving the gastrocnemius muscle of rabbit is described, although no reference proteome map is available. In this work, the first reference map of the rabbit’s gastrocnemius muscle using 2D gel electrophoresis and the identification of proteins through peptide mass fingerprinting (PMF) was established. A total of 45 proteins were localized and identified with three major roles: cell structure and contractile apparatus; metabolic and cell defense proteins. A reference map of major proteins expressed is described enabling possible comparisons with other physiological studies. 相似文献
88.
Cristiano G. Pereira Alexandre L.N. Silva Patrícia de Castilhos Eneida C. Mastrantonio Richard A. Souza Raquel P. Romo Renata J. Rezende Janethe D.O. Pena Marcelo E. Beletti Maria A. Souza 《Veterinary parasitology》2009,165(3-4):231-240
The aim of this study was to evaluate the histopathological features in tissues of mice infected by human isolates (I, II, and III) or the reference M2903 strain of Leishmania braziliensis complex. BALB/c and C57Bl/6 mice were infected in the hind footpad with 106 stationary-phase promastigotes of L. braziliensis complex. The evolution of lesions was observed for 10 weeks and the animals were then euthanized and liver, spleen and popliteal lymph nodes were collected. Tissues were stained with hematoxylin and eosin and analyzed by immunohistochemistry assay. Increased thickness of infected footpads was observed in all animals, lesions were nodular and non-ulcerated. Mice infected with isolate I presented inflammatory infiltrates consisting predominantly of mononuclear cells in all tissues examined, and also a great number of megakaryocytes, compared with other isolates. Infection with isolate II led to an infected footpad enlargement not seen in other isolates. In addition, mononuclear infiltrates in the liver and hemosiderin in spleen were noted. Conversely, mice infected with either isolate III or M2903 strain only showed an increased number of megakaryocytes in spleen. All tissues examined had detectable amastigote forms of Leishmania by immunohistochemistry in all groups. Taking together, our results showed an unforeseen behavior of different isolates of L. braziliensis complex that led to diverse pathological findings. 相似文献
89.
Julie Gombert Frédérik Le Dily Jérémy Lothier Philippe Etienne Laurence Rossato Jean‐Michel Allirand Alexandra Jullien Alexandre Savin Alain Ourry 《植物养料与土壤学杂志》2010,173(6):875-884
In order to optimize nitrogen (N) fertilization and to reduce the environmental impact of oilseed rape without decreasing yield, a clearer understanding of N dynamics inside the plant is crucial. The present investigation therefore aimed to study the effects of different N‐application rates on the dynamics of N uptake, partitioning, and remobilization. The experiment was conducted on winter oilseed rape (Brassica napus L. cv. Capitol) under three levels of N input (0, 100, and 200 kg N ha–1) from stem elongation to maturity using 15N‐labeling technique to distinguish between N uptake and N retranslocation in the plant. Nitrogen fertilization affected the time‐course of N uptake and also the allocation of N taken up from flowering to maturity. Most pod N came from N remobilization, and leaves accounted for the largest source of remobilized N regardless the N‐application rate. However, the contribution of leaves to the remobilized N pool increased with the N dose whereas the one of taproot decreased. Stems were the main sink for remobilized N from stem elongation to flowering. Leaves remained longer on N200 than on N0 and N100 plants, and N concentration in fallen leaves increased with the N treatment and in N100 plants along an axial gradient from the basal to the upper leaves. Overall, these results show that the timing of N supply is more crucial than the N amount to attain a high N efficiency. 相似文献
90.
In dogs with neurological disturbances without myoclonus and extraneural signs, the clinical diagnosis of distemper is difficult
perform. Considering the great infectious potential of the disease, the possibility of carrying out an antemortem diagnosis
of distemper is important, particularly in hospitalized patients with neurological disease. The present study was carried
out to evaluate RT-PCR for antemortem CDV detection in hospitalized dogs with neurological disturbances without the typical
findings of distemper. We investigated five dogs with canine distemper virus (CDV) encephalomyelitis, in which the clinical
diagnosis was not performed owing to the absence of characteristic signs of the disease, such as myoclonus and systemic signs.
We observed an apparent high sensitivity of RT-PCR in urine samples for detection of CDV: four out of five urine samples were
RT-PCR positive. The results of the present study suggest that urine is a good biological sample for antemortem CDV detection
by RT-PCR in dogs with distemper encephalomyelitis in which the clinical diagnosis is likely to be difficult owing to the
absence of suggestive distemper signs. The use of two different body fluids (urine and CSF) may increase the RT-PCR sensitivity
for antemortem diagnosis of distemper in such cases. 相似文献