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991.
Souza AP Guerrero PN Nishimori CT Paula DP Santos PS de Rezende ML Nunes N 《Journal of Feline Medicine and Surgery》2005,7(2):95-100
The cardiopulmonary effects of desflurane and sevoflurane anesthesia were compared in cats breathing spontaneously. Heart (HR) and respiratory (RR) rates; systolic (SAP), diastolic (DAP) and mean arterial (MAP) pressures; partial pressure of end tidal carbon dioxide (PETCO2), arterial blood pH (pH), arterial partial pressure of oxygen (PaO2) and carbon dioxide (PaCO2); base deficit (BD), arterial oxygen saturation (SaO2) and bicarbonate ion concentration (HCO3) were measured. Anesthesia was induced with propofol (8+/-2.3mg/kg IV) and maintained with desflurane (GD) or sevoflurane (GS), both at 1.3 MAC. Data were analyzed by analysis of variance (ANOVA), followed by the Tukey test (P<0.05). Both anesthetics showed similar effects. HR and RR decreased when compared to the basal values, but remained constant during inhalant anesthesia and PETCO2 increased with time. Both anesthetics caused acidemia and hypercapnia, but BD stayed within normal limits. Therefore, despite reducing HR and SAP (GD) when compared to the basal values, desflurane and sevoflurane provide good stability of the cardiovascular parameters during a short period of inhalant anesthesia (T20-T60). However, both volatile anesthetics cause acute respiratory acidosis in cats breathing spontaneously. 相似文献
992.
To determine the prevalence of Neospora caninum antibodies and associated factors, blood sera from 623 female dairy cattle from 23 farms in the north of the state of Paraná, Brazil, were analyzed by means of the indirect immunofluorescent-antibody test (IFAT > or = 25). Serum samples from 134 dogs living on the same farms also were tested for N. caninum antibodies (IFAT > or = 50), and the presence of dogs was associated with the prevalence of N. caninum antibodies in cattle. The overall seroprevalence in cattle was 14.3%, mainly in animals over 24 months of age. Seroprevalence in Holsteins (15.1% of 558) was greater than in mixed-breed cattle (7.7% of 65). Age (> or =24 months) of cattle, feeding silage and/or concentrate produced on the farm were associated; antibodies were found in 21.6% of dogs; and the presence of dogs was associated with the prevalence of N. caninum antibodies in cattle. 相似文献
993.
Fernandes BC Gennari SM Souza SL Carvalho JM Oliveira WG Cury MC 《Veterinary parasitology》2004,123(1-2):33-40
In Brazil there are few reports on the prevalence of anti-Neospora caninum antibodies in dogs from urban, periurban and rural areas. Serum samples from 450 dogs, 300 from urban, 58 from periurban and 92 from rural areas, were tested for the detection of anti-N. caninum IgG antibodies using IFAT: indirect fluorescent antibody test (IFAT, > or =50). Antibodies were observed in 63 (14%) of the 450 serum samples analyzed, with 32 (10.7%) in dogs coming from the urban area, 11 (18.9%) from the periurban area and 20 (21.7%) from the rural area. Statistical differences were seen between the occurrences in animals from the urban area and those of the rural area (P = 0.01). The antibody titers found were: 1:50 in 20 dogs, 1:100-1:800 in 41 dogs, and 1:3200 in two dogs. In the female dogs, a smaller prevalence of dogs with antibodies was observed in those from the urban area (7.5%) in comparison with those of the rural (21.0%) (P = 0.05) and periurban (23.3%) (P = 0.01) areas. There were growing levels of antibody prevalence with the increase in age of the dogs in all three areas studied. Although this increase was not significant, it indicates a tendency towards more infections with age, suggesting post-natal exposure to N. caninum. However, a significant difference (P = 0.05) was observed in the occurrence of anti-N. caninum antibodies in dogs with ages = 2 years in urban (13.1% urban) versus rural environments (27.1% rural). Among the other age brackets studied the difference was not significant. The results confirm the presence of N. caninum in the region and reveal the important role of dogs in the parasite's epidemiology. 相似文献
994.
The interaction of the tachyzoite stage of Toxoplasma gondii with neutrophils was investigated. Morphological aspects of the initial moments of interaction were analyzed by transmission and scanning electron microscopy, revealing at least three types of reaction from the leukocytes to the parasite: the projection of filopodia, formation of a tunnel-like projection involving the parasite, and invagination of the leukocyte surface at the point of entry. The influence on infectivity of tyrosine kinase, phosphokinase C and phosphatidylinositol 3 kinase cell signaling pathways were studied with the aid of drugs affecting these enzymes in these cells. 相似文献
995.
Ribeiro AA Elias CF Liberti EA Guidi Wde L de Souza RR 《Anatomia, histologia, embryologia》2002,31(6):344-349
A number of neurons of the autonomic nervous system are situated in the ganglia and can be systematically divided into pre-vertebrals, paravertebrals, intramural and para-viscerals. The celiac-mesenteric ganglion, an important pre-vertebral ganglion, is located together with the abdominal aorta and links the central nervous system to the peripheral system, participating in the coordination of peripheral reflexes and principally innervating the stomach, intestines, accessory glands (liver and pancreas). In addition, the celiac-mesenteric ganglion also contributes to the innervation of the spleen and has a role in gastrointestinal motility control. This study examined the structural and ultrastructural aspects of 40 celiac-mesenteric ganglia from domestic dogs. For light microscopy ganglia were included in paraplast and stained with haematoxylin-eosin, picrosirius, toluidine blue, Calleja's and Masson's trichrome. For examination by electron microscopy, the ganglia were submitted to cryofracture, enzyme digestion, hydrolysis and fixed in 5% glutaraldehyde in 0.1 M phosphate buffer (pH 7.4). The celiac-mesenteric ganglion was observed as a ganglionic complex composed of various ganglionic units separated by types I and III collagen fibres, predominantly unmyelinated nerve fibres and continuous capillaries. This complex is surrounded by a double-layer capsule (internal and external). The principal ganglion cells had eccentric nuclei with two nucleoli, the nucleolemma was double and presented nuclear pores. In the cytoplasm there were vesicles of the Golgi apparatus, electron-dense vacuoles, mitochondrias, smooth and granulated endoplasmic reticulum and free ribosomes. In conclusion, this ganglionic complex, in contrast to similar structures in the enteric nervous system, presents separate ganglionic units in a systematic arrangement related to the extrinsic and specific innervation of the target organs. 相似文献
996.
997.
Dirceu Macagnan Reginaldo da S. Romeiro Jorge T. de Souza Alan W. V. Pomella 《Phytoparasitica》2006,34(2):122-132
In this study, actinomycetes and endospore-forming bacteria were isolated from the surface of cacao pods. The activity of
these microorganisms againstCrinipellis perniciosa andPhytophthora palmivora, causal agents of witches’ broom and black pod diseases of cacao, respectively, was investigated. A total of 336 isolates
of actinomycetes and endosporeforming bacteria were tested on a detached pod assay againstC. perniciosa. The screening procedure used proved to be fast and inexpensive, allowing the selection of five actinomycetes as the most
promising isolates for the biocontrol ofC. perniciosa. Under laboratory conditions the actinomycetes were able to inhibit 100% ofC. perniciosa basidiospore germination. However, under field conditions the selected actinomycetes were unable to protect cacao pods against
both pathogens. In these experiments, inhibition ofC. perniciosa ranged from 6% to 21% in relation to the control, whereas there was no inhibition of black pod caused byP. palmivora. Formulations need to be improved in order to enhance the activity of the actinomycetes against cacao pathogens in the field.
Molecular identification of the selected isolates showed that they are species of the genusStreptomyces. 相似文献
998.
Guy de Capdeville Manoel Teixeira Souza Jr. Jansen Rodrigo Pereira Santos Simone de Paula Miranda Alexandre Rodrigues Caetano Fernando Araripe Gonçalves Torres 《Scientia Horticulturae》2007
Anthracnose, caused by Colletotrichum gloeosporioides, is a major post-harvest disease in papaya fruit. The major objectives of the present work were to isolate, select and test the in vitro and in vivo ability of epiphytic microorganisms, isolated from papaya fruit and leaf surfaces, in controlling anthracnose onset after harvest. A total of 75 bacteria, 67 yeasts and 22 mycelial fungi were isolated. Thirty yeast isolates were able to inhibit the mycelial growth of C. gloeosporioide in vitro and seven of those were used in in vivo assays, resulting in the identification of two very effective isolates. Isolate CEN63, identified molecularly as Cryptococcus magnus, was the most effective in controlling the disease and therefore was studied in more detail. The results of the assays with C. magnus provided evidence that when fruit were treated with the antagonists at concentrations of 107 to 108 cells/ml, as early as 24 h, preferentially 48 h, before inoculation with the pathogen, the development of disease was significantly reduced. C. magnus is a potential antagonist for the development of a commercial product. Additional studies on the modes of action of this yeast isolate, as on its ability to interact with fungicides are being conducted to generate solid basis for the development of an environmentally friendly control agent. 相似文献
999.
Oliveira AA Mota RA Pereira GC Langoni H Souza MI Navegantes WA Sá ME 《The Onderstepoort journal of veterinary research》2001,68(4):275-279
The prevalence of Leptospira interrogans serovars in dairy cattle was determined by analyzing 464 serum samples from cows on 15 properties in Garanhuns municipal district, Pernambuco State, Brazil. A microscopic seroagglutination test including 12 serovars of Leptospira interrogans as antigens was used. Samples with titres 100 were considered positive. Two hundred and twenty-one (47.63%) of the samples were positive to one or more serovars. The prevalence of the serovars was hardjo (21.98%), bratislava (15.73%), castellonis (11.64%), tarassovi (10.56%), pyrogenes (1.72%), icterohaemorrhagiae (1.08%), pomona (0.86%), wolffi (0.86%), grippotyphosa (0.86%), djasiman (0.43%), canicola (0.21 %), and copenhageni (0.21%). 相似文献
1000.
Sara Maria Chalfoun Samantha Brettas Oliveira Igor Chalfoun Fernanda Carvalho Costa Eliane Maria De Souza Xisto 《农业科学与技术》2013,(9):689-696
Tbio is a start-up created to give support to commercialize the products of the biofactory installed in the Federal University of Lavras, Minas Gerais State, Brazil, part of the Innovation Program developed by this University. Its specialty is to innovate, through biological solutions with the vision of the future, once there is a strong demand of food and beverages free of chemical residues and with lower employing of these substances along the production chain by several consumers. The innovative products are generated from microorganisms tested regarding its capacity to promote yield protection, pests and disease control, acceleration of the desmucilage waste water treatment, and improvement of process of faster solubilization, that depends on natural phosphate fertilizers. The goal of this article is to approach the activities that have been developed in this start-up and the knowledge about biocontrol and natural antimicrobials produced by fungi resulting in innovative products to attend the world claim for products free of chemical residues of any kind and harmless to the consumers, environment and workers. 相似文献