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排序方式: 共有101条查询结果,搜索用时 15 毫秒
1.
A Fernandez J Perez L Carrasco M J Bautista J M Sanchez-Vizcaino M A Sierra 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(6):393-402
Lymph nodes, spleen, liver, lung and kidney obtained from pigs experimentally infected with two African Swine Fever Virus (ASFV) isolates of differing virulence were fixed by perfusion with glutaraldehyde and embedded in paraffin. An immunoperoxidase technique using a polyclonal anti-ASFV serum was performed on tissue sections in order to detect ASFV antigen. The distribution of ASFV antigen in such infected organs is shown and the differences between both infections compared and discussed. Monocytes, macrophages, hepatocytes, endothelial cells, neutrophils and epithelial cells were found to contain ASFV antigens. 相似文献
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Fungal flora on cutaneous and mucosal surfaces of cats infected with feline immunodeficiency virus or feline leukemia virus 总被引:1,自引:0,他引:1
Sierra P Guillot J Jacob H Bussiéras S Chermette R 《American journal of veterinary research》2000,61(2):158-161
OBJECTIVE: To compare cutaneous and mucosal mycoflora in cats infected with FIV or FeLV with that in noninfected cats. ANIMALS: 85 client-owned cats; 24 seropositive for FIV, 10 seropositive for FeLV, 1 seropositive for both viruses, and 50 seronegative for both viruses. PROCEDURE: Cutaneous specimens were obtained from the coat and external acoustic meatus (ear canal) and mucosal specimens from the oropharynx and rectum. Fungi were isolated from specimens, using Sabouraud dextrose agar incubated at 27 or 37 C for cutaneous and mucosal specimens, respectively. RESULTS: Fungal colonies were cultured from at least 1 specimen from 83 of 85 (97.6%) cats. The most common fungal isolates were Aspergillus spp (cultured from 59.3% of all specimens), Penicillium spp (50.0%), Cladosporium spp (44.2%), Scopulariopsis spp (41.8%), and lipophilic yeasts of the genus Malassezia (31.4%). A greater diversity of fungal genera was isolated from retrovirus-infected cats, and Malassezia spp were more commonly recovered from these cats, compared with noninfected cats. Candida albicans, Cryptococcus neoformans, and dermatophytes (eg, Microsporum canis) were rarely isolated from any cat. Significant differences in frequency of isolation of C. neoformans and dermatophytes were not found between infected and noninfected cats. CONCLUSIONS AND CLINICAL RELEVANCE: Cats infected with FIV or FeLV may have a greater diversity of cutaneous and mucosal mycoflora than noninfected cats. However, infected cats may be no more likely than noninfected cats to expose humans to zoonotic fungi such as C. albicans, C. neoformans, and M. canis. 相似文献
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This paper summarizes several studies on N recycling in a tropical silvopastoral system for assessing the ability of the system
to increase soil fertility and insure sustainability. We analyzed the N2 fixation pattern of the woody legume component (Gliricidia sepium), estimated the recycling rate of the fixed N in the soil, and measured N outputs in tree pruning and cut grass (Dichanthium aristatum). With this information, we estimated the N balance of the silvopastoral system at the plot scale. The studies were conducted
in an 11-year-old silvopastoral plot established by planting G. sepium cuttings at 0.3 m × 2 m spacing in natural grassland. The plot was managed as a cut-and-carry system where all the tree pruning
residues (every 2-4 months) and cut grass (every 40-50 days) were removed and animals were excluded. No N fertilizer was applied.
Dinitrogen fixation, as estimated by the 15N natural abundance method, ranged from 60-90% of the total N in aboveground tree biomass depending on season. On average,
76% of the N exports from the plot in tree pruning (194 kg [N] ha–1 yr–1) originated from N2 fixation. Grass production averaged 13 Mg ha–1 yr–1 and N export in cut grass was 195 kg [N] ha–1 yr–1. The total N fixed by G. sepium, as estimated from the tree and grass N exports and the increase in soil N content, was about 555 kg [N] ha–1 yr–1. Carbon sequestration averaged 1.9 Mg [C] ha–1 yr–1 and soil organic N in the 0-0.2 m layer increased at a rate of 166 kg [N] ha–1 yr–1, corresponding to 30% of N2 fixation by the tree. Nitrogen released in nodule turnover (10 kg [N] ha–1 yr–1) and litter decomposition (40 kg [N] ha–1 yr–1) contributed slightly to this increase, and most of the recycled N came from the turnover or the activity of other below-ground
tree biomass than nodules.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
6.
Effects of three forage harvesting regimes-total removal of foliage and branches once (T-12) or twice a year (T-6) and 50% removal every 2 months (P-2)-on growth and biological dinitrogen fixation of Gliricidia sepium (Jacq.) Walp were studied under subhumid tropical conditions in Guadeloupe, French Antilles. Gliricidia sepium was grown in association with the perennial C(4) grass Dichantium aristatum (Poir) C.E. Hubbard in a two-storied fodder production system. The medium-term effects of pruning on N(2) fixation were assessed by the (15)N natural abundance method. Gmelina arborea Roxb. was used as the non-fixing reference. The trees in the T-12 regime followed the natural phenological cycle, and flowering and podfilling at the beginning of the dry season reduced both foliage and nodule biomass. The T-6 regime impeded flowering, and only a few flowers, on older branches, were produced in the P-2 regime. In trees in the T-12, T-6, and P-2 regimes, fixed N comprised 54-87, 54-92, and 60-87%, respectively, of the total N in aboveground biomass, depending on sampling date. Total annual accumulation of N in harvestable aboveground biomass was highest in trees in the T-6 regime at 313 kg ha(-1), of which 204 kg ha(-1) of N was fixed from the atmosphere. In all treatments, about 70% of the N exported per year from the plot in the fodder harvest came from N(2) fixation. Thus, N(2) fixation makes an important contribution to the N economy of the G. sepium-D. aristatum forage production system, and greatly reduces the need for fertilizer application. 相似文献
7.
J. Aguilar C. Dorronsoro E. Fernández J. Fernández I. García F. Martín M. Sierra M. Simón 《Water, air, and soil pollution》2007,180(1-4):109-118
In 1998, the pond containing the ore wastes from a pyrite mine in Aznalcóllar (SW, Spain) broke open, spilling some 36×105 m3 of acidic waters and 9?×?105 m3 of tailings containing high concentrations of As and heavy metals. The affected area was around 55 km2 of predominantly agricultural soils. After the clean-up of the tailings, many remediation actions were undertaken and the use of blocking agents to immobilize the As was one of the most extended measure. The first experiment performed was to determine the most important soil components in As adsorption under acidic conditions. A second experiment was conducted to neutralize the acidity caused by the solution coming from the tailings undergoing oxidation; an adequate liming material (sugar-refinery scum) was selected and the application rates were established. After the remediation measures, the zone was monitored for three years. A detailed study in four experimental plots located in the most polluted sector was carried out to test the influence of iron oxides in the As immobilization. The use of red soils of the area (rich in free-iron oxides Fed) was established as an appropriate material in the remediation of the area. 相似文献
8.
J. Hervás J. C. Gómez-Villamandos A. Méndez L. Carrasco M. A. Sierra 《Veterinary research communications》1996,20(3):285-299
African swine fever is a viral haemorrhagic disease of pigs which has been used as a model for the study of viral haemorrhagic diseases in man. The acute course of the disease is characterized by acute proliferative glomerulonephritis, with viral replication in mesangial cells and occasional focal necrosis of the renal tubular system; hyperplasia of the collecting ducts is associated with evident virus replication. Haemorrhages have been attributed to endothelial dysfunction, aggravated by virus replication in endothelial cells in the final stages of the disease. The renal interstitium displays intense oedema and an infiltrate largely composed of macrophages. Virus replication has also been observed in fibroblasts and in the smooth0muscle cells of arterioles and venules.In subacute-chronic forms of the disease, various types of glomerulonephritis are observed, ranging from mesangial proliferative glomerulonephritis to focal and segmental hyalinosis associated with immune-mediated phenomena. No striking changes are reported in the renal tubular system. Interstitial haemorrhages are associated with diapedesis due to immunologically mediated events. The interstitium has also been found to contain a lymphohistiocytic infiltrate with abundant plasma cells. No evidence has been reported of viral replication in any cell population.Abbreviations ASF
African swine fever
- ASFV
African swine fever virus
- C
complement component
- DNA
deoxyribonucleic acid
- HAD50
50% haemoadsorbing doses
- Ig
immunoglobulin
- MPS
mononuclear phagocytic system
- PAS
periodic acid-Schiff reagent 相似文献
9.
Sierra E Fernández A Espinosa de Los Monteros A Jaber JR Andrada M Herráez P 《Veterinary journal (London, England : 1997)》2012,193(1):152-156
Skeletal muscle samples were examined post-mortem in 148 cetaceans over a 12-year period. Histological analysis included haematoxylin and eosin (HE) and periodic acid-Schiff (PAS) staining with and without diastase digestion. In addition, histological muscle sections were immunostained for ubiquitin and fast and slow heavy-chain myosin isoforms. PAS-positive, diastase-resistant inclusions were detected in 26 animals from 11 different species. Older cetaceans were preferentially affected. These intrafibre inclusions varied from large aggregates to multiple coarse granules and were typically associated with type II fibres. All diastase-resistant inclusions were positive for ubiquitin. These features resembled those inclusions described as complex polysaccharide in horses. Based on these histological findings and the ubiquitin staining pattern, a morphological diagnosis of complex polysaccharide storage myopathy is proposed. 相似文献
10.
Precision Agriculture - This article describes the design and field evaluation of a low-cost, high-throughput phenotyping robot for energy sorghum for use in biofuel production. High-throughput... 相似文献