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61.
RT-PCR was used to detect canine distemper virus (CDV) RNA in clotted blood from Argentine domestic dogs. The NP gene was detected in 73 out of 99 blood samples analyzed. The deduced amino acid sequence of these gene fragments showed 100% identity with the sequence of other wild-type and vaccine strains. A fragment of the hemagglutinin gene was amplified from 24 (32.9%) of the NP-RNA-positive clinical specimens. These H fragments were further analyzed by restriction fragment length polymorphism (RFLP) and sequencing. A single NdeI site was detected in all 24 wild-type strains but was absent in the vaccine strains. Phylogenetic analysis of the partial hemagglutinin amino acid sequences showed close clustering for local strains, clearly distinct from vaccine strains and other wild-type foreign CDV strains. One of the local strains, Arg 23, branched out of the root of the Argentine clade, close to the European strains, suggesting that two different pathogenic CDV genotypes are currently circulating in Argentina, one of them clearly predominant.  相似文献   
62.
This study evaluated the performance of an immunochromatographic test (ICT) for the diagnosis of canine brucellosis caused by Brucella canis, comparing its results with that of the rapid slide agglutination test with and without the use of 2‐mercaptoethanol and the agar gel immunodiffusion test (AGID). The microbiological culture, PCR and clinical examination were used as reference. According to the results obtained in clinical examination, blood culture, culture of semen and vaginal swab and PCR in blood, semen and vaginal swab, a total of 102 dogs were divided into three groups: B. canis‐infected dogs (Group 1), B. canis‐non‐infected dogs (Group 2) and dogs with suspected brucellosis (Group 3). The diagnostic sensitivity of RSAT, 2ME‐RSAT, AGID and ICT in Group 1 was, respectively, 75%, 37.5%, 27.8% and 89.58%. The diagnostic specificity of RSAT, 2ME‐RSAT, AGID and ICT in Group 2 was, respectively, 91%, 100%, 100%, and 100%. In dogs with suspected brucellosis, 9.67% were RSAT positive, none was positive by 2ME‐RSAT, 3.22% were AGID positive and 6.45% were ICT positive. The main drawback concerning canine brucellosis diagnosis is the lack of a highly sensitive serological assay to be used as a screening test to the rapid identification of infected animals. The ICT showed a high diagnostic specificity and a diagnostic sensitivity value greater than that observed in the RSAT, 2ME‐RSAT and AGID. However, 10.41% of infected dogs had negative results by ICT. These dogs were positive by microbiological culture and/or PCR, indicating active infection and consequently a higher potential of spreading Brucella. Although rapid and simple to perform, the ICT lacked sensitivity to be used as a screening test.  相似文献   
63.
The fate of global soil carbon stores in response to predicted climate change is a ‘hotly’ debated topic. Considerable uncertainties remain as to the temperature sensitivity of non-labile soil organic matter (SOM) to decomposition. Currently, models assume that organic matter decomposition is solely controlled by the interaction between climatic conditions and soil mineral characteristics. Consequently, little attention has been paid to adaptive responses of soil decomposer organisms to climate change and their impacts on the turnover of long-standing terrestrial carbon reservoirs. Using a radiocarbon approach we found that warming increased soil invertebrate populations (Enchytraeid worms) leading to a greater turnover of older soil carbon pools. The implication of this finding is that until soil physiology and biology are meaningfully represented in ecosystem carbon models, predictions will underestimate soil carbon turnover.  相似文献   
64.

Purpose

This work explores the application of the use of Zn, Cu, and Pb relative contents as a new type of normalization method for geochemical properties of soils and sediments in an Atlantic Basin (Anllóns River, NW Spain). The method is based on the conservative behavior of these elements, which exhibit a certain concentration ratio that remains stable as long as there are no human disturbances.

Materials and methods

The average relative contents of Zn, Cu, and Pb were calculated by dividing the concentration of each metal in soils or sediments, in the <63-μm fraction, by the sum of Zn, Cu, and Pb, expressed as a percentage. The evaluation of the sum of the average relative concentrations of Zn, Cu, and Pb (Ri), together with three standard deviations for each element, namely, Ri ± 3Si, allows a hexagon to be constructed, represented in ternary diagrams of Zn:Cu:Pb. Following the method proposed by Weng et al. (Environ Geol 45:79–85, 2003), those samples falling outside the hexagon must be considered outliers.

Results and discussion

Results obtained confimed the conservative behavior between the relative contents of Zn, Cu, and Pb in surficial samples (soils, bed, and suspended sediments). Only sediment cores displayed nonconservative behavior, showing a marked Pb enrichment, with respect to the surficial samples. When Zn, Cu, and Pb relative contents were plotted in ternary diagrams, outliers were best classified when the hexagon was drawn with standard deviations of samples from the study area. The hexagon drawn with an international database of soils and sediments showed a poorer classification of outliers.

Conclusions

The results showed that total Zn, Cu, and Pb relative contents may be employed to investigate anthropogenic disturbances of these elements in soils and sediments of the Anllóns River Basin, thus corroborating that this type of normalization may be employed as a tool to assess outliers in a contaminated area.  相似文献   
65.
Transesophageal echocardiography (TEE) enhances our ability to see the patent ductus arteriosus in the dog. The improved visualization may potentially improve our ability to perform transcatheter coil embolization in patients that are more likely to have a successful outcome. This report uses still and video images to detail the specifics of coil embolization as performed with the assistance of TEE and compares the images with those of angiography, surgery and postmortem examination.  相似文献   
66.
Abstract

Survival and growth of juvenile octopi vary considerably. The objective of this research was to determine variations in weight, total lipids (TL), and total protein (TP) of newly hatched Octopus vulgaris paralarvae (0 days old) over the course of the spawning period. Newly hatched paralarvae dry weight from three females decreased throughout the spawning period. Similarly, newly hatched paralarvae TL percent decreased consistently (p < 0.05) in two of them and remained similar (p > 0.05) for the third female. Contrary, TP% did not vary regardless of the female or the time of hatching throughout paralarvae spawning. In conclusion, we believe that paralarvae used in O. vulgaris culture should be collected during the first 10 days of spawning, as they are larger and have higher lipid content; this increases the chances of a successful paralarvae culture, which is the major bottleneck in the culture of this species.  相似文献   
67.
Water, Air, & Soil Pollution - The Anllóns basin (NW Spain) has been included in the Natura 2000 Network and declared as Site of Community Importance. The main contamination problems of...  相似文献   
68.
The objective of this study was to isolate and identify yeast strains from broilers excreta and to evaluate in vitro their potential for probiotic use in animal production.Methods and resultsNine yeast strains were isolated and presumptively pre-identified by biochemical assays. These isolates were grouped in six different molecular profiles using PCR-fingerprinting technique. Each profile was identified by sequencing of the D1/D2 domains of the large subunit of the 26S rRNA gene. These yeasts were identified as: Trichosporon sp. (LV-2), Wickerhamomyces anomalus (LV-6), Pichia kudriavzevii (LV-8), Kodamaea ohmeri (LV-9) and Trichosporon asahii (LV-10). A pre-screening of the strains for probiotic use was based on their ability to agglutinate pathogenic micro-organisms. These yeast strains were characterized for specific growth rate, duplication time, their cell surface hydrophobicity, medium acidification, resistance to low pH (2.0, 2.5 and 3.0) and concentrations of bile salts (0.3% and 0.6%). The isolate of W. anomalus (LV-6) had the highest agglutinating and adherence capacity, a growth rate of 2.07 × 108 cfu/mL in 24 h at 30 °C, decreasing the medium pH from 6.5 to 5.23, a 25% hydrophobicity and an elevated capacity to grow under stress conditions.ConclusionsW. anomalus strain LV-6 showed the best characteristics for use as a probiotic candidate.Significance and impact of the Study:The data from this study helped in choosing a probiotic candidate from yeast to use in broiler production.  相似文献   
69.
70.
In spite of widespread application of flutamide in the endocrine therapies of young and adult patients, the side effects of this antiandrogen on spermatogenesis and germ‐cell morphology remain unclear. This study evaluates the short‐term androgen blockage effect induced by the administration of flutamide to the testes of pubertal (30‐day old) and adult (65‐ and 135‐day old) guinea pigs, with an emphasis on ultrastructural alterations of main cell types. The testes removed after 10 days of treatment with either a non‐steroidal antiandrogen, flutamide (10 mg/kg of body weight) or a pharmacological vehicle alone were processed for histological, quantitative and ultrastructural analysis. In pubertal animals, flutamide androgenic blockage induces spermatogonial differentiation and accelerates testes maturation, causing degeneration and detachment of primary spermatocytes and round spermatids, which are subsequently found in great quantities in the epididymis caput. In post‐pubertal and adult guinea pigs, in addition to causing germ‐cell degeneration, especially in primary spermatocytes, and leading to the premature detachment of spherical spermatids, the antiandrogen treatment increased the relative volume of Leydig cells. In addition, ultrastructural evaluation indicated that irrespective of age antiandrogen treatment causes an increase in frequency of organelles involved with steroid hormone synthesis in the Leydig cells and a dramatic accumulation of myelin figures in their cytoplasm and, to a larger degree, in Sertoli cells. In conclusion, the transient exposition of the guinea pigs to flutamide, at all postnatal ages causes some degenerative lesions including severe premature detachment of spermatids and accumulation of myelin bodies in Leydig and Sertoli cells, compromising, at least temporarily, the spermatogenesis.  相似文献   
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