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81.
The effects of the addition of a slow pyrolysis biochar (produced from olive-tree prunings) to a vertisol were studied in a field experiment during one wheat (Triticum durum L.) growing season. The biochar addition did not significantly affect soil parameters such as pH, dissolved organic C and N, ammonium, nitrate or microbial biomass N. By contrast, biochar addition decreased soil compaction and increased the soil water-retention capacity and nutrient content (total N and the available contents of P, K, Mg, Cu and Zn). These favourable changes led to an increase in fine root proliferation (increasing specific root length and reducing root tissue density) and promoted crop development. As a result, the plants in biochar-treated plots showed higher relative growth and net assimilation rates, aboveground biomass and yield than those in control plots. Neither grain quality nor nutrient content were significantly affected by biochar addition. Our results suggest that the use of biochar as a soil amendment in agricultural soils can improve soil physical properties and increase fertility, favouring crop development under semiarid Mediterranean conditions.  相似文献   
82.

Objective

To determine if serum cardiac troponin I (cTnI) concentrations can distinguish cardiac from non-cardiac causes of respiratory distress (RD) in cats.

Animals, materials and methods

53 cats. cTnI concentrations were measured in 30 cats with non-cardiac respiratory distress (RD-NC) and compared to 23 cats with RD due to congestive heart failure (RD + CHF).

Results

The RD + CHF group had higher median cTnI concentration (0.94 ng/ml interquartile range IQR 0.54-4.00, range <0.20 - 90.14) than the RD-NC group (<0.2 ng/ml IQR < 0.2-0.33, range <0.20-41.1, p < 0.001). The area under the curve (AUC) was 0.842 (95% CI 0.728-0.955) for the receiver operator curve (ROC) analysis of the accuracy of cTnI concentrations to discriminate RD + CHF from RD-NC cats. A cut-off of ≥ 0.81 ng/ml discriminated RD + CHF from RD-NC cats with a sensitivity and specificity of 65.2% and 90.0% respectively. However considerable overlap in cTnI concentrations between the 2 groups was identified.

Conclusions

Serum cTnI concentrations were different in RD + CHF compared to RD-NC cats. However the overlap in cTnI concentrations between the 2 groups reduced the clinical efficacy of the assay which therefore should not be used as a stand-alone test but in combination with other diagnostics such as echocardiography and radiography.  相似文献   
83.
Conservation agriculture might have the potential to increase soil organic C content compared to conventional tillage based systems. The present study quantified soil organic carbon (SOC) and soil C derived from C3 (wheat) and C4 (maize) plant species using δ13C stable isotope. Soil with 16 y of continuous application of zero tillage (ZT) or conventional tillage (CT), monoculture (M) or rotation (R) of wheat and maize, and with (+r) and without retention (−r) in the field of crop residues were studied in the central highlands of Mexico. The highest SOC content was found in the 0-5 cm layer under ZTM and ZTR with residues retention. The soil cultivated with maize showed a higher SOC content in the 0-10 cm layer with residue retention than without residue. In the 10-20 cm layer, the highest SOC content was found in the CT treatment with residue retention. The SOC stock expressed as equivalent soil mass was greatest in the 0-20 cm layer of the ZTM (wheat and maize) and ZTR cultivated treatments with residue retention. After 16 y, the highest content of soil δ13C was found in ZTM + r and CTM + r treated soil cultivated with maize; −16.56‰ and −18.08‰ in the 0-5 cm layer, −18.41‰ and −18.02‰ in the 5-10 cm layer and −18.59‰ and −18.72‰ in the 10-20 cm layer respectively. All treatments had a higher percentages of C-C3 (derived from wheat residues or the earlier forest) than C-C4 (derived from maize residues). The highest percentages of C-C4, was found in ZTM + r and CTM + r treated soil cultivated with maize, i.e. 33.0% and 13.0% in 0-5 cm layer, 9.1% and 14.3% in the 5-10 cm layer and 5.0% and 6.8% in 10-20 cm layer, respectively. The gross SOC turnover was lower in soil with residue retention than without residues. It was found that the ZT system with residue retention and rotation with wheat is a practice with a potential to retain organic carbon in soil.  相似文献   
84.
Volatile compounds were isolated from four cultivars of bullock's heart fruit (Cenizo, Rojo, Verde, and De Ojo) by simultaneous steam distillation-solvent extraction. Compounds were identified by HRGC and capillary GC-MS. One hundred and eighty compounds were identified in the aroma extracts, of which alpha-pinene, beta-pinene, myrcene, limonene, terpinen-4-ol, and germacrene D were found to be the major constituents. Fruit from cv. De Ojo containing the highest concentration of total volatile and the highest major terpenoid content had the highest custard-like and overall fruity aroma intensity. The presence of many terpenic compounds is thought to contribute to the unique flavor of the bullock's heart fruit.  相似文献   
85.
An eight-week-old female Cavalier King Charles spaniel was presented with tachypnoea, pyrexia and distended jugular veins following bite injuries to the chest and abdomen. Pericardial effusion was suspected from clinical, electrocardiographic and radiographic findings, and confirmed by echocardiography. Pericardiocentesis was carried out and the purulent fluid aspirated yielded Pasteurella multocida on culture. After drainage, broad spectrum antibiotic therapy was instituted and the puppy went on to make an excellent clinical recovery. Despite this, some hyperechoic areas of myocardium were observed on echocardiography and occasional ventricular premature complexes were seen on electrocardiography. These were probably the result of an associated myocarditis.  相似文献   
86.
The capacity of carbohydrate and ketone bodies metabolism in brain and liver was evaluated in fed and food-deprived Atlantic salmon (Salmo salar) in a time period covering from 1 to 7 days (Experiment I), and in Atlantic salmon food deprived for 6 weeks, and food deprived for 4 weeks and refed for 2 weeks (Experiment II). The results obtained demonstrate for the first time in a teleost the existence of changes in brain metabolism due to food deprivation. Thus, decreased glucose levels in plasma are reflected in the brain by an increased mobilization of glycogen reserves, and by a decreased glycolytic capacity. Also, ketone bodies appear to increase their importance as a metabolic fuel from day 7 of food deprivation onwards. A possible increase in the gluconeogenic potential in brain simultaneously is not discarded. All these metabolic changes are reversed under refeeding conditions.  相似文献   
87.
Feline asthma syndrome (FAS) is a clinical condition characterised by recurrent bouts of coughing, wheezing and, or, dyspnoea. While the aetiology is unproven, the condition is believed to involve a type I immediate hypersensitivity reaction to inhaled allergens. In this paper the clinical data from 29 cats, where a diagnosis of FAS was made, are assessed retrospectively. The most common clinical presentation was recurrent bouts of coughing (n=26) and dyspnoea (n=21), Radiographic changes were noted in 24 cats, which included increased bronchial (n=5), interstitial (n=7) and mixed (n=12) (bronchial and interstitial) patterns. Right middle lung lobe collapse was noted in two cats. Abnormal bronchial cytology was present in 16 cats. A predominant eosinophilic sample was collected in only three cats. There were minimal changes in differential white cell counts, and mild eosinophilia was found in only five cats. Prednisolone alone was the most effective therapy, although avoidance of putative aeroallergens and antibacterial therapy was effective in some. On the basis of the data from these cases it would appear that the diagnosis of FAS depends largely on the clinical presentation and radiographic findings. The value of ancillary tests in the diagnosis of FAS appears to be limited.  相似文献   
88.
Anthelmintic efficacy of ivermectin against Mecistocirrus digitatus was evaluated in 10 naturally infected zebu calves. Group 1 (n = 5) was not treated, and group 2 (n = 5) was treated SC with 200 micrograms of ivermectin/kg of body weight. Calves were euthanatized 14 or 15 days after treatment. There was 100% overall reduction of M digitatus in treated calves, which was significant (P = 0.0079) compared with reduction in controls. Cooperia punctata, Haemonchus similis, and Trichostrongylus axei were found in controls. Efficacy against these parasites in treated calves was 100%.  相似文献   
89.
Cardiomyopathies are a heterogeneous group of myocardial disorders of mostly unknown etiology, and they occur commonly in cats. In some cats, they are well-tolerated and are associated with normal life expectancy, but in other cats they can result in congestive heart failure, arterial thromboembolism or sudden death. Cardiomyopathy classification in cats can be challenging, and in this consensus statement we outline a classification system based on cardiac structure and function (phenotype). We also introduce a staging system for cardiomyopathy that includes subdivision of cats with subclinical cardiomyopathy into those at low risk of life-threatening complications and those at higher risk. Based on the available literature, we offer recommendations for the approach to diagnosis and staging of cardiomyopathies, as well as for management at each stage.  相似文献   
90.
Human activities directly and indirectly influence the gene flow of wildlife populations, significantly affecting their population structure. On Bali, Indonesia, long-tailed macaque (Macaca fascicularis) populations are associated with relatively undisturbed forest remnants, providing resources for macaques through human worship practices. To evaluate the long-term impact of this anthropogenic landscape on gene flow in macaques, we measured the microsatellite heterozygosity and genetic distance of 15 populations across the island. We then used assignment tests to measure more contemporary movement between populations. We found significant population structure across the island and found that despite this significant structuring, contemporary macaque dispersal across the island is relatively high, with a number of first generation migrants detected. Moreover, we identified one population in the core of the island that acts as a magnet for migrants, receiving 50 % of the first generation migrants in this analysis. Finally, we used individual-level Bayesian clustering analysis combined with kriging techniques to measure fine-scale genetic structure and identify significant boundaries relative to the landscape. Significant genetic structure suggests that the existence of forested temple sites and long-term co-existence with humans may have contributed to relative isolation between populations, even though macaques are known for their high dispersal abilities. However, more recent changes in land use practices in Bali, such as reallocation of lands for tourism, are influencing the patterns of dispersal and increasing the movement of individuals between novel sites, shifting the population structure of the macaques and potentially reducing island-wide genetic diversity.  相似文献   
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