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111.
A 12-year-old female dog with a 3-month history of poor response to diabetes treatment had an acute worsening of symptoms, including weakness and blindness. The dog had elevated blood glucose, alkaline phosphatase and urea concentration, hyposthenuria, glycosuria, hematuria, and pyuria. Escherichia coli was isolated from the urine. Radiographs and ultrasound examination showed that the dog had unilateral emphysematous pyelitis and concurrent cystitis associated with vesicoureteral reflux.  相似文献   
112.
The pest Halyomorpha halys is a recent example of severe worldwide biological invasion. In Italy, after the first detection in 2012, it has rapidly spread and economic damage has already been reported in commercial fruit orchards, eliciting enormous concern for Italian agricultural production. As a long-term solution, biological control investigations are focusing on the potential of natural antagonists, such as generalist predators, in the invaded areas. Due to their biology, ecology and behavior, ants represent one such generalist predator potentially suitable for inflicting mortality on H. halys. In this research, Crematogaster scutellaris was used as a study model. Specifically, the effect of ant predatory behavior on the survival of all H. halys pre-imaginal stages was tested in the laboratory environment. The results suggest that C. scutellaris has a significant predatory impact on all H. halys pre-imaginal stages except for eggs. The reduction of survivorship is between 95 and 85% for instars 1 and 2 and between 38 and 52% for instars 3, 4 and 5. The different levels of predation success suggest that these ants could act as useful generalist predators when associated with other antagonists and/or other control strategies. Although further field investigations are needed, the potential of ants as biocontrol agents of invasive species in agroecosystems deserves consideration in integrated pest management programs.  相似文献   
113.
The evaluation of the bioaccessibility of almond nutrients is incomplete. However, it may have implications for the prevention and management of obesity and cardiovascular disease. This study quantified the release of lipid, protein, and vitamin E from almonds during digestion and determined the role played by cell walls in the bioaccessibility of intracellular nutrients. Natural almonds (NA), blanched almonds (BA), finely ground almonds (FG), and defatted finely ground almonds (DG) were digested in vitro under simulated gastric and gastric followed by duodenal conditions. FG were the most digestible with 39, 45, and 44% of lipid, vitamin E, and protein released after duodenal digestion, respectively. Consistent with longer residence time in the gut, preliminary in vivo studies showed higher percentages of nutrient release, and microscopic examination of digested almond tissue demonstrated cell wall swelling. Bioaccessibility is improved by increased residence time in the gut and is regulated by almond cell walls.  相似文献   
114.
Zeolitites (ZTs) are rocks containing more than 50% of zeolite minerals and are known to be a suitable material for agricultural purposes by improving soil physicochemical properties and nitrogen (N) use efficiency. However, little is known about their effects on soil microbial biomass. This study aimed to evaluate short-term effects of different chabazite-rich ZT (CHAZT) amendments on soil microbial biomass and activity. A silty-clay agricultural soil was amended in three different ways, including the addition of natural (5% and 15%) and NH_4~+-enriched (10%) CHAZT. Soil dissolved organic carbon (C), total dissolved N, NH_4~+, NO_3~-, NO_2~-, microbial biomass C and N, and ergosterol were measured periodically over 16 d in a laboratory incubation. To verify the microbial immobilization of the N derived from NH_4~+-enriched CHAZT, a high15N source was used for enriching the mineral to measure the microbial biomass δ15N signature. An increase in the ergosterol content was observed in the soil amended with 5% natural CHAZT. However, no similar result was observed in the soil amended with 15% natural CHAZT, suggesting that the fungal biomass was favored at a lower CHAZT application rate. In the soil amended with NH+ 4-enriched CHAZT, microbial biomass N was related to NO_3~-production over time and inversely related to NH_4~+, suggesting high nitrification process. Isotopic measurements on microbial biomass confirmed immediate assimilation of N derived from NH_4~+-enriched CHAZT. These results suggested that the NH_4~+-enriched CHAZT used in this study supplied an immediately available N pool to the microbial biomass.  相似文献   
115.
The nitrogen content of humic and fulvic acid fractions recovered in parallel with sodium hydroxide and a mixture of sodium hydroxide and sodium pyrophosphate from a volcanic soil under pine was determined. Despite minor differences for some horizons, the values found by the two methods were similar. Furthermore, the ratio between the N contents in the humic and fulvic acid fractions (Nh : Nf) was independent of the nature of the extractant. This fact and the facility of the determination suggest investigating if the Nh: Nf ratio can be used as indicator for the quality of soil organic matter.  相似文献   
116.
Low‐molecular‐weight organic acids (LMWOA's) play an important role in soil genesis and plant physiology. Oxalic acid is one of the more common and abundant LMWOA's in forest soils, where it accumulates especially as salts of Ca. In two soils under silver fir (Abies alba Mill.) from Tuscany, Italy, we measured the oxalate concentration of the entire profile. Oxalate was present up to two metres depth, but accumulates preferentially in the upper horizons. We determined also the bulk density of the fine earth, and organic carbon and available phosphorus. In one of the two soils, the oxalate concentration along the profile was regressed negatively with depth and bulk density, and positively with organic C and available P.  相似文献   
117.
Eight healthy dogs undergoing elective ovariohysterectomy were anesthetized with a standard protocol and received a low-dose medetomidine constant rate infusion during surgery. Cardiorespiratory parameters, including non-invasive cardiac output, were measured at various times. This protocol resulted in acceptable and stable cardiovascular performance, allowed low isoflurane concentrations, and provided smooth recoveries.  相似文献   
118.
In tropical Africa and Asia, two species of the predatory ant genus, Oecophylla, play a crucial role in protecting tree crops against pests and enhancing the quality of fruits and nuts. As predatory effectiveness is influenced by the presence of other dominant ant species, understanding the ecological factors at work in agroecosystems lies at the basis of conservation biological control. Over three and a half years, the effect of ground vegetation management on the beneficial tree-nesting ant Oecophylla longinoda (Latreille) and its competitor, the ground-nesting ant, Pheidole megacephala (Fabricius), was studied in a citrus orchard in Tanzania. When ground vegetation was present, P. megacephala tolerated O. longinoda and to some extent cohabited with this ant in citrus trees. However, after clean cultivation, P. megacephala displaced O. longinoda from tree crowns and became the sole occupant of the majority of trees. Displacement could be reversed by reversing the weed management regime, but this took time. Two years after the establishment of ground vegetation about half of the trees were colonized by Oecophylla only. Maintaining ground vegetation in tree crop plantations benefits the establishment and abundance of Oecophylla over Pheidole and is recommended in order to improve the efficiency of biological control of tree pests. The use of Amdro ant bait (hydramethylnon) to control P. megacephala is discussed. Boosting agroecological innovations, such as the one described in this paper, could benefit smallholder producers.  相似文献   
119.
A defining factor for the commercial value of durum wheat pasta is its amber colour, which depends on the semolina yellow pigment concentration and on the oxidative enzymatic activity. Among carotenoids controlling yellow colour, the presence of β-carotene is also important as precursors of vitamin A. The aim of the present study was to detect quantitative trait loci (QTL) for yellow pigment concentration, yellow index and individual carotenoid compounds (lutein, zeaxanthin, β-cryptoxanthin, α-carotene and β-carotene) in a durum segregant population. Total carotenoid concentration amounted to 37% of the yellow pigments, indicating unknown colour-producing compounds in the durum extracts. Lutein was the most abundant carotenoid, followed by zeaxanthin, α-carotene and β-carotene, while β-cryptoxanthin was a minor component. Phytoene synthase marker Psy-A1, 150 SSR and EST-SSR markers, and 345 DArT® markers, were used to construct the linkage map for subsequent QTL analysis. Clusters of QTL for total and/or one or more carotenoid compounds were detected on the same chromosome regions (2A, 3B, 5A and 7A) where QTL for yellow pigment concentration and yellow index were identified. The molecular markers associated to major QTL would be useful for marker-assisted selection programs to facilitate high carotenoid concentration with high nutritional carotenoid compounds in wheat grain.  相似文献   
120.
Many studies have demonstrated the role of polyphenol oxidase (PPO; E.C. 1.14.18.1) in darkening of wheat products. Even slight browning of pasta is a major hindrance to consumer acceptance. The aim of this research was to evaluate the variability of PPO activity, browning level, and protein content in a collection of more than 100 genotypes of tetraploid wheat, including cultivars and landraces. A molecular approach was followed to evaluate the efficiency of marker PPO18, discovered and used in common wheat, in detecting tetraploid wheat genotypes with low browning level. The data showed a significant genotype influence on the activity of the PPO enzyme, which was correlated with brown index of whole meal and dough, and with protein content. On the whole, the cultivars showed lower PPO activity, brown index, and protein content than landraces, but wide variability was present. Marker PPO18 detected four different alleles for Ppo-A1. The allele Ppo-A1f identified genotypes with high PPO activity and brown index, while the Ppo-A1b and null alleles were associated with the opposite characteristics. Hence, this marker can be used to select new tetraploid wheat cultivars with low browning level.  相似文献   
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