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81.
A 4-year-old female French bulldog presented with a 6-month history of right-sided head tilt and acute onset ataxia. Magnetic resonance imaging (MRI) showed a large mass lesion at the cerebellomedullary pontine angle. The dog was able to stand and walk after beginning symptomatic therapy with prednisolone, acetazolamide and glycerin. Magnetic resonance imaging 10 months after the first examination indicated slight expansion of the tumor. The dog was able to walk with continuous symptomatic therapy for 15 months until death, although the head tilt persisted. On postmortem examination, the gross tumor was slightly larger than when seen on the second MRI scan and was histopathologically diagnosed as a choroid plexus papilloma.  相似文献   
82.
Historical profiles of trace element concentrations were reconstructed from two mangrove sediment cores collected within the Ba Lat Estuary (BLE), Red River, Vietnam. Chronologies of sediment cores were determined by the 210Pb method, which showed that each respective sediment core from the south and north entrances of BLE provided a record of sediment accumulation spanning approximately 100 and 60 years. The profiles of Pb, Zn, Cu, Cr, V, Co, Sb, and Sn concentrations markedly increased from the years of the 1920s–1950s, and leveled out from 1950s–1980s, and then gradually decreased from 1980s to present. The profiles of Cd and Ag concentrations increased from 1920s–1940s, and then decreased from 1940s to present. The profile of Mo concentrations progressively increased from 1920s–1980s, then decreased to present. The Mn concentrations failed to show a clear trend in both sediment cores. Results from contamination factors, Pearson’s correlation, and hierarchical cluster analysis suggest that the trace elements were likely attributed to discharge of untreated effluents from industry, domestic sewage, as well as non-point sources. Pollution Load Index (PLI) revealed levels higher than other mangrove sediment studies, and the long-term variations in PLI matched significant socioeconomic shifts and population growth in Vietnam. Geoaccumulation Index showed that mangrove sediments were moderately polluted by Pb and Ag, and from unpolluted to moderately polluted by Zn, Cu, and Sb. The concentrations of Pb, Zn, Cu, Cr, and Cd exceeded the threshold effect levels and effect range low concentrations of sediment quality guidelines, implying that the sediments may be occasionally associated with adverse biological effects to benthic organisms.  相似文献   
83.
ABSTRACT

In sub-Saharan Africa (SSA), rice production from smallholder farms is challenged because of a lack of fertilizer inputs and nutrient-poor soils. Therefore, improving nutrient efficiency is particularly important for increasing both fertilizer use and rice yield. This review discusses how to improve the return from fertilizer input in terms of agronomic N use efficiency (AEN), that is, the increase in grain yield per kg of applied N, for rice production in SSA. The AEN values we summarized here revealed large spatial variations even within small areas and a certain gap between researcher-led trials and smallholder-managed farms. Experimental results suggest AEN can be improved by addressing spatial variations in soil-related factors such as P, S, Zn, and Si deficiencies and Fe toxicity in both irrigated and rainfed production systems. In rainfed production systems, differences in small-scale topography are also important which affects AEN through dynamic changes in hydrology and variations in the contents of soil organic carbon and clay. Although empirical evidence is further needed regarding the relationship between soil properties and responses to fertilizer inputs, recent agricultural advances have generated opportunities for integrating these micro-topographical and soil-related variables into field-specific fertilizer management. These opportunities include UAV (unmanned aerial vehicle) technology to capture microtopography at low cost, database on soil nutrient characteristics at high resolution and more numbers of fertilizer blending facilities across SSA, and interactive decision support tools by use of smartphones on site. Small-dose nursery fertilization can be also alternative approach for improving AEN in adverse field conditions in SSA.

ABBREVIATIONS: AEN: agronomic nitrogen use efficiency; FISP: farm input subsidy program; VCR: value cost ratio; SOC: soil organic carbon; SSA: sub-Saharan Africa; UAV: unmanned aerial vehicle  相似文献   
84.
A 5-year-old female border collie presented with erythematous skin lesions at the axillae, groin, mucocutaneous junctions, and pinnae. Biopsy revealed lymphocytic interface dermatitis with hydropic degeneration of basal cells and keratinocyte apoptosis. Based on gross and histological features, diagnosis of erythema multiforme was made. The disease was resolved by treatment with azathioprine, prednisolone, and a hypoallergenic diet. Finally, the skin lesion was controlled without drug therapy but recurred easily every time commercial foods except the hypoallergenic diet were used, suggesting that food substances triggered this outbreak.  相似文献   
85.
The loss of developmental competence and the glutathione (GSH) content of maternally heat‐stressed mouse oocytes and zygotes were determined. In experiment 1, zygotes were collected from female mice that were heat‐stressed at 35°C for 10 h after hCG injection (oocyte maturation stage), or for 12 h on Day 1 of pregnancy (zygote stage), followed by in vitro culture. To minimize the effects of heat stress on the fertilization process, heat‐stressed oocytes that were fertilized in vitro were also included in this experiment. In experiment 2, heat‐stressed oocytes and zygotes were assayed for GSH content. The application of heat stress to the oocytes resulted in a significant decrease in the percentage of zygotes that developed to morulae or blastocysts, both for naturally fertilized oocytes (56.9% for heat‐stressed vs 85.4% for control) or in vitro‐fertilized oocytes (54.5%vs 73.6%). In the heat‐stressed zygotes, the disruption of embryonic development was more drastic (24.3%vs 90.3%), with the majority of zygotes being arrested at the two‐cell stage. In contrast, the GSH content decreased significantly in heat‐stressed zygotes, but not in heat‐stressed oocytes. These results demonstrate that the loss of developmental competence of early embryos is associated with a decrease in the GSH content of maternally heat‐stressed zygotes, but not of maternally heat‐stressed oocytes.  相似文献   
86.
The influence of nitrogen and sulfur compounds in rice grains on changes in flavor in stored sake was investigated using Japanese rice cultivars for sake making. Nitrogen content exhibited a significant positive correlation with sulfur content. Based on the molar ratio of nitrogen to sulfur in the rice grain, the sulfur compounds appeared to be derived from protein‐associated sulfur‐containing amino acids, as reported previously. The higher the protein content of the rice, the greater the amount of nitrogen and sulfur compounds found in both the digest of steamed rice grains and in the sake. Physicochemical changes were investigated in the stored sake to confirm the influence of total sulfur content. Polysulfides in the stored sake appeared to be higher when made from rice grains of high total sulfur content. Staling of stored sake was affected by levels of protein‐associated sulfur‐containing amino acids in the rice.  相似文献   
87.
When exposed to light, the Sekiguchi lesion (sl) rice mutant has an enhanced resistance to Magnaporthe grisea infection responsible for Sekiguchi lesion formation and tryptamine accumulation. Glyphosate [N-(phosphonomethyl) glycine] pretreatment suppressed Sekiguchi lesion formation and tryptamine accumulation in the sl mutant after M. grisea infection even under light. This inhibition by glyphosate was blocked by the supply of exogenous tryptophan, but not by exogenous phenylalanine. In glyphosate-pretreated leaves, 5-enol-pyruvyl-shikimate-3-phosphate synthase gene expression and tryptophan biosynthesis were significantly suppressed. During tryptophan starvation, catalase activity was maintained at a high level even under light, leading to the suppression of H2O2 generation and DNA fragmentation. These results show a strong relationship between the tryptophan and tryptamine pathways in the induction of light-enhanced resistance to M. grisea infection in the sl mutant.  相似文献   
88.
Seven of 92 lactating Holstein cows on a dairy farm developed urticaria with alopecia and decreased milk production, and three of the seven died over the course of 7 to 18 days. Pathologic examination of the three cows, including the two dead and one euthanized cow, revealed that the skin, liver, spleen, kidneys, heart, salivary glands, pancreas, adrenal glands, mammary glands, lymph nodes, and trigeminal ganglia had lymphocytic to lymphogranulomatous inflammation. Inflammation predominated by lymphocytic infiltration was prominent in the heart, pancreas, mammary glands, adrenal gland, and trigeminal ganglia. Severe granulomatous inflammation with multinucleated giant cells was present in the spleen and kidneys. These lesions and their distributions were most similar to those seen in suspected cases of citrus pulp toxicosis and hairy vetch toxicosis. The outbreak of this disease resolved with the elimination of Citrus pulp from the feed. Immunohistochemical detection of lymphocytes and macrophage markers confirmed dramatic hyperplasia of CD3-positive T lymphocytes in these lesions. This strongly suggested that a type 4 hypersensitivity reaction played a role in the development of the lesions.  相似文献   
89.
90.
Vitamin C content in the fruit of various cultivars of kiwifruit and other Actinidia species was estimated by determination of L-ascorbic acid and L-dehydroascorbic acid using ion-pair reversed-phase high-performance liquid chromatography. Fruit of A. deliciosa cv. Hayward, the most common commercially available cultivar, contained 65.5 mg/100 g fresh weight (FW) vitamin C. Vitamin C content in A. deliciosa fruit varied from 29 mg/100 g FW to 80 mg/100 g FW. In most cultivars of A. chinensis, vitamin C content in fruit was higher than that of Hayward. In particular, vitamin C content in cv. Sanuki Gold fruit reached more than 3-fold that of Hayward on a weight for weight basis. In A. argutafruit, there was wide variation in vitamin C content, with concentrations ranging from 37 to 185 mg/100 g FW. In cv. Gassan, Issai, and Mitsuko, vitamin C content of the fruit was much higher than that of Hayward. In A. arguta fruit, the ratio of L-ascorbic acid to total ascorbic acid tended to be higher than that of other species.  相似文献   
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