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31.
A 6‐day‐old foal was evaluated for depression and inappetence. After initial stabilization, the filly developed a hypochloremic metabolic alkalosis and persistent hypercreatinemia. Abdominal ultrasound revealed fluid accumulation around the left kidney and a well‐defined rounded fluid filled structure dorsal to the urinary bladder. Computed tomography revealed a partial tear of the left ureter with distension of the retroperitoneal membrane. Exploratory celiotomy was performed to allow left kidney nephrectomy. At 6 months follow‐up, the filly was growing normally without complications. Ultrasound and CT imaging in this case provided an accurate diagnosis and a presurgical aid to select the appropriate therapeutic approach.  相似文献   
32.
Since 2006, the members of the molecular epidemiological working group of the European "EPIZONE" network of excellence have been generating sequence data on avian influenza and avian paramyxoviruses from both European and African sources in an attempt to more fully understand the circulation and impact of these viruses. This review presents a timely update on the epidemiological situation of these viruses based on sequence data generated during the lifetime of this project in addition to data produced by other groups during the same period. Based on this information and putting it all into a European context, recommendations for continued surveillance of these important viruses within Europe are presented.  相似文献   
33.
Sporotrichosis is a mycosis caused by Sporothrix schenckii. The most affected animal is the cat; it has played an important role in the zoonotic transmission of this disease, especially in Rio de Janeiro, Brazil, since 1998. In order to evaluate the treatment of feline sporotrichosis with potassium iodide, an observational cohort was conducted in 48 cats with sporotrichosis at Instituto de Pesquisa Clínica Evandro Chagas, Fiocruz. All cats received potassium iodide capsules, 2.5 mg/kg to 20 mg/kg q24h. The cure rate was 47.9%, treatment failure was 37.5%, treatment abandonment was 10.4% and death was 4.2%. Clinical adverse effects were observed in 52.1% of the cases. Thirteen cats had a mild increase in hepatic transaminase levels during the treatment, six of them presented clinical signs suggestive of hepatotoxicity. Compared to previous studies with itraconazole and iodide in saturated solution, potassium iodide capsules are an alternative for feline sporotrichosis treatment.  相似文献   
34.
Diagnosing high intracranial pressure by clinical and diagnostic imaging is particularly challenging for chronic or slow‐growing lesions. The aim of this prospective case‐control study is to determine whether the neuroscore and brain magnetic resonance imaging (MRI) are related to the direct measurement of intracranial pressure in sheep affected by intracranial slow‐growing lesions due to chronic cerebral coenurosis (Coenurus cerebralis). Seventeen affected and 10 control sheep were included. All animals underwent a neurological examination, MRI of the brain, and direct measurement of intracranial pressure. The severity of clinical signs and MRI findings were scored. Data were statistically analyzed. The invasive intracranial pressure value was higher in affected animals. A severely altered neuroscore is related to an increased intracranial pressure beyond the normal threshold (< 0.05). The volume of the calvarium was larger in affected animals than in control animals (P = 0.0001) and was positively influenced by the presence and volume of the parasitic cyst (r = 0.7881, P < 0.01). Several degrees of deviation and deformation of both the ventricular system and brain parenchyma were detected by MRI. Subjective MRI findings were not associated with intracranial hypertension. In conclusion, this study shows that in sheep affected by slow‐growing lesions, severe alterations in the neuroscore and the results of objective MRI are related to an increased intracranial pressure beyond the normal threshold.  相似文献   
35.
Jellyfish are commonly considered a nuisance for their negative effects on human activities (e.g., fisheries, power plants and tourism) and human health. However, jellyfish provide several benefits to humans and are commonly eaten in eastern countries. Additionally, recent studies have suggested that jellyfish may become a source of high-value molecules. In this study, we tested the effects of the methanolic extracts and enriched fractions, obtained by solid-phase extraction fractionation, from the scyphomedusae Pelagia noctiluca, Rhizostoma pulmo, Cotylorhiza tuberculata and the cubomedusa Caryddea marsupialis on different human cancer cell lines in order to evaluate a potential antiproliferative activity. Our results indicated that fraction C from Caryddea marsupialis-(CM) and C. tuberculata oral arms (CTOA) were the most active to reduce cell viability in a dose-dependent manner. LC/MS based dereplication analyses highlighted that both bioactive fractions contained mainly fatty acids and derivatives, with CM additionally containing small peptides (0.7–0.8 kDa), which might contribute to its higher biological activity. The mechanism of action behind the most active fraction was investigated using PCR arrays. Results showed that the fraction C of CM can reduce the expression of genes involved in apoptosis inhibition in melanoma-treated cells, which makes jellyfish a potential new source of antiproliferative drugs to be exploited in the future.  相似文献   
36.
Top dieback of Norway spruce (Picea abies), triggered by drought in 2004–2006, has been observed in Southeast Norway and trees died within four years after appearance of the first symptoms. The aim of our study was to use sap flux measurements as a diagnostic method for assessment of tree vitality. We used the heat field deformation method to monitor the sap flux density (SFD) in four pairs of healthy and declining trees in situ. To provide retrospective information on hydraulic performance of the trees we took samples for wood anatomical analysis. After felling the trees we used the modified differential translucence method (MDT) as a proxy for the SFD measurements. Healthy trees had three times higher SFD values as declining trees. In some healthy trees we detected decreasing SFD with time. The MDT method agreed with the SFD measurements. In conclusion, we detected sap flux dysfunction in declining trees and showed that the SFD reduction may occur during a short period, prior to occurrence of any visual symptoms. We suggest incorporating the SFD measurements into the repertoire of diagnostic tools in forest pathology.  相似文献   
37.
Common property rights have a long tradition in the Italian Alps, dating back to the Middle Ages, when alpine village communities managed common forests. On these properties, in accordance with rules aimed at regulating the collective use of resources, shareholders have the right of common use of the land. As many mountainous areas still rely on firewood for the heating of homes, the right to gather firewood from common forests is the most important common property right. In the last few decades, renewable bio-energy production based on forest woody biomass has undergone significant development. In Italy, in communities where the right to gather wood still has economic, social, and cultural relevance, decision makers and community members have a different vision about the use of firewood. This paper focuses on this issue by presenting a case study located in the Italian Eastern Alps, characterised by a historical tradition of common property management. In order to define the optimal strategy to manage the common forests, taking into consideration the local community’s needs, a semi-structured questionnaire was submitted to the administrators of the common forests and to the shareholders. Different scenarios of wood use were developed to support managers and decision makers in identifying on-going trends in firewood demand. The results show that the economic scenario for the development of the bio-energy supply chain cannot be reconciled with the historical tradition and social needs.  相似文献   
38.
The functionally critical role of mycorrhizal fungi in forest ecosystems, and the imminent threat of climate change that may act to alter mycorrhizal functional biodiversity, means there is an urgent need for a regional to continental-scale assessment of mycorrhizal distributions. Until recently, it had not been possible to cost-effectively assess mycorrhizas precisely and accurately. A large-scale survey of ICP Forests plots would be only the first stage in answering many of the questions outlined above, but it is essential if future studies are going to address these questions with hypothesis-driven research in a cohesive manner, rather than remain independent for lack of a unified approach. The chance to utilise the vast network of biomonitoring plots at this time is a remarkable opportunity because it minimises the logistics and costs associated with achieving such an enormous effort and provides a rare stable — past and future — ground for forest ecosystem scientific investigation. In the face of rapid global change, we finally have an opportunity to accurately integrate mycorrhizal distribution data with long-term environmental monitoring, providing a basic understanding of functionally crucial organisms, and at the same time creating an invaluable resource for future research.  相似文献   
39.
Flavobacterium psychrophilum is the causative agent of bacterial cold-water disease and rainbow trout syndrome in freshwater salmonid fish worldwide, generating injuries and high mortality rates. Despite several studies on this bacterium, the infection mechanism remains unknown due to limitations in the employed animal models. In this work, we propose using zebrafish (Danio rerio) as a model for studying bacterial pathogenicity. To substantiate this proposal, zebrafish infection by F. psychrophilum strain JIP 02/86 was characterized. Zebrafish larvae were infected using the bath method, and morphological changes and innate immune system activation were monitored using transgenic fish. Salmonid-like infection phenotypes were observed in 4.74% of treated larvae, as manifested by fin, muscle and caudal peduncle damage. Symptomatic and dead larvae accounted for 1.35% of all challenged larvae. Interestingly, infected larvae with no infection phenotypes showed stronger innate immune system activation than specimens with phenotypes. A failure of function assay for myeloid factor pu.1 resulted in more infected larvae (up to 43.5%), suggesting that low infection rates by F. psychrophilum would be due to the protective actions of the innate immune system against this bacterium in zebrafish larvae. Our results support the use of zebrafish as an infection model for studying F. psychrophilum. Furthermore, the percentage of infected fish can be modulated by disturbing, to varying extents, the differentiation of myeloid cells. Using this evidence as a starting point, different aspects of the infection mechanism of F. psychrophilum could be studied in vivo.  相似文献   
40.
Trees must respond to many environmental factors during their development, and light is one of the main stimuli regulating tree growth. Thinning of forest stands by selective tree removal is a common tool in forest management that increases light intensity. However, morphological and anatomical adaptations of individual shoots to the new environmental conditions created by thinning are still poorly understood. In this study, we evaluated shoot morphology (shoot length, needle number, projected leaf area) and anatomy (tracheid lumen area, tracheid number, tracheid dimensions, xylem area, potential hydraulic conductivity) in three Norway spruce (Picea abies/L./Karst.) families exposed to different thinning regimes. We compared shoot characteristics of upper-canopy (i.e. sun-exposed) and lower-canopy (i.e. shaded) current-year shoots in a control plot and a plot thinned to 50 % stand density the previous year. One tree per family was chosen in each treatment, and five shoots were taken per canopy position. We found that upper-canopy shoots in both plots had higher values than lower-canopy shoots for all studied parameters, except lumen roundness and tracheid frequency (i.e. tracheid number per xylem area). Thinning had little effect on shoot morphology and anatomy 1 year after thinning, except for small but significant changes in tracheid dimensions. Needles were more sensitive to altered light conditions, as projected leaf area of shoot, needle number and leaf hydraulic conductivity changed after thinning. Differences between upper- and lower-canopy shoots did not seem to be influenced by thinning and were almost the same in both plots. Our results suggest that lower-canopy shoots require several years to modify their morphology and anatomy to new light conditions following thinning. The slow light adaptation of the lower canopy may be of practical importance in forest management: thinned stands may be predisposed to drought stress because newly exposed shoots experience increased illumination and transpiration after thinning.  相似文献   
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