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131.
Reasons for performing study: Sarcoids are nonmetastasising, yet locally aggressive skin tumours that constitute the most frequent neoplasm in equids. Infection by bovine papillomaviruses types 1 and 2 (BPV‐1, BPV‐2) has been recognised as major causative factor in sarcoid pathogenesis, but a possible correlation of intralesional virus load with disease severity has not been established thus far. Hypothesis: Given the pathogenic role of BPV‐1 and BPV‐2 in sarcoid disease, we suggest that intralesional viral DNA concentration may reflect the degree of affection. Methods: Severity of disease was addressed by recording the tumour growth kinetics, lesion number and tumour type for 37 sarcoid‐bearing horses and one donkey. Viral load was estimated via quantitative real‐time PCR (qPCR) of the E2, E5, L1 and L2 genes from the BPV‐1/‐2 genome for one randomly selected lesion per horse and correlated with disease severity. Results: Quantitative PCR against E2 identified viral DNA concentrations ranging from 0–556 copies/tumour cell. Of 16 horses affected by quiescent, slowly growing single tumours or multiple mild‐type lesions, 15 showed a viral load up to 1.4 copies per cell. In stark contrast, all equids (22/22) bearing rapidly growing and/or multiple aggressive sarcoids had a viral load between 3 and 569 copies per cell. Consistent results were obtained with qPCR against E5, L1 and L2. Conclusions: While tumours of the same clinical type carried variable virus load, confirming that viral titre does not determine clinical appearance, we identified a highly significant correlation between intralesional viral load and disease severity. Potential relevance: The rapid determination of BPV viral load will give a reliable marker for disease severity and may also be considered when establishing a therapeutic strategy.  相似文献   
132.
Objective  To describe the technique for implantation of a novel keratoprosthesis (KP) prototype and evaluate its application for the treatment of corneal blindness in dogs.
Animals studied  Seven dogs, all of them being clinically blind before surgery as a result of severe corneal endothelial disease (5/7) or chronic superficial keratitis (2/7) that were unresponsive to prior therapy.
Procedures  A silicone KP was implanted unilaterally, just anterior to Descemet's membrane, after creating a stromal pocket by deep stromal lamellar dissection.
Results  Implantation of the KP was accomplished without complication in six of seven operated dogs. In the remaining case, an intra-operative complication (perforation of Descemet's membrane) was associated with extrusion of the KP 8 weeks postoperatively. All operated eyes regained limited vision after surgery. Three to six months after implantation purulent keratitis occurred in all five eyes with endothelial disease, necessitating surgical removal of the KP 6 months postoperatively in 5/7 eyes.
Conclusions  This KP prototype shows promise as a treatment for certain blinding corneal diseases. However, changes in the design of this KP, allowing improved stromal integration, will be necessary before its clinical application can be approved.  相似文献   
133.
The aims of this study were to examine fin erosion caused by social interactions between Atlantic cod (Gadus morhua) juveniles, and to evaluate the repeatability of recorded fin length using digital image analysis (DIA). Fin length of 2100 juvenile Atlantic cod was analysed using DIA, during a 6 weeks experiment. The lengths of the three dorsal fins and the caudal fin were measured by three different assessors (M, K, B) three times during the experiment. Repeatability was based on a sub set of data from 42 randomly chosen fish. Assessor M measured the length of the fins of the 42 fish three times (M1, M2, M3). M1 and M2 were done on the same day, while M3 was conducted 2 weeks later. Assessor K measured two times with a 2‐year interval, and assessor B measured the fin length only once. The correlations between replicated measurements within assessor were highest for assessor M measured on the same day indicating an effect of memory. Repeatability of fin length ranged from 0.57 to 0.73 for the four fins. Social interaction with respect to fin erosion was studied using data on the four fins from all 2100 fish. ‘Relative fin length’ (fin length/total body length × 100) was calculated to assess fin erosion. Results indicated that all four fins were eroded due to social interactions, but the caudal fin was most severely eroded. In conclusion, DIA can be used to measured fin length but the method could be improved by using chromatic pictures.  相似文献   
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135.
Summary

When strawberries (Fragaria ananassa Duch.) are produced in a greenhouse, usually two crops a year are obtained; in the fall and in the spring. To increase productivity, new cultivation techniques are needed. The aim of this study was to examine the effect of daylength treatments on the performance of strawberry plants to improve plant production protocols. The possibility of obtaining two successive crops during forcing was explored by exposing plants of cultivar Korona to two successive short day (SD) treatments followed by cold storage. The following daylength treatments were studied: 3 wk SD + 2 wk long day (LD) + 3 wk SD (3SD2LD3SD), 3 wk SD + 4 wk LD + 3 wk SD (3SD4LD3SD), and 10 wk SD (10SD). In addition, crown branching was studied in plants subjected to SD treatments. Two successive SD treatments enabled two successive flowering and cropping periods during greenhouse forcing after eight weeks of cold storage.The first SD treatment caused crown branching and induced flowering in the apical meristem of the main-crown and in the oldest axillary meristem(s), whereas younger axillary meristems were induced during the second SD treatment. Marketable yield and the number of inflorescences were comparable in 3SD4LD3SD and 10SD, but considerably lower in 3SD2LD3SD. However, this study demonstrated the high cropping potential of artificially SD treated plants, which makes them a potential alternative for greenhouse strawberry cultivation. Multi-crowned plants of ‘Korona’ can be produced by subjecting young plants to a three week SD treatment, and crown branches can be induced to flowering by a new SD treatment resulting in a very high cropping potential. Induced plants can be stored at –1°C for later forcing.  相似文献   
136.
In this study, the concentrations of 15 perfluorinated compounds (PFCs) were analyzed in 30 water samples collected in Catalonia (Spain) at three stages of the drinking water treatment process in several water purification plants. In addition, the concentrations of 13 PFCs were determined in samples of fish and shellfish collected from coastal areas of Catalonia. The intake of PFCs through both pathways, drinking water intake and fish and shellfish consumption, was also estimated. In water samples, the highest mean concentrations corresponded to perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) (1.81 and 2.40 ng/L, respectively), whereas perfluorodecanosulfonate (PFDS) and perfluorotetradecanoic acid (PFTDA) were under their respective limits of detection in all analyzed samples. The results show that although the current treatment processes caused slight reductions in PFC concentrations, these processes did not mean significant changes in the amounts of PFCs already contained in the raw water. Among the analyzed PFCs in fish and shellfish, only seven compounds could be detected in at least one composite sample. PFOS showed the highest mean concentration (2.70 ng/g fw), being detected in all species with the exception of mussels. With regard to PFOA (mean, 0.074 ng/g fw), the highest concentrations were detected in prawn and hake (0.098 and 0.091 ng/g fw, respectively). The current exposure to PFCs through consumption of fish and shellfish indicates that it should not be of concern for the consumers. The amounts ingested are well below the recommended tolerable daily intakes, at least for those PFCs for which information is available.  相似文献   
137.
Greywater is a potential resource of water that can be improved to meet the quality needed for irrigation. This study evaluated the performance of bark, activated charcoal, polyurethane foam and sand filters in removing biochemical oxygen demand (BOD5), surfactants, phosphorus, nitrogen and microbial indicators from greywater during start-up and steady state. In column experiments, 0.6?m high filters (diameter 20?cm) were fed for 113?days with artificial greywater at a hydraulic loading rate of 0.032?m3?m?2?day?1 and an organic loading rate of 0.014?kg BOD5 m?2?day?1. Bark and activated charcoal efficiently reduced the concentrations of organics (BOD5), surfactants (methylene blue active substances??MBAS), total phosphorus (Tot-P) and total thermotolerant coliform numbers, while sand and foam were less efficient. Bark, activated charcoal, foam and sand reduced influent BOD5 by 98, 97, 37 and 75?%; MBAS by >99, >99, 73 and 96?%; Tot-P by 97, 91, 36 and 78?%; and total nitrogen by 19, 98, 13 and 5?%, respectively. BOD5 and MBAS were efficiently reduced directly from start-up by bark and activated charcoal, while foam needed 30?days to achieve about 50?% reduction in BOD5. Bark was the most efficient filter in reducing thermotolerant faecal coliforms (2.4 log10), while foam achieved the lowest reduction (0.5 log10). Overall, bark and activated charcoal filters appeared to be the most suitable filters for improving greywater quality to reach irrigation quality in terms of organic matter reduction. Performance of these filters under higher and fluctuating loadings and the long-term sustainability of the filter materials need further investigation.  相似文献   
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139.
The aim of this study was to determine the changes in diameter of corpus luteum (CL), maternal progesterone (P) concentration, lipid peroxidation and non‐enzymatic antioxidant levels along with enzymatic antioxidant activities in pregnant ewes bearing single and twin foetuses. The ewes were selected from healthy animals that were brought to the abattoir for slaughtering. The ewes were divided into three groups: Group 1 (non‐pregnant, non‐oestrous, n = 30), Group 2 (pregnant bearing a single foetus, n = 30) and Group 3 (pregnant bearing twin foetuses, n = 12) after they were slaughtered. Pregnant ewes were in the first half of the pregnancy. The diameter of CL and P concentration of pregnant ewes bearing a single foetus or twin foetuses were found higher than that found in non‐pregnant ewes. Similarly, the P concentration of pregnant ewes bearing twin foetuses was higher than that found in pregnant ewes bearing a single foetus. Malondialdehyde (MDA) level in pregnant ewes bearing twin foetuses was higher than that found in both non‐pregnant and pregnant ewes bearing a single foetus. The serum glutathione (GSH) level and glutathione‐peroxidase (GSH‐Px) activity of pregnant ewes bearing twin foetuses were found lower than that found in non‐pregnant ewes. Additionally, the GSH‐Px activity of pregnant ewes bearing twin foetuses was found lower than that found in pregnant ewes bearing a single foetus. No significant difference was found between pregnant ewes bearing female and male foetus with respect to diameter of CL, P concentration and oxidative stress parameters. There were significant positive correlations between foetal number (0, 1, 2) and diameter of CL, P concentration, MDA level, and between P concentration and diameter of CL, MDA level. However, significant negative correlations were found between foetal number (0, 1, 2) and GSH level, GSH‐Px activity, and between P concentration and GSH‐Px activity. In conclusion, the diameter of CL enlarges, P production increases and oxidant/antioxidant balance impairs because of the gestation stress in ewes during pregnancy.  相似文献   
140.
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