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91.
Jean-Yves Cornu David Huguenot Karine Jezequel Thierry Lebeau 《Journal of Soils and Sediments》2013,13(1):220-229
Purpose
Sugar beet pulp (SBP) has been shown to be a promising low-cost sorbent for the removal of metals from contaminated waters. The objective of this study was to investigate the impact of SBP addition to horizontal-flow gravel filters in increasing the copper (Cu) retention ability of stormwater basins.Material and methods
Small-scale gravel filters filled with 6 kg of a sand–sediment mix (SS) were used to experimentally treat Cu-contaminated water under conditions that represented an intense storm event. Sugar beet pulp efficiency was assessed by adding 100 g of raw SBP. Two ways of applying SBP were tested: (1) mixed with SS into the gravel filter or (2) packed at the outlet in a PVC column. Eluates were characterized by their volume, pH, Cu and dissolved organic carbon (DOC) concentrations.Results and discussion
When placed at the outlet, SBP fixed 73 % of the Cu remaining in solution and increased the overall retention capacity of the gravel filter to 99.4 %. Conversely, when SBP was mixed with SS, the outflowing water carried higher concentrations of Cu and DOC. Complementary batch experiments underlined the crucial role of DOC in the decline of Cu sorption ability observed when SS and SBP were mixed. Geochemical calculations suggested that DOC (assumed to be pectins) promotes the mobilisation of Cu from SS by complexing it in porewater.Conclusions
Accompanied with careful guidance, SBP has the potential of removing dissolved Cu from contaminated water in gravel filters. Protocols for SBP preparation and conditions of use should be established so as to promote its sorption efficiency and decrease its release of Cu-complexing compounds like pectins. 相似文献92.
G. Koptopoulos M. Papanastasopoulou O. Papadopoulos H. Ludwig 《Comparative immunology, microbiology and infectious diseases》1988,11(3-4):199-205
Previous preliminary studies had shown that caprine herpesvirus (BHV-6) infections exist in many countries where goats play an economical role. The extensive serum survey made in Greece reveals that the virus must be widespread because more than 50% of the goats have antibodies. The bucks were found to have a higher evidence of infections than the female goats. The kids possessing maternal antibodies became seronegative at the age of 4 months and new antibodies appeared at the age of 7–8 months. Observations in 2 closed goat herds showed that the virus does not spread during the mating and lactating period. Neutralization titres increased or new infections in seronegative animals occurred after the summer when breeding took place. The virus is present in a latent state and recurrent infections are assumed to occur. In spite of that all our efforts to isolate the virus were unsuccessful, even after experimental immunosuppression. 相似文献
93.
Lúcia D.M. Silva Karine Onclin John P. Verstegen 《Veterinary radiology & ultrasound》1996,37(4):313-320
To identify the time characteristics of ovulation, 5 bitches were evaluated during heat by ultrasonography, laparoscopy and hormonal assay. Blood collections for progesterone and oestradiol 17-β assys and ultrasonography were performed every day and laparoscopy every other day. At ultrasonography, ovaries appeared as anechoic structures about 5 days before the estimated LH peak and gradually increased in size. The greatest changes were observed between days 2 and 4 post-LH peak: echogenicity varied greatly from one animal to another and from one day to the following going from totally anechoic to mixed hypo and hyperechogenicity. Then from day 6, ovaries always appeared as hypoechoic structures assimilated to corpora lutea. At laproscopy, small follicies were seen as early as day 10 before the LH peak. Their size slowly increased to become large protubering follicies around the day of LH peak (day 0). At day 1, corpra luta were observed for the first time and were present in all animals by day 5. During that period preceeding day 5, some ovaries had both corpora lutea and follicies clearly visible on their surface. In one animal, haemorrhagic foci were observed at day 3. Neither ultrasonography, nor laparoscopy allowed precise determination of the time of ovulation. Indeed, follicle collapses was never observed, but changes in echogenicity and in the appearance of the ovaries observed by laparoscopy, suggested that ovulation occurred between days 2 and 4 when progestrone concentrations were 12.6 ± 6.2 and 32.1 ± 10.9 nmol/L, respectively. 相似文献
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The pathogenesis of paraesophageal empyema in dogs and constancy of radiographic and computed tomography signs are linked to involvement of the mediastinal serous cavity 下载免费PDF全文
Karine Gendron Sean P. McDonough James A. Flanders May Tse Peter V. Scrivani 《Veterinary radiology & ultrasound》2018,59(2):169-179
The mediastinal serous cavity is a normal anatomic space in the caudal mediastinum. Aims of this anatomic and case series study were to describe the signs of pathologic expansion of the mediastinal serous cavity observed during computed tomography (CT), review the underlying anatomy, perform a literature review, and evaluate the medical records of several dogs with mediastinal serous cavity empyema (paraesophageal empyema). The mesothelial lined mediastinal serous cavity is a cranial extension of the omental bursa, separated from the peritoneal cavity by the diaphragm, in the dorsal part of the caudal mediastinum, to the right of the esophagus, between the heart base and diaphragm. In five adult, large‐breed dogs with surgically and histologically confirmed paraesophageal empyema, macroscopic plant material was found at surgery in two dogs, adherence to adjacent lung was present in three different dogs, accessory lobectomy was performed in two dogs with subacute‐chronic pyogranulomatous pneumonia, and one dog had concurrent pyothorax and mediastinitis, but none had esophageal abnormalities. This study expands our understanding of the pathogenesis and basis for the imaging appearance of paraesophageal empyema in dogs by clarifying the underlying anatomic structures that direct development of this condition. The term empyema accurately describes this condition because the purulent material accumulates within an existing body cavity. The study also provides initial evidence that the development of paraesophageal empyema might be due to local extension of lung disease, such as foreign body migration or pneumonia. Computed tomography was helpful for diagnosis, assessing size, and determining the spread of disease. 相似文献
97.
Benoît Pisanu Karine Laroucau Rachid Aaziz Fabien Vorimore Ariane Le Gros Jean-Louis Chapuis Philippe Clergeau 《Journal of Exotic Pet Medicine》2018,27(2):68-74
The crossing of host species barriers, through the spreading populations of introduced pet animals that become established in the wild, sets the stage for zoonotic pathogen (re)emergence. A literature review on pathogens that are hosted by the ring-necked parakeet (Psittacula krameri), a worldwide introduced pet, highlighted local infections of captive birds by chlamydial agents with high sanitary risk for human health in its introduced range. We searched for these pathogens through cloacal swabs collected from 85 individuals in an invasive population established in the suburban areas of Paris (Ile-de-France) from 5 localities during the winter seasons between 2011 and 2014. Based on quantitative PCR analysis, Chlamydiaceae shedding was detected at too low levels for species identification in 5 birds, but 1 parakeet (found dead) was positive for Chlamydiaceae typed as Chlamydia avium. The only known hosts recorded for C. avium in Europe are feral pigeons (Columba livia) and captive psittacines. This result raises the question of the sanitary risks associated with new pathogen transmission from exotic pets released in the wild, which could locally affect birds and potentially people who feed birds. 相似文献
98.
99.
Ludwig Spannhof Dimeter Nasev Hanne-Lore Kreutzmann 《Aquaculture (Amsterdam, Netherlands)》1979,18(4):317-323
A method is proposed for detecting metabolic disturbances or diseases in trout stocks before typical symptoms appear. The method involves determination of erythrocyte numbers, hemoglobin contents, and hematocrit readings for about 10 animals. The measured parameters are tested for independence. The results permit the stocks tested to be classified as “normal” or “not normal”. 相似文献
100.
Julia Antongiovanni Joselevitch Thiago Henrique Moroni Vargas Lidia Hildebrand Pulz Karine Germano Cadrobbi Greice Cestari Huete Adriana Tomoko Nishiya Silvia Regina Kleeb José Guilherme Xavier Ricardo De Francisco Strefezzi 《Veterinary and comparative oncology》2023,21(3):401-405
Mast cell tumour (MCT) is one of the most frequent skin tumours in dogs. Due to their unpredictable biological behaviour, MCTs often cause several therapeutic frustrations, leading to investigation regarding prognostic markers. Lysyl oxidase (LOX) is an enzyme that promotes extracellular matrix stability and contributes to cell migration, angiogenesis and epithelial-mesenchymal transition. Its expression positively correlates with poor prognoses in several human and canine mammary cancers. The aim of this study was to characterise the immunohistochemical expression of LOX in MCT samples and compare it with histological grading and post-surgical survival. Twenty-six tumours were submitted to immunohistochemistry for LOX expression evaluation. All samples were positive for LOX, with variable percentages of cytoplasmic and nuclear positivity. Cytoplasmic positivity was significantly higher in high-grade MCTs (P = .0297). Our results indicate that high expression of cytoplasmic LOX in neoplastic mast cells is an indicator of poor prognosis for canine cutaneous MCTs. 相似文献