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排序方式: 共有333条查询结果,搜索用时 46 毫秒
71.
Manuel Pequito Hélène Amory Didier Serteyn Valeria Busoni Brieuc de Moffarts Charlotte Sandersen 《Journal of Equine Veterinary Science》2012
The objective of this study was to compare the sedative and peripheral hemodynamic effects of acepromazine (ACP) and promethazine (PTZ) in the standing healthy horse. Nine healthy Warmblood horses randomly received either intravenous ACP at 0.1 mg/kg or PTZ at 0.1, 0.2, and 0.3 mg/kg. A sedation score based on clinical examination was recorded, and systolic arterial blood pressure was noninvasively evaluated using a Doppler flow detector at the tail, just before and every 15 minutes until 60 minutes after drug injection. Hemodynamics of the median artery of the left forelimb was studied using Doppler ultrasonography just before and 45 minutes after injection of the drug, which allowed calculation of surface (SURF), diameter (DIAM), and circumference (CIRC) of the vessel and peak systolic velocity (PSV), end diastolic velocity (EDV), mean velocity (MV), volumetric flow (VF), and resistivity index (RI) of the blood flow. Regardless of the dose used, PTZ had lesser sedative and hypotensive effects than ACP at 0.1 mg/kg and did not induce significant variations in SURF, DIAM, CIRC, PSV, EDV, MV, VF, and RI of the studied standing horses. Conversely, the vasodilatory properties of ACP were illustrated by a significant increase in SURF, DIAM, CIRC, PSV, EDV, MV, and VF and a significant reduction of the RI. Unlike ACP, PTZ did not induce alterations on the morphology of the Doppler waveform. PTZ appears to have less sedative and peripheral vasodilator effects than ACP, thus it could be safer than ACP in patients suffering from hypotension. 相似文献
72.
Myeloperoxidase in Equine Semen: Concentration and Localization during Freezing Processing 总被引:1,自引:0,他引:1
Jérôme Ponthier Maud DesvalsThierry Franck PhD Geoffroy de la Rebière Marc SpalartEric Palmer Didier Serteyn Stéfan Deleuze 《Journal of Equine Veterinary Science》2012,32(1):32-37
Myeloperoxidase (MPO) is a pro-oxidant enzyme contained in and released by neutrophils during degranulation or after lysis. Post-thaw semen contains MPO, and concentration of this enzyme is associated with decreased motility. The aim of this study was to determine kinetics of MPO concentration during freezing, its origin, and its impact on frozen-thawed semen. Forty ejaculates were used. Semen was frozen using the classical freezing procedure. MPO concentrations were assayed in fresh semen, after centrifugation, and after cooling down to 4°C. Post-thaw MPO assay results and spermogram characteristics were determined. MPO immunocytochemistry was performed on 4 different ejaculates at each step of freezing procedure. MPO concentration increased after cooling down to 4°C and thawing compared with fresh semen. As temperature decreased, MPO was higher or tended to be higher in post-thaw poor quality samples. Nonsperm cells showed various degrees of MPO immunostaining and were observed as epithelial cells with nuclear pyknosis and keratinization. MPO immunostaining increased in medium and decreased in nonsperm cells during freezing. Our study shows that MPO concentration in equine semen increases when temperature decreases. We hypothesize that nonsperm cells present in fresh semen could release MPO. 相似文献
73.
74.
Meyer G Deplanche M Roux D Moulignie M Picard-Hagen N Lyazrhi F Raboisson D Mathevet P Schelcher F 《Veterinary journal (London, England : 1997)》2012,192(2):242-245
A modified-live vaccine has been shown previously to prevent fetal infection with bovine viral diarrhoea virus (BVDV)-2 and, to some extent BVDV-1, when used in association with an inactivated vaccine in a two-step vaccination protocol. In this challenge study, the modified-live vaccine used alone was able to protect 13 heifers between 49 and 96 days of gestation at challenge from leucopenia and virus replication and, for a 4-month period, to prevent fetal infection. The efficacy of the BVDV-1f 22146/Han81 challenge was demonstrated by virus isolation from the fetuses of all nine non-vaccinated, control heifers. However, the small number of heifers tested meant that the vaccination failure rate could be as high as 10% in the field. 相似文献
75.
Roy C Roque JL François PM Ferrieres A Raboisson D 《Veterinary journal (London, England : 1997)》2012,193(1):274-276
Udder-thigh dermatitis (UTD) is a common disease in dairy cattle. The aim of this study was to define UTD incidence, its risk factors and the involved pathogens. Of 74 respondents, 72 (97%) reported having had the disease. On those farms the incidence was 5.3 cases per 100 cow years. The odds ratio (OR) of UTD in primiparous compared to multiparous cows was 23.4 (95% CI 17.3-33.8). Compared to tied stalls, the ORs of UTD were 0.65 (95% CI 0.45-0.92) and 0.43 (95% CI 0.24-0.71) for free stalls and straw yards, respectively. Udder oedema was reported in 98.3% of cows with UTD. The most common bacteria isolated from affected skin were Fusobacterium spp. (12/14 cases). This study suggests that UTD management should focus on local treatment, reducing udder oedema and increasing exercise. 相似文献
76.
Spotted fever group Rickettsiae are predominantly transmitted by ticks. Rickettsiae have developed many strategies to adapt to different environmental conditions, including those within their arthropod vectors and vertebrate hosts. The tick-Rickettsiae relationship has been a point of interest for many researchers, with most studies concentrating on the role of ticks as vectors. Unfortunately, less attention has been directed towards the relationship of Rickettsiae with tick cells, tissues, and organs. This review summarizes our current understanding of the mechanisms involved in the relationship between ticks and Rickettsiae and provides an update on the recent methodological improvements that have allowed for comprehensive studies at the molecular level. 相似文献
77.
Pascal Jouquet Thierry Henry-des-Tureaux Jérôme Mathieu Thuy Doan Thu Toan Tran Duc Didier Orange 《CATENA》2010
This work focuses on a new approach to quantify the effects of above-ground earthworm's activity on soil erosion in steep slope ecosystems such as in Northern Vietnam. In these areas and in many others in the world, soil erosion becomes a major issue while the factors that determine it are still misunderstood. Earthworm's activity is believed to influence soil erosion rate, but we are still unable to precisely quantify their contribution to soil erosion. In this study, we used Near Infrared Reflectance Spectroscopy (NIRS) to quantify the proportion of soil aggregate in eroded soil coming from earthworm activity. This was done by generating NIRS signatures corresponding to different soil surface aggregates (above-ground soil casts produced by earthworms vs. surrounding topsoil). 相似文献
78.
Etienne Cossart Monique Fort Didier Bourles Julien Carcaillet Romain Perrier Lionel Siame Régis Braucher 《CATENA》2010
Recent advances in geochronology provide opportunities to identify the glacial and periglacial sequences in mountain area. In this paper, we focus on the Upper Durance catchment (Southern French Alps), in the Clarée valley, where no absolute chronological benchmark was defined. Glacial remnants and periglacial features were investigated, integrated within a chronological scenario thanks to relative (weathering rind thickness) and absolute (CRE technique) dates. We find evidence of the existence of a Late-Glacial valley glacier, that has never been reported before. Then the upper valleys became ice-free during a period corresponding to the Early-Holocene Climate Optimum, whereas two sequences of cirque glaciation are identified during the second half of the Holocene. We also show evidence of three main generations of rockglaciers, which also mainly developed during the second half of the Holocene, probably at the end of the Subboreal period. The location and the altitudes of rockglaciers are strongly dependent on the geomorphic setting (especially the location of the sediment sources), hence complicating their palaeo-climatic interpretations. 相似文献
79.
Benlasher E Geng X Nguyen NT Tardieu D Bailly JD Auvergne A Guerre P 《Avian diseases》2012,56(1):120-127
Fumonisins (FBs) are mycotoxins that are found worldwide in maize and maize products. Their main toxic effects have been well characterized in poultry, but differences between species have been demonstrated. Ducks appeared very sensitive to toxicity, whereas turkeys are more resistant. At the same time, alterations of sphingolipid metabolism, with an increase of the concentration of the free sphinganine (Sa) in serum and liver, have been demonstrated in the two species, but the link between the toxicity of FBs and Sa accumulation remains difficult to interpret. The aim of the present work was to compare the effects of FBs (10 mg FB1 + FB2/kg body weight) on sphingolipid metabolism in ducks and turkeys. Growth, feed consumption, and serum biochemistry were also investigated to evaluate toxicity. The main results showed that FBs increased Sa concentrations in liver and serum in ducks and turkeys, but these accumulations were not directly correlated with toxicity. Sa accumulation was higher in the livers of turkeys than in ducks, whereas Sa levels were higher in the sera of ducks than in turkeys. Hepatic toxicity was more pronounced in ducks than in turkeys and accompanied a decrease of body weight and an increase of serum biochemistry in ducks but not in turkeys. So, although FBs increase Sa concentration in the livers of both species, this effect is not directly proportional to toxicity. The mechanisms of FB toxicity and/or the mechanisms of protection of ducks and turkeys to the Sa accumulation within the liver remain to be established. 相似文献
80.
Chetboul V Sampedrano CC Concordet D Tissier R Lamour T Ginesta J Gouni V Nicolle AP Pouchelon JL Lefebvre HP 《American journal of veterinary research》2005,66(6):953-961
OBJECTIVE: To determine left ventricular free wall (LVFW) radial and longitudinal myocardial contraction velocities in healthy dogs via quantitative 2-dimensional color tissue Doppler imaging (TDI). ANIMALS: 100 dogs. PROCEDURE: TDI was used by a single trained observer to measure radial and longitudinal myocardial movement in the LVFW. Radial myocardial velocities were recorded in segments in the endocardial and epicardial layers of the LVFW, and longitudinal velocities were recorded in segments at 3 levels (basal, middle, apical) of the LVFW. RESULTS: LVFW velocities were higher in the endocardial layers than in the epicardial layers. Left ventricular free wall velocities were higher in the basal segments than in the middle and apical segments. Radial myocardial velocity gradients, defined as the difference between endocardial and epicardial velocities, were (mean +/- SD) 2.5 +/- 0.8 cm/s, 3.8 +/- 1.5 cm/s, and 2.3 +/- 0.9 cm/s in systole, early diastole, and late diastole, respectively. Longitudinal myocardial velocity gradients, defined as the difference between basal and apical velocities, were 5.9 +/- 2.2 cm/s, 6.9 +/- 2.5 cm/s, and 4.9 +/- 1.7 cm/s in systole, early diastole, and late diastole, respectively. A breed effect was detected for several systolic and diastolic TDI variables. In all segments, systolic velocities were independent of fractional shortening. CONCLUSIONS AND CLINICAL RELEVANCE: LVFW myocardial velocities decreased from the endocardium to the epicardium and from base to apex, thus revealing intramyocardial radial and longitudinal velocity gradients. These indices could enhance conventional echocardiographic analysis of left ventricular function in dogs. Breed-specific reference intervals should be defined. 相似文献