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331.
Stephan Kaiser DVM MS Daniel Cornely MD Werner Colder MD PhD Michael T. Garner BA CVM K.-J. Wolf MD PhD Helmut Waibl DVM PhD Leo Brunnberg DVM PhD 《Veterinary radiology & ultrasound》2001,42(2):113-118
Measurements from magnetic resonance (MR) images can be used to examine the anteversion angle (AT-angle) and its influence on the lateromedial or mediolateral luxating forces on the patella. The AT-angle of the femoral neck was measured with the aid of MR imaging in 45 pelvic limbs without patellar instability, in 33 limbs with patellar luxation and in 6 limbs with rupture of the cranial cruciate ligament. The limbs with medial patellar luxation were divided into three groups based on clinical examination. The mean (range) AT-angle was 7.6 degrees (0 degrees to 24 degrees) in the "normal" group, 8.6 degrees (-10 degrees to 29 degrees) in the group "grade II," and -0.4 degrees in the group "grade III" (-28 degrees to 12 degrees). A mean (range) AT-angle of 4.8 (-4 degrees to 11 degrees) was measured in the pelvic limbs with rupture of the cranial cruciate ligament. Compared to literature that described AT-angles based on radiographs of normal limbs, reduced AT-angles were found in this study due to different lines of measurement of the femoral neck. This study documents that the AT-angle of the femoral neck does not influence patellar instability. This study also demonstrates that MR images can be used to make exact measurements of the canine AT-angle that represent the true anatomy of the femoral neck. 相似文献
332.
333.
Background
Recent studies of anadromous salmon (Oncorhynchus spp.) on the Pacific Coast of North America indicate an important and previously unrecognized role of salmonid nutrients to terrestrial biota. However, the extent of this uptake by primary producers and consumers and the influences on community structure remain poorly described. We examine here the contribution of salmon nutrients to multiple taxa of riparian vegetation (Blechnum spicant, Menziesii ferruginea, Oplopanax horridus, Rubus spectabilis, Vaccinium alaskaense, V. parvifolium, Tsuga heterophylla) and measure foliar δ15N, total %N and plant community structure at two geographically separated watersheds in coastal British Columbia. To reduce potentially confounding effects of precipitation, substrate and other abiotic variables, we made comparisons across a sharp ecological boundary of salmon density that resulted from a waterfall barrier to salmon migration.Results
δ15N and %N in foliage, and %cover of soil nitrogen indicators differed across the waterfall barrier to salmon at each watershed. δ15N values were enriched by 1.4‰ to 9.0‰ below the falls depending on species and watershed, providing a relative contribution of marine-derived nitrogen (MDN) to vegetation of 10% to 60%. %N in foliar tissues was slightly higher below the falls, with the majority of variance occurring between vegetation species. Community structure also differed with higher incidence of nitrogen-rich soil indicator species below the waterfalls.Conclusions
Measures of δ15N, %N and vegetation cover indicate a consistent difference in the riparian community across a sharp ecological boundary of salmon density. The additional N source that salmon provide to nitrogen-limited habitats appears to have significant impacts on the N budget of riparian vegetation, which may increase primary productivity, and result in community shifts between sites with and without salmon access. This, in turn, may have cascading ecosystem effects in forests adjacent to salmon streams.334.
Bone mineral content of the third metacarpal bone in Quarter Horse foals from birth to one year of age 总被引:1,自引:0,他引:1
Peter Reichmann MD Alessandro Moure MSc Humberto Remigio Gamba MD 《Journal of Equine Veterinary Science》2004,24(9):391-396
Dual photon absorptiometry (DPA) is a valid method for bone mineral content (BMC) evaluation, but there are no reports on the use of this technology in in vivo studies in the horse. The aim of the current study was to evaluate the changes of BMC of the third metacarpal bone (MC3) in vivo in foals during their first year of life using DPA. The BMC of the MC3 of 41 Quarter Horse foals was evaluated every 4 weeks during their first year of life by DPA using a bienergetic Gadolinium-153 (153Gd) source. To the authors' knowledge, this is the first report of an in vivo study of BMC in foals using DPA by means of a bienergetic 153Gd source. The results demonstrated a positive correlation of age, heart girth, and withers height with BMC of the MC3 independent of gender and an exponential behavior of the BMC increment along the first year of life. There was an effect of weaning associated with change in diet and stall confinement on BMC in foals weaned at age 17 weeks, but not in foals weaned at age between 19 and 24 weeks. 相似文献
335.
Rodrigo B Nogueira DVM MS Michiko Sakate DVM MS PhD Beatriz B Matsubara MD MS PhD Renato de Souza Gonalves MD Guilherme J Magalhes Rosa BS MS PhD 《Journal of Veterinary Cardiology》2003,5(2):29-32
The objective of this study was to evaluate the electrocardiographic alterations in the cardiac rhythm in dogs treated with levamisole hydrochloride over a period of 24 hours. Thirty-six mixed-breed dogs, both male and female, all clinically healthy, were used in the experiment. The dogs were divided into 6 groups with 6 dogs in each group, according to dosage and route of administration. The Holter test was initiated immediately after the treatment, and was maintained for 24 hours. In the group treated with 10 mg/kg by way of subcutaneous injection, one of them showed ventricular premature complexes, sometimes isolated and other times in pairs, and ventricular tachycardia, concentrated mainly in the first hour after administration of the drug. In the group of 6 animals treated subcutaneously with 25mg/kg, four showed isolated ventricular premature complexes, ventricular bigeminy and trigeminy, mainly during the first 2 hours after administration of the drug. All the animals in the other groups showed sinus arrhythmia followed by sinus arrest. The disturbances in the cardiac rhythm observed in clinically healthy animals treated with levamisole hydrochloride, indicate that it is preferable to avoid subcutaneous administration of levamisole hydrochloride and that the oral administration of the drug should be done with caution. 相似文献
336.
María F Martín PD PhD María S Carrasco MD PhD Jesús Usón-Gargallo DVM PhD Juan R Lima DVM Luis J Ezquerra DVM PhD 《Veterinary anaesthesia and analgesia》2001,28(3):132-139
Objective To compare the magnitude and duration of the peri‐operative haematological, endocrine and metabolic effects of surgery performed under sevoflurane anaesthesia. Study Design Prospective randomized study. Animals Ten, 55‐day‐old lambs of both sexes, mean weight 20.8 ± 0.3 kg (range 18.5–23.6 kg). Methods Animals were randomly allocated to two equal groups. All were anaesthetized with sevoflurane for 3 hours. Surgery (end‐to‐end anastomosis of the right carotid artery and right jugular vein) was performed in animals of Group 1 only. The electrocardiogram, pulse oximetry, cardiac output and noninvasive arterial blood pressure (NIBP) were monitored. Venous blood samples (5 mL) were taken 30 minutes before induction of anaesthesia (T = 0) and 1 (T1), 24 (T2), 48 hours (T3) and 7 days (T4) after anaesthesia in order to measure plasma cortisol, ACTH, insulin, cyclic adenosine monophosphate (cAMP), glucose, protein concentrations and haematological variables. Results Sevoflurane decreased NIBP (minimum mean value: 64 ± 3 mm Hg) in both groups. Plasma cortisol and ACTH concentration increased in Group 1 (maximum mean values: cortisol: 136.2 nmol L?1, ACTH: 54.5 pmol L?1) and Group 2 (maximum mean values: cortisol: 128.7 nmol L?1, ACTH: 44.0 pmol L?1). Cyclic AMP increased only in Group 1 (9.3 nmol) 1 hour after anaesthesia. Neutrophilia, lymphopaenia and a decreased PCV were observed in both groups 1 hour after anaesthesia. Plasma protein and glucose concentrations did not change. Conclusions Increased ACTH and cortisol concentrations recorded 1 hour after anaesthesia suggest that sevoflurane induces a stress response in lambs. Clinical relevance The study did not identify the mechanism by which sevoflurane induces a stress response although hypotension is implicated. 相似文献
337.
Summary Fifty lines of oats (Avena Sativa L.) with a broad range of nitrogen harvest indexes (NHI) and nine check lines were evaluated in 15 environments to study the association between NHI and adaptability of oat lines to soils with different productivity levels due primarily to different amounts of N. Three yield characteristics (i.e., mean across environments, regression response to improving environments, and stability of response) were used to measure adaptability. The lines were significantly variable for means of grain and straw yield, for responsiveness to improving environments, and for stability of yield. Among the yield characteristics, only the mean of grain yield was significantly correlated with NHI.Journal Paper No. J-13336 of the Iowa Agric. and Home Econ. Exp. Stn., Ames, Iowa, 50011. Project 2447. 相似文献